fix(agent): synchronize SetSystemPrompt against concurrent rebuilds

- add promptMu to Agent guarding systemPrompt writes and the fantasy
  agent rebuild, fixing a data race when Kit.applyComposedSystemPrompt
  is invoked concurrently
- read systemPrompt under the same lock in GetSystemPrompt
- update the thread-safety stress test to use a non-nil agent so the
  SetSystemPrompt path is actually exercised under -race

.kit/extensions/go-edit-lint.go

@@ -1,268 +0,0 @@
-//go:build ignore
-
-package main
-
-import (
-	"context"
-	"encoding/json"
-	"fmt"
-	"os/exec"
-	"path/filepath"
-	"strings"
-	"time"
-
-	"kit/ext"
-)
-
-const (
-	diagnosticsTimeout = 20 * time.Second
-	maxOutputBytes     = 12_000
-)
-
-type toolPathInput struct {
-	Path string `json:"path"`
-}
-
-type lintResult struct {
-	Output string
-	Err    error
-}
-
-// Package-level state: set of .go files edited during the current agent turn.
-var editedFiles map[string]bool
-
-func Init(api ext.API) {
-	api.OnSessionStart(func(_ ext.SessionStartEvent, ctx ext.Context) {
-		ctx.Print("go-edit-lint extension loaded - will run gopls and golangci-lint after agent turns that edit Go files")
-	})
-
-	// Track edited .go files — don't lint yet.
-	api.OnToolResult(func(e ext.ToolResultEvent, ctx ext.Context) *ext.ToolResultResult {
-		if e.IsError || !isEditOrWrite(e.ToolName) {
-			return nil
-		}
-
-		absPath, ok := resolveGoFilePath(e.Input, ctx.CWD)
-		if !ok {
-			return nil
-		}
-
-		if editedFiles == nil {
-			editedFiles = make(map[string]bool)
-		}
-		editedFiles[absPath] = true
-		return nil
-	})
-
-	// After the agent turn ends, lint all collected files.
-	api.OnAgentEnd(func(e ext.AgentEndEvent, ctx ext.Context) {
-		if len(editedFiles) == 0 {
-			return
-		}
-
-		// Snapshot and reset immediately so the next turn starts clean.
-		files := editedFiles
-		editedFiles = nil
-
-		// Skip lint on errored turns.
-		if e.StopReason == "error" {
-			return
-		}
-
-		// Collect unique directories and file list for gopls.
-		var allGoplsOutput []string
-		for absPath := range files {
-			res := runGopls(ctx.CWD, absPath)
-			formatted := formatToolResult(res, "")
-			if formatted != "" {
-				allGoplsOutput = append(allGoplsOutput, fmt.Sprintf("# %s\n%s", filepath.Base(absPath), formatted))
-			}
-		}
-
-		lintRes := runGolangCILint(ctx.CWD, "./...")
-
-		goplsSection := "No diagnostics."
-		if len(allGoplsOutput) > 0 {
-			goplsSection = strings.Join(allGoplsOutput, "\n\n")
-		}
-		lintSection := formatToolResult(lintRes, "No lint issues.")
-
-		// Build file list for the report header.
-		var fileNames []string
-		for absPath := range files {
-			fileNames = append(fileNames, filepath.Base(absPath))
-		}
-
-		report := fmt.Sprintf(
-			"<go_diagnostics files=%q>\n[gopls]\n%s\n\n[golangci-lint]\n%s\n</go_diagnostics>",
-			strings.Join(fileNames, ", "),
-			goplsSection,
-			lintSection,
-		)
-
-		goplsIssues, lintIssues := countIssues(report)
-		hasIssues := goplsIssues > 0 || lintIssues > 0
-
-		if hasIssues {
-			// Show TUI block so the user sees it too.
-			var msgLines []string
-			msgLines = append(msgLines, fmt.Sprintf("Files: %s", strings.Join(fileNames, ", ")))
-			if goplsIssues > 0 {
-				msgLines = append(msgLines, fmt.Sprintf("gopls: %d issue(s)", goplsIssues))
-			}
-			if lintIssues > 0 {
-				msgLines = append(msgLines, fmt.Sprintf("golangci-lint: %d issue(s)", lintIssues))
-			}
-
-			borderColor := "#f9e2af" // yellow
-			if goplsIssues > 0 && lintIssues > 0 {
-				borderColor = "#f38ba8" // red
-			}
-
-			ctx.PrintBlock(ext.PrintBlockOpts{
-				Text:        strings.Join(msgLines, "\n"),
-				BorderColor: borderColor,
-				Subtitle:    "go-edit-lint",
-			})
-
-			// Inject a follow-up message so the agent fixes the issues.
-			ctx.SendMessage(report + "\n\n⚠️ DIAGNOSTICS FOUND: Please review and fix the issues above.")
-		} else {
-			ctx.PrintBlock(ext.PrintBlockOpts{
-				Text:        fmt.Sprintf("Files: %s\n✓ All clean", strings.Join(fileNames, ", ")),
-				BorderColor: "#a6e3a1",
-				Subtitle:    "go-edit-lint",
-			})
-		}
-	})
-}
-
-func isEditOrWrite(toolName string) bool {
-	return strings.EqualFold(toolName, "edit") || strings.EqualFold(toolName, "write")
-}
-
-func resolveGoFilePath(inputJSON, cwd string) (string, bool) {
-	var args toolPathInput
-	if err := json.Unmarshal([]byte(inputJSON), &args); err != nil || args.Path == "" {
-		return "", false
-	}
-
-	absPath := args.Path
-	if !filepath.IsAbs(absPath) {
-		absPath = filepath.Join(cwd, absPath)
-	}
-
-	if strings.ToLower(filepath.Ext(absPath)) != ".go" {
-		return "", false
-	}
-
-	return absPath, true
-}
-
-func runGopls(cwd, absPath string) lintResult {
-	ctx, cancel := context.WithTimeout(context.Background(), diagnosticsTimeout)
-	defer cancel()
-
-	cmd := exec.CommandContext(ctx, "gopls", "check", absPath)
-	cmd.Dir = cwd
-	out, err := cmd.CombinedOutput()
-
-	if ctx.Err() == context.DeadlineExceeded {
-		return lintResult{Err: fmt.Errorf("timed out after %s", diagnosticsTimeout)}
-	}
-
-	if err != nil {
-		return lintResult{Output: truncate(string(out), maxOutputBytes), Err: fmt.Errorf("failed to run gopls check: %w", err)}
-	}
-
-	return lintResult{Output: truncate(string(out), maxOutputBytes)}
-}
-
-func runGolangCILint(cwd, target string) lintResult {
-	ctx, cancel := context.WithTimeout(context.Background(), diagnosticsTimeout)
-	defer cancel()
-
-	args := []string{
-		"run",
-		target,
-		"--show-stats=false",
-		"--output.text.path", "stdout",
-		"--output.text.colors=false",
-		"--output.text.print-issued-lines=false",
-	}
-	cmd := exec.CommandContext(ctx, "golangci-lint", args...)
-	cmd.Dir = cwd
-	out, err := cmd.CombinedOutput()
-
-	if ctx.Err() == context.DeadlineExceeded {
-		return lintResult{Err: fmt.Errorf("timed out after %s", diagnosticsTimeout)}
-	}
-
-	trimmed := truncate(string(out), maxOutputBytes)
-	if err == nil {
-		return lintResult{Output: trimmed}
-	}
-
-	exitErr, ok := err.(*exec.ExitError)
-	if ok && exitErr.ExitCode() == 1 {
-		return lintResult{Output: trimmed}
-	}
-
-	return lintResult{Output: trimmed, Err: fmt.Errorf("failed to run golangci-lint: %w", err)}
-}
-
-func formatToolResult(res lintResult, emptyFallback string) string {
-	var lines []string
-	if res.Err != nil {
-		lines = append(lines, "ERROR: "+res.Err.Error())
-	}
-	out := strings.TrimSpace(res.Output)
-	if out == "" {
-		if res.Err == nil {
-			if emptyFallback != "" {
-				lines = append(lines, emptyFallback)
-			}
-		}
-	} else {
-		lines = append(lines, out)
-	}
-	if len(lines) == 0 {
-		return emptyFallback
-	}
-	return strings.Join(lines, "\n")
-}
-
-func truncate(s string, max int) string {
-	if len(s) <= max {
-		return s
-	}
-	return s[:max] + "\n... output truncated ..."
-}
-
-func countIssues(report string) (goplsCount, lintCount int) {
-	goplsStart := strings.Index(report, "[gopls]")
-	lintStart := strings.Index(report, "[golangci-lint]")
-	endTag := strings.Index(report, "</go_diagnostics>")
-
-	if goplsStart != -1 && lintStart != -1 {
-		goplsSection := report[goplsStart:lintStart]
-		for _, line := range strings.Split(goplsSection, "\n") {
-			line = strings.TrimSpace(line)
-			if line != "" && line != "[gopls]" && line != "No diagnostics." && !strings.HasPrefix(line, "#") {
-				goplsCount++
-			}
-		}
-	}
-
-	if lintStart != -1 && endTag != -1 {
-		lintSection := report[lintStart:endTag]
-		for _, line := range strings.Split(lintSection, "\n") {
-			line = strings.TrimSpace(line)
-			if line != "" && line != "[golangci-lint]" && line != "No lint issues." {
-				lintCount++
-			}
-		}
-	}
-
-	return goplsCount, lintCount
-}

.kit/prompts/code-audit.md

@@ -0,0 +1,146 @@
+---
+description: Read-only audit for dead code, duplication, boundary violations, and refactor opportunities
+---
+
+Perform a comprehensive **read-only** audit of this repository and report
+findings. **Do not edit, rename, or delete any files.** Optional focus / scope
+hints from the user: $@
+
+## Scope
+
+If the user supplied focus hints above (a package path, a subsystem name, a
+concern like "TUI" or "extensions"), scope the audit accordingly. Otherwise
+audit the whole repo, prioritising the highest-traffic packages first
+(`cmd/`, `internal/`, `pkg/kit/` for this repo).
+
+## Steps
+
+1. **Map the repo first**:
+   - `ls` / `find` the top-level layout and list every Go package
+   - Read `AGENTS.md`, `README.md`, and any `pkg/*/doc.go` to understand the
+     intended architectural boundaries (SDK vs internal vs TUI vs cmd vs
+     extension surface)
+   - Note the public SDK surface (`pkg/kit/`) and any documented invariants
+     (e.g. "no dependency name leakage", "UI never imports extensions
+     directly") — these define what counts as a violation
+
+2. **Hunt for dead code**:
+   - Run `go vet ./...` and capture warnings
+   - Use `grep` to find exported symbols (`^func [A-Z]`, `^type [A-Z]`,
+     `^var [A-Z]`, `^const [A-Z]`) and cross-reference call sites. Symbols
+     with zero non-test references inside the module are suspects
+   - Check for unreferenced files, `// TODO: remove` markers, commented-out
+     blocks, and `_ = x` discard patterns
+   - If `staticcheck`, `deadcode`, or `unused` are available on PATH, run
+     them and include their output verbatim
+   - **Do not delete anything** — list candidates with file:line and a
+     confidence level (high / medium / low)
+
+3. **Find unnecessary duplication**:
+   - Look for near-identical function bodies, struct shapes, or switch
+     statements across packages — `grep` for repeated function signatures
+     and copy-pasted string literals / error messages is a fast first pass
+   - Distinguish *coincidental* duplication (two things that happen to look
+     alike but evolve independently) from *unnecessary* duplication (same
+     intent, drifting in lockstep) — only flag the latter
+   - For each cluster, propose where the extracted helper should live
+     (which package, which file) and whether it crosses a boundary
+
+4. **Check concerns / boundary violations**:
+   - **SDK leakage**: grep `pkg/kit/` for imports of `internal/...` types
+     in exported signatures, and for dependency-name leakage in exported
+     names / godoc (e.g. library jargon appearing in `LLM*` types)
+   - **UI ↔ extensions**: grep `internal/ui/` for any import of
+     `internal/extensions/` — per AGENTS.md the UI must not import
+     extensions directly; converters in `cmd/root.go` should bridge them
+   - **cmd vs internal**: business logic living in `cmd/` that should be
+     in `internal/` (and vice versa)
+   - **Cyclic risk**: packages that import each other transitively or that
+     reach across sibling boundaries unexpectedly
+   - For each violation, cite the offending import / signature with
+     file:line
+
+5. **Spot refactor opportunities**:
+   - Long functions (>80 lines) doing multiple unrelated things
+   - Deeply nested conditionals that flatten well with early returns
+   - Repeated `if err != nil { return fmt.Errorf("...: %w", err) }` chains
+     that could become helpers — but only where the wrapping context is
+     genuinely uniform
+   - Structs with too many fields that hint at split responsibilities
+   - Exported APIs that would be cleaner with options structs / functional
+     options
+   - Tests that share setup boilerplate ripe for a helper
+   - Flag each with: location, current shape (1-2 lines), proposed shape
+     (1-2 lines), and estimated risk (low / medium / high)
+
+6. **Cross-check against project rules**:
+   - Re-read `AGENTS.md` "Key Patterns" section and verify nothing in your
+     findings contradicts the documented gotchas (Yaegi interface ban,
+     `prog.Send()` from `Update()`, function-field bug, etc.) — if a
+     "refactor" would reintroduce a known pitfall, drop it from the report
+     and note why
+
+7. **Write the report** as your final message (do not write it to disk)
+   structured as:
+
+   ```
+   # Code Audit Report
+
+   ## Summary
+   - N dead-code candidates
+   - N duplication clusters
+   - N boundary violations
+   - N refactor opportunities
+
+   ## Dead Code
+   ### High confidence
+   - path/to/file.go:LINE — symbol — reason
+
+   ### Medium confidence
+   ...
+
+   ## Duplication
+   ### Cluster: <short name>
+   - Sites: file:line, file:line, …
+   - Suggested home: package/path
+   - Notes: …
+
+   ## Boundary Violations
+   - Rule: <which rule from AGENTS.md / project convention>
+   - Offender: file:line
+   - Fix sketch: …
+
+   ## Refactor Opportunities
+   - Location: file:line
+   - Current: …
+   - Proposed: …
+   - Risk: low/medium/high
+   - Why it's worth it: …
+
+   ## Suggested Next Steps
+   1. …
+   2. …
+   ```
+
+8. **End the report with an explicit reminder** that no files were modified,
+   and recommend the user pick the highest-leverage items to act on
+   manually (or via a follow-up `/fix-issue` style prompt) rather than
+   running a sweeping refactor.
+
+## Guidelines
+
+- **Read-only, always**: no `edit`, no `write`, no `git commit`, no `go mod
+  tidy`. Use only `read`, `grep`, `find`, `ls`, and read-only `bash`
+  commands (`go vet`, `go build -o /tmp/...`, `staticcheck`, etc.)
+- **Cite every finding** with `path/to/file.go:LINE` so the user can jump
+  straight to it
+- **Be honest about confidence**: false positives in a code audit are
+  expensive — prefer "medium confidence, worth a look" over confidently
+  wrong claims
+- **Quantity isn't quality**: 10 sharp findings beat 100 nitpicks. Cut
+  anything that's purely stylistic unless it directly causes one of the
+  four issue categories above
+- **Skip generated code** (`*.pb.go`, `*_gen.go`, anything under
+  `vendor/`) and obvious third-party copies
+- **Don't propose architectural rewrites** — stay within the existing
+  shape of the repo and recommend incremental, reviewable changes

.kit/prompts/create-pr.md

@@ -0,0 +1,47 @@
+---
+description: Open a GitHub PR for the current branch using the repo's PR template
+---
+
+Open a GitHub pull request for the current branch, filling out the repository's PR template with a description grounded in the actual commits and diff.
+
+## Steps
+
+1. **Verify the branch is pushed**:
+   - `git status -sb` and `git log @{u}..HEAD --oneline 2>/dev/null` — if there is no upstream or unpushed commits, run `git push -u origin "$(git branch --show-current)"` first
+   - If the working tree is dirty, stop and tell the user to commit first (suggest `/commit-push`)
+2. **Gather context**:
+   - `git log origin/main..HEAD --oneline` — list of commits going into the PR
+   - `git diff origin/main...HEAD --stat` then `git diff origin/main...HEAD` — read the actual changes
+   - Identify the linked issue (from commit messages, branch name, or extra user input: $@) — capture as `Fixes #N` if applicable
+3. **Locate the PR template**:
+   - Check `.github/pull_request_template.md`, `.github/PULL_REQUEST_TEMPLATE.md`, or `docs/pull_request_template.md`
+   - If none exists, use a minimal `## Description` / `## Type of Change` / `## Checklist` structure
+4. **Draft the PR body** by filling out the template:
+   - **Description**: 1–3 short paragraphs explaining *what* changed and *why*, grounded in the diff. Include a brief before/after example for new APIs when useful.
+   - **Fixes #N**: only if there is a real linked issue
+   - **Type of Change**: tick the single most accurate box with `[x]` (leave others as `[ ]`)
+   - **Checklist**: tick items that are genuinely true (style, self-review, tests added, docs updated)
+   - **Additional Information**: bullet list of added / modified files and any backward-compatibility notes
+   - Remove template sections explicitly marked "remove if not applicable" (e.g. MCP Spec Compliance) when they don't apply
+5. **Write the body to a temp file**: `/tmp/pr-body-<branch-or-issue>.md` — never inline a long body via `--body`, always use `--body-file`
+6. **Choose the title**: prefer the subject of the primary commit if it already follows Conventional Commits; otherwise craft one in the same style (`<type>(<scope>): <imperative summary>`, ≤72 chars)
+7. **Create the PR**:
+   ```
+   gh pr create \
+     --title "<title>" \
+     --body-file /tmp/pr-body-<...>.md \
+     --base main \
+     --head "$(git branch --show-current)"
+   ```
+   Use the repo's actual default branch if it isn't `main` (`gh repo view --json defaultBranchRef -q .defaultBranchRef.name`)
+8. **Report the PR URL** returned by `gh` and stop
+
+## Guidelines
+
+- Read the diff and commit messages — do **not** invent features that aren't in the code
+- One PR per logical change; if the branch contains unrelated commits, surface that and ask before continuing
+- Keep the description focused on reviewer-relevant information (what / why), not a replay of the diff
+- Only check checklist boxes that are actually satisfied; leave the rest unchecked rather than lying
+- If `gh` is not authenticated (`gh auth status` fails), stop and tell the user
+
+$@

.kit/prompts/feature-request.md

@@ -2,7 +2,7 @@
 description: Create a feature request using the GitHub template
 ---
 
-Create a feature request for the Kit repository. The user wants to request: $+
+Create a feature request for the Kit repository. The user wants to request: $@
 
 ## Feature Request Template
 
@@ -16,7 +16,7 @@ This prompt uses the `feature_request` GitHub template which requires:
 
 ## Steps
 
-1. **Understand the request** from `$+`
+1. **Understand the request** from the user input: $@
    - What capability is missing?
    - What would the ideal behavior look like?
 

.kit/prompts/file-issue.md

@@ -2,7 +2,7 @@
 description: File a GitHub issue using the appropriate template
 ---
 
-File a GitHub issue for the Kit repository. The user wants to create an issue about: $+
+File a GitHub issue for the Kit repository. The user wants to create an issue about: $@
 
 ## Issue Templates Available
 
@@ -16,7 +16,7 @@ This repository has structured issue templates. You MUST use the appropriate tem
 
 ## Steps
 
-1. **Determine the issue type** from `$+`:
+1. **Determine the issue type** from the user input: $@
    - Bug → use `--template bug_report`
    - Feature → use `--template feature_request`  
    - Documentation → use `--template documentation`

.kit/prompts/fix-issue.md

@@ -0,0 +1,61 @@
+---
+description: Implement the fix/feature/docs change requested by a GitHub issue
+---
+
+Resolve GitHub issue #$1 by reading it, classifying it, and producing the appropriate code or doc change. **Stop once the working tree contains the change** — committing, pushing, and opening a PR are handled by `/commit-push` and `/create-pr`.
+
+## Steps
+
+1. **Fetch the issue**:
+   - Run: gh issue view $1 --json number,title,body,labels,state,author,comments
+   - If the issue is closed, stop and ask the user whether to proceed
+   - Read the **entire** thread including comments — the latest comment often refines the ask
+
+2. **Classify the issue** from labels, title prefix, and body content:
+   - `bug` / `fix:` → reproduce, then fix
+   - `enhancement` / `feature` / `feat:` → design, then implement
+   - `documentation` / `docs:` → locate and update docs
+   - `question` / `discussion` → answer in a comment, do **not** write code
+   - Anything else → ask the user how to proceed
+
+3. **Create a working branch** off the default branch:
+   - `git checkout main && git pull --ff-only`
+   - Branch name: <type>/$1-<slug> (e.g. `fix/42-borderColor-ignored`, `feat/57-keyboard-clear`, `docs/63-widget-lifecycle`)
+
+4. **Do the work** based on type:
+
+   ### Bug (`bug` label / `fix:` title)
+   - Reproduce the failure first (write a failing test if feasible) — if you cannot reproduce, comment on the issue asking for clarification and stop
+   - Locate the root cause; do not patch symptoms
+   - Add or extend a regression test that fails before and passes after the fix
+   - Run `go test ./... -race` and `golangci-lint run`
+
+   ### Feature (`enhancement` / `feature` label / `feat:` title)
+   - Re-read the motivation and proposed implementation in the issue body
+   - For large, ambiguous, or breaking changes, sketch the design in a comment on the issue and wait for sign-off before writing code
+   - Implement behind sensible defaults; add godoc on every exported symbol
+   - Add unit tests covering the new behaviour and edge cases
+   - Update `README.md` / `docs/` if the public surface changed
+   - Run `go test ./... -race` and `golangci-lint run`
+
+   ### Documentation (`documentation` label / `docs:` title)
+   - Open the file/URL referenced in the issue's "Documentation Location"
+   - Apply the suggested improvement; verify code samples compile (`go build ./...`)
+   - No tests required, but run `golangci-lint run` if Go files were touched
+
+5. **Report**:
+   - Branch name (`git branch --show-current`)
+   - Summary of files changed (`git status -s`) and the diff highlights
+   - Test/lint results (pass/fail with key output)
+   - Suggest the next step explicitly:
+     - `/commit-push` to commit with a Conventional Commit subject (the message should reference `(#$1)` and include `Fixes #$1` so merge auto-closes)
+     - then `/create-pr $1` to open the pull request
+
+## Guidelines
+
+- This prompt **stops at a clean working tree with the change applied** — do not run `git commit`, `git push`, or `gh pr create`
+- If the issue is unclear, post a clarifying comment on the issue and stop; do not guess
+- Keep the change scoped to the issue; surface unrelated cleanups separately
+- For breaking changes or architecture shifts, propose the design on the issue first and wait for maintainer sign-off
+- If the issue is a duplicate or already fixed on `main`, comment with the reference and stop
+- Do not close the issue manually — the eventual PR's `Fixes #$1` handles that on merge

.kit/prompts/new-prompt.md

@@ -2,7 +2,7 @@
 description: Scaffold a new prompt template in .kit/prompts/
 ---
 
-Create a new kit prompt template. The user wants a prompt that does: $+
+Create a new kit prompt template. The user wants a prompt that does: $@
 
 ## What a prompt template is
 
@@ -16,30 +16,64 @@ It becomes a `/slug` slash command in the kit input box — typed as `/filename`
 description: One-line description shown in autocomplete
 ---
 
-Body text of the prompt. Use $@ for all user-supplied arguments,
-$1 $2 etc. for positional arguments.
+Body text of the prompt. Reference user-supplied arguments
+with positional placeholders (see "Argument placeholders" below).
 ```
 
 - **Filename** → slug: `commit-push.md` becomes `/commit-push`
 - **Frontmatter**: only `description` is recognised; keep it under ~80 chars
 - **Body**: plain markdown; the full text is submitted as the user's message when the template fires
-- **Arguments**: `$+` expands to everything the user typed after the slash command name
-  (requires at least one argument); `$@` is the same but allows zero arguments;
-  `$1`, `$2` for individual positional args; omit entirely if no arguments are needed
+- **Required args**: kit infers required positional args from the highest `$N` it finds *outside* backtick/tilde code fences — a stray `$2` in active prose means kit will refuse to run without 2 arguments
+
+## Argument placeholders
+
+kit performs shell-style substitution before sending the prompt to the model:
+
+- `$1`, `$2`, … — positional arguments (1-indexed)
+- `${1}`, `${2}`, … — same, brace form (use when followed by digits/letters: `${1}_suffix`)
+- `$@` — all arguments joined by spaces (zero or more, optional)
+- `$+` — all arguments, **at least one required**
+- `$ARGUMENTS` / `${ARGUMENTS}` — alias for `$@`
+- `${@:N}` — args from the Nth onwards (1-indexed, bash-style)
+- `${@:N:L}` — `L` args starting from the Nth
+
+### ⚠️ Critical: code fences and inline code preserve placeholders verbatim
+
+Anything inside triple-backtick fences, `~~~` fences, or single-backtick `inline` code spans is **left untouched** so example code samples don't get corrupted. That means:
+
+- An inline-coded `gh issue view $1` stays literal `$1` in the model's input ❌
+- The same command without backticks: gh issue view $1 → expands to `gh issue view 42` ✓
+
+**Rule of thumb:** if you want a placeholder to substitute, keep it outside backticks and fences. If you want a literal `$1` in the output (e.g. teaching the user shell syntax), put it inside backticks.
+
+### Workarounds for "I want it to look like code AND substitute"
+
+1. **Drop the backticks** around just the placeholder portion — the rest can still read as a command line in prose
+2. **Use a 4-space-indented code block** instead of a triple-backtick fence — kit only skips backtick/tilde fences, so indentation-style code blocks still get substitution:
+
+       git push -u origin "$(git branch --show-current)"
+       gh pr create --title "fix: ... (#$1)" --base main
+
+3. **Bind once, reference loosely**: put `Issue: $1` at the top in prose, then leave the backticked examples literal — the model will substitute mentally
 
 ## Steps
 
-1. **Understand the workflow** the user described in `$+` — ask a clarifying question if the intent is ambiguous
+1. **Understand the workflow** the user described in $@ — ask a clarifying question if the intent is ambiguous
 2. **Choose a filename**: short, lowercase, hyphen-separated, descriptive (e.g. `code-review.md`)
 3. **Write the description**: one sentence, imperative, fits in autocomplete
-4. **Draft the body**:
-   - Open with a single sentence stating the goal
+4. **Decide on arguments**:
+   - No args needed → omit placeholders entirely
+   - One required value (issue number, PR url, file path) → use `$1`
+   - Free-form trailing context → end with a single `$@` line
+   - Multiple distinct values → use `$1`, `$2`, … and document each at the top
+5. **Draft the body**:
+   - Open with a single sentence stating the goal, weaving in `$1`/`$@` where the value belongs
    - Use `## Steps` for multi-step workflows; use plain prose for simple prompts
    - Be specific: name commands, flags, and file paths where relevant
-   - End with `$+` on its own line if the user must pass context; use `$@` if arguments
-     are optional; omit if the prompt is self-contained
-5. **Write the file** to `.kit/prompts/<slug>.md`
-6. **Confirm** by showing the final file content and the slash command that activates it
+   - **Audit every backtick and code fence**: any `$N` or `$@` inside them will not expand — was that intentional? If not, apply one of the workarounds above
+6. **Write the file** to `.kit/prompts/<slug>.md`
+7. **Verify substitution** by mentally (or actually) replacing `$1`/`$@` with a sample value and confirming every reference resolves — and that the prompt's *own* example snippets don't accidentally bump the required-arg count (wrap illustrative `$N` examples in triple-backtick fences, not 4-space indentation, so `RequiredArgs()` ignores them)
+8. **Confirm** by showing the final file content and the slash command that activates it (e.g. `/code-review 42`)
 
 ## Guidelines
 
@@ -47,3 +81,4 @@ $1 $2 etc. for positional arguments.
 - Prefer concrete steps over vague instructions
 - A prompt that does one thing well beats one that tries to cover every edge case
 - If the workflow already exists as a prompt, suggest extending it instead of duplicating
+- When in doubt about substitution behaviour, write the file and run `/<slug> testvalue` once to confirm — wrong placement of backticks is the #1 failure mode

.kit/prompts/update-docs.md

@@ -0,0 +1,52 @@
+---
+description: Audit and update project documentation (README and docs site) for a recent change
+---
+
+Review recent code changes, identify all documentation surfaces that should
+mention them, and update each one — grounded in the actual diff, not guesses.
+
+## Steps
+
+1. **Identify the change**:
+   - If the user input ($@) names a commit / PR / branch / topic, use that as the focus
+   - Otherwise inspect `git log origin/main..HEAD --oneline` and `git diff origin/main...HEAD --stat` to discover what shipped on the current branch
+   - Read the actual diff (`git diff origin/main...HEAD`) — never document features that aren't in the code
+
+2. **Inventory the doc surfaces**:
+   - `README.md` at the repo root
+   - Any docs site (commonly `www/`, `docs/`, `site/`) — list its pages and identify the one(s) most thematically related to the change
+   - Inline godoc / API reference comments on the new exported symbols
+   - `CHANGELOG.md` if the project keeps one
+   - Any `examples/` directory entries that demonstrate the affected area
+
+3. **Audit each surface** with `grep`:
+   - Search for the names of related existing APIs (e.g. if you added `IterTools`, grep for `ListTools`) to find every page that already discusses the area
+   - Decide for each hit: does it need a cross-reference, a side-by-side comparison, or to stay untouched?
+
+4. **Decide where new content lives**:
+   - Prefer extending an existing page over creating a new one
+   - For a docs site, place new sections near related content (check the page's `## Heading` outline first)
+   - Skip surfaces that genuinely don't apply (e.g. a server-focused README for a client-only change) and say so explicitly
+
+5. **Draft the updates**:
+   - Lead with a one-sentence statement of what's new and why
+   - Show concrete code examples copied from real signatures — verify against the source files
+   - Include a comparison / "when to use which" table when adding an alternative to an existing API
+   - Note backwards-compatibility behaviour if relevant
+
+6. **Verify the docs build** before committing:
+   - For vocs / docusaurus / mkdocs sites, run the local build command (e.g. `npx vocs build`, `mkdocs build`) and fix any MDX/markdown errors
+   - For godoc, run `go vet ./...` and `go doc <pkg> <Symbol>` to sanity-check rendering
+
+7. **Report**:
+   - List every file changed and every file deliberately left alone (with a one-line reason)
+   - Suggest the next step (typically `/commit-push`) — do not auto-commit unless asked
+
+## Guidelines
+
+- Read the diff before writing anything — invented API names erode trust faster than missing docs
+- One change per doc commit; keep doc updates separate from code changes when possible
+- Match the existing voice and formatting of each surface (headings, code-fence languages, table styles)
+- Prefer linking between pages over duplicating content
+
+$@

README.md

@@ -162,6 +162,11 @@ mcpServers:
     type: remote
     url: "https://pubmed.mcp.example.com"
     noOAuth: true  # skip OAuth for public servers that don't require auth
+
+  builds:
+    type: remote
+    url: "https://builds.mcp.example.com"
+    tasksMode: always  # async task execution — see MCP Tasks below
 ```
 
 ## CLI Reference
@@ -626,6 +631,36 @@ in a custom `MCPTokenStoreFactory` for encrypted, DB-backed, or in-memory
 storage. See the [SDK options docs](/sdk/options#mcp-oauth-authorization) for
 the full matrix.
 
+### MCP Tasks (long-running tools)
+
+Kit advertises [MCP task support](https://modelcontextprotocol.io/specification/2025-11-25/basic/utilities/tasks)
+during `initialize`, so cooperating MCP servers can respond to `tools/call`
+with a `taskId` instead of blocking the connection. Kit then polls
+`tasks/get` / `tasks/result` until the task reaches a terminal state, and
+best-effort `tasks/cancel`s on context cancellation.
+
+Defaults are safe — a server that doesn't advertise task capability runs
+synchronously, exactly as before. Opt in per server via `tasksMode` in
+`.kit.yml` (`auto` | `never` | `always`) or programmatically through the SDK:
+
+```go
+host, _ := kit.New(ctx, &kit.Options{
+    MCPTaskMode: map[string]kit.MCPTaskMode{
+        "build-server": kit.MCPTaskModeAlways,
+    },
+    MCPTaskTimeout:  15 * time.Minute,
+    MCPTaskProgress: func(p kit.MCPTaskProgress) {
+        log.Printf("%s: %s", p.TaskID, p.Status)
+    },
+})
+
+tasks, _ := host.ListMCPTasks(ctx, "build-server")
+_, _    = host.CancelMCPTask(ctx, "build-server", tasks[0].TaskID)
+```
+
+See the [configuration docs](/configuration#mcp-tasks-long-running-tools) and
+[SDK options → MCP Tasks](/sdk/options#mcp-tasks) for the full surface.
+
 ### Custom Tools
 
 Create custom tools with automatic schema generation — no external dependencies needed:
@@ -721,6 +756,45 @@ host, _ := kit.New(ctx, &kit.Options{
 })
 ```
 
+### Runtime Skills & Context Files
+
+For multi-tenant hosts (chatbots, per-user agents, web services), the SDK
+lets you swap skills and `AGENTS.md`-style context files **after** Kit
+construction. Every mutation recomposes the system prompt and applies it to
+the agent so the next turn picks up the new instructions — no restart needed.
+
+```go
+// Programmatic skill (no file on disk required).
+host.AddSkill(&kit.Skill{
+    Name:        "polite-french",
+    Description: "Respond in French and always greet the user.",
+    Content:     "Always reply in French. Open every response with 'Bonjour'.",
+})
+
+// Or load one from disk.
+host.LoadAndAddSkill("/var/skills/refund-policy.md")
+
+// Per-user AGENTS.md content pulled from a database.
+host.AddContextFileContent(
+    fmt.Sprintf("session://%s/AGENTS.md", userID),
+    rulesFromDB,
+)
+
+// Tear down session-specific state on logout.
+host.RemoveSkill("polite-french")
+host.RemoveContextFile(fmt.Sprintf("session://%s/AGENTS.md", userID))
+
+// Or replace the whole set atomically.
+host.SetSkills(activeSkillsForUser)
+host.SetContextFiles(activeContextForUser)
+```
+
+Skills dedupe by `Name`, context files dedupe by `Path` (which can be any
+opaque identifier — it doesn't have to be a real filesystem path). All
+mutators and readers (`GetSkills`, `GetContextFiles`) are safe to call
+concurrently from multiple goroutines. See the [SDK overview docs](/sdk/overview#runtime-skills-and-context-files)
+for the full reference.
+
 ## Advanced Usage
 
 ### Subagent Pattern

cmd/extension_context.go

@@ -0,0 +1,473 @@
+package cmd
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/spf13/viper"
+	"golang.org/x/term"
+
+	"github.com/mark3labs/kit/internal/app"
+	"github.com/mark3labs/kit/internal/auth"
+	"github.com/mark3labs/kit/internal/extbridge"
+	"github.com/mark3labs/kit/internal/extensions"
+	"github.com/mark3labs/kit/internal/models"
+	"github.com/mark3labs/kit/internal/ui"
+	kit "github.com/mark3labs/kit/pkg/kit"
+)
+
+// extensionContextDeps groups the runtime dependencies needed to wire up
+// an extensions.Context for the interactive TUI mode.
+type extensionContextDeps struct {
+	ctx          context.Context
+	cwd          string
+	modelName    string
+	interactive  bool
+	kitInstance  *kit.Kit
+	appInstance  *app.App
+	usageTracker *ui.UsageTracker
+}
+
+// buildInteractiveExtensionContext returns an extensions.Context with every
+// field except Print / PrintInfo / PrintError populated. Callers must set
+// the three print routes appropriately for their phase (startup buffering
+// vs. live runtime routing).
+//
+// This consolidates two near-identical 400-line literal expressions that
+// previously appeared inline in runNormalMode.
+func buildInteractiveExtensionContext(deps extensionContextDeps) extensions.Context {
+	kitInstance := deps.kitInstance
+	appInstance := deps.appInstance
+	usageTracker := deps.usageTracker
+	ctx := deps.ctx
+
+	return extensions.Context{
+		CWD:         deps.cwd,
+		Model:       deps.modelName,
+		Interactive: deps.interactive,
+		PrintBlock: func(opts extensions.PrintBlockOpts) {
+			appInstance.PrintBlockFromExtension(opts)
+		},
+		SendMessage:   func(text string) { appInstance.Run(text) },
+		CancelAndSend: func(text string) { appInstance.InterruptAndSend(text) },
+		Abort:         func() { appInstance.Abort() },
+		IsIdle:        func() bool { return !appInstance.IsBusy() },
+		Compact: func(cfg extensions.CompactConfig) error {
+			return appInstance.CompactAsync(cfg.CustomInstructions, cfg.OnComplete, cfg.OnError)
+		},
+		SendMultimodalMessage: func(text string, files []extensions.FilePart) {
+			parts := make([]kit.LLMFilePart, len(files))
+			for i, f := range files {
+				parts[i] = kit.LLMFilePart{
+					Filename:  f.Filename,
+					Data:      f.Data,
+					MediaType: f.MediaType,
+				}
+			}
+			appInstance.RunWithFiles(text, parts)
+		},
+		GetSessionUsage: func() extensions.SessionUsage {
+			if usageTracker == nil {
+				return extensions.SessionUsage{}
+			}
+			stats := usageTracker.GetSessionStats()
+			return extensions.SessionUsage{
+				TotalInputTokens:      stats.TotalInputTokens,
+				TotalOutputTokens:     stats.TotalOutputTokens,
+				TotalCacheReadTokens:  stats.TotalCacheReadTokens,
+				TotalCacheWriteTokens: stats.TotalCacheWriteTokens,
+				TotalCost:             stats.TotalCost,
+				RequestCount:          stats.RequestCount,
+			}
+		},
+		Exit: func() { appInstance.QuitFromExtension() },
+		SetWidget: func(config extensions.WidgetConfig) {
+			kitInstance.Extensions().SetWidget(config)
+			go appInstance.NotifyWidgetUpdate()
+		},
+		RemoveWidget: func(id string) {
+			kitInstance.Extensions().RemoveWidget(id)
+			go appInstance.NotifyWidgetUpdate()
+		},
+		SetHeader: func(config extensions.HeaderFooterConfig) {
+			kitInstance.Extensions().SetHeader(config)
+			go appInstance.NotifyWidgetUpdate()
+		},
+		RemoveHeader: func() {
+			kitInstance.Extensions().RemoveHeader()
+			go appInstance.NotifyWidgetUpdate()
+		},
+		SetFooter: func(config extensions.HeaderFooterConfig) {
+			kitInstance.Extensions().SetFooter(config)
+			go appInstance.NotifyWidgetUpdate()
+		},
+		RemoveFooter: func() {
+			kitInstance.Extensions().RemoveFooter()
+			go appInstance.NotifyWidgetUpdate()
+		},
+		PromptSelect: func(config extensions.PromptSelectConfig) extensions.PromptSelectResult {
+			ch := make(chan app.PromptResponse, 1)
+			appInstance.SendPromptRequest(app.PromptRequestEvent{
+				PromptType: "select",
+				Message:    config.Message,
+				Options:    config.Options,
+				ResponseCh: ch,
+			})
+			resp := <-ch
+			if resp.Cancelled {
+				return extensions.PromptSelectResult{Cancelled: true}
+			}
+			return extensions.PromptSelectResult{Value: resp.Value, Index: resp.Index}
+		},
+		PromptConfirm: func(config extensions.PromptConfirmConfig) extensions.PromptConfirmResult {
+			ch := make(chan app.PromptResponse, 1)
+			def := "false"
+			if config.DefaultValue {
+				def = "true"
+			}
+			appInstance.SendPromptRequest(app.PromptRequestEvent{
+				PromptType: "confirm",
+				Message:    config.Message,
+				Default:    def,
+				ResponseCh: ch,
+			})
+			resp := <-ch
+			if resp.Cancelled {
+				return extensions.PromptConfirmResult{Cancelled: true}
+			}
+			return extensions.PromptConfirmResult{Value: resp.Confirmed}
+		},
+		PromptInput: func(config extensions.PromptInputConfig) extensions.PromptInputResult {
+			ch := make(chan app.PromptResponse, 1)
+			appInstance.SendPromptRequest(app.PromptRequestEvent{
+				PromptType:  "input",
+				Message:     config.Message,
+				Placeholder: config.Placeholder,
+				Default:     config.Default,
+				ResponseCh:  ch,
+			})
+			resp := <-ch
+			if resp.Cancelled {
+				return extensions.PromptInputResult{Cancelled: true}
+			}
+			return extensions.PromptInputResult{Value: resp.Value}
+		},
+		SetUIVisibility: func(v extensions.UIVisibility) {
+			kitInstance.Extensions().SetUIVisibility(v)
+			go appInstance.NotifyWidgetUpdate()
+		},
+		GetContextStats: func() extensions.ContextStats {
+			s := kitInstance.GetContextStats()
+			return extensions.ContextStats{
+				EstimatedTokens: s.EstimatedTokens,
+				ContextLimit:    s.ContextLimit,
+				UsagePercent:    s.UsagePercent,
+				MessageCount:    s.MessageCount,
+			}
+		},
+		SetEditor: func(config extensions.EditorConfig) {
+			kitInstance.Extensions().SetEditor(config)
+			// Always use a goroutine for NotifyWidgetUpdate: prog.Send()
+			// deadlocks if called synchronously from inside BubbleTea's
+			// Update() handler. All call sites use go-routines uniformly.
+			go appInstance.NotifyWidgetUpdate()
+		},
+		ResetEditor: func() {
+			kitInstance.Extensions().ResetEditor()
+			go appInstance.NotifyWidgetUpdate()
+		},
+		GetMessages: func() []extensions.SessionMessage {
+			return kitInstance.Extensions().GetSessionMessages()
+		},
+		GetSessionPath: func() string {
+			return kitInstance.GetSessionPath()
+		},
+		AppendEntry: func(entryType string, data string) (string, error) {
+			return kitInstance.Extensions().AppendEntry(entryType, data)
+		},
+		GetEntries: func(entryType string) []extensions.ExtensionEntry {
+			return kitInstance.Extensions().GetEntries(entryType)
+		},
+		SetEditorText: func(text string) {
+			appInstance.SetEditorTextFromExtension(text)
+		},
+		SetStatus: func(key string, text string, priority int) {
+			kitInstance.Extensions().SetStatus(extensions.StatusBarEntry{
+				Key:      key,
+				Text:     text,
+				Priority: priority,
+			})
+			go appInstance.NotifyWidgetUpdate()
+		},
+		RemoveStatus: func(key string) {
+			kitInstance.Extensions().RemoveStatus(key)
+			go appInstance.NotifyWidgetUpdate()
+		},
+		GetOption: func(name string) string {
+			return kitInstance.Extensions().GetOption(name)
+		},
+		SetOption: func(name string, value string) {
+			kitInstance.Extensions().SetOption(name, value)
+		},
+		SetModel: func(modelString string) error {
+			// Capture previous model for the ModelChange event.
+			previousModel := kitInstance.Extensions().GetContext().Model
+			err := kitInstance.SetModel(context.Background(), modelString)
+			if err != nil {
+				return err
+			}
+			// Notify TUI so it updates model in status bar.
+			p, m, _ := models.ParseModelString(modelString)
+			appInstance.NotifyModelChanged(p, m)
+			// Update the context's Model field so handlers see it.
+			kitInstance.Extensions().UpdateContextModel(modelString)
+			// Fire OnModelChange event to extensions.
+			kitInstance.Extensions().EmitModelChange(modelString, previousModel, "extension")
+			// Update usage tracker with new model info for correct token counting.
+			if usageTracker != nil {
+				newProvider, newModel, _ := models.ParseModelString(modelString)
+				if newProvider != "unknown" && newModel != "unknown" && newProvider != "ollama" {
+					registry := models.GetGlobalRegistry()
+					if modelInfo := registry.LookupModel(newProvider, newModel); modelInfo != nil {
+						// Check OAuth status for Anthropic models
+						isOAuth := false
+						if newProvider == "anthropic" {
+							_, source, err := auth.GetAnthropicAPIKey(viper.GetString("provider-api-key"))
+							if err == nil && strings.HasPrefix(source, "stored OAuth") {
+								isOAuth = true
+							}
+						}
+						usageTracker.UpdateModelInfo(modelInfo, newProvider, isOAuth)
+					}
+				}
+			}
+			return nil
+		},
+		GetAvailableModels: func() []extensions.ModelInfoEntry {
+			return kitInstance.GetAvailableModels()
+		},
+		EmitCustomEvent: func(name string, data string) {
+			kitInstance.Extensions().EmitCustomEvent(name, data)
+		},
+		Complete: func(req extensions.CompleteRequest) (extensions.CompleteResponse, error) {
+			return kitInstance.ExecuteCompletion(context.Background(), req)
+		},
+		SuspendTUI: func(callback func()) error {
+			return appInstance.SuspendTUI(callback)
+		},
+		RenderMessage: func(rendererName, content string) {
+			renderer := kitInstance.Extensions().GetMessageRenderer(rendererName)
+			if renderer == nil || renderer.Render == nil {
+				appInstance.PrintFromExtension("", content)
+				return
+			}
+			w, _, _ := term.GetSize(int(os.Stdout.Fd()))
+			if w == 0 {
+				w = 80
+			}
+			rendered := renderer.Render(content, w)
+			appInstance.PrintFromExtension("", rendered)
+		},
+		ReloadExtensions: func() error {
+			err := kitInstance.Extensions().Reload()
+			if err != nil {
+				return err
+			}
+			// Notify TUI that widgets/status/commands may have changed.
+			go appInstance.NotifyWidgetUpdate()
+			return nil
+		},
+		GetAllTools: func() []extensions.ToolInfo {
+			return kitInstance.Extensions().GetToolInfos()
+		},
+		SetActiveTools: func(names []string) {
+			kitInstance.Extensions().SetActiveTools(names)
+		},
+		RegisterTheme: func(name string, config extensions.ThemeColorConfig) {
+			tc := func(c extensions.ThemeColor) [2]string { return [2]string{c.Light, c.Dark} }
+			ui.RegisterThemeFromConfig(name,
+				tc(config.Primary), tc(config.Secondary),
+				tc(config.Success), tc(config.Warning),
+				tc(config.Error), tc(config.Info),
+				tc(config.Text), tc(config.Muted),
+				tc(config.VeryMuted), tc(config.Background),
+				tc(config.Border), tc(config.MutedBorder),
+				tc(config.System), tc(config.Tool),
+				tc(config.Accent), tc(config.Highlight),
+				tc(config.MdHeading), tc(config.MdLink),
+				tc(config.MdKeyword), tc(config.MdString),
+				tc(config.MdNumber), tc(config.MdComment),
+			)
+		},
+		SetTheme: func(name string) error {
+			return ui.ApplyTheme(name)
+		},
+		ListThemes: func() []string {
+			return ui.ListThemes()
+		},
+		ShowOverlay: func(config extensions.OverlayConfig) extensions.OverlayResult {
+			ch := make(chan app.OverlayResponse, 1)
+			appInstance.SendOverlayRequest(app.OverlayRequestEvent{
+				Title:       config.Title,
+				Content:     config.Content.Text,
+				Markdown:    config.Content.Markdown,
+				BorderColor: config.Style.BorderColor,
+				Background:  config.Style.Background,
+				Width:       config.Width,
+				MaxHeight:   config.MaxHeight,
+				Anchor:      string(config.Anchor),
+				Actions:     config.Actions,
+				ResponseCh:  ch,
+			})
+			resp := <-ch
+			if resp.Cancelled {
+				return extensions.OverlayResult{Cancelled: true, Index: -1}
+			}
+			return extensions.OverlayResult{
+				Action: resp.Action,
+				Index:  resp.Index,
+			}
+		},
+		SpawnSubagent: func(config extensions.SubagentConfig) (*extensions.SubagentHandle, *extensions.SubagentResult, error) {
+			return extbridge.SpawnSubagent(ctx, kitInstance, config)
+		},
+		// -------------------------------------------------------------------
+		// Tree Navigation API
+		// -------------------------------------------------------------------
+		GetTreeNode: func(entryID string) *extensions.TreeNode {
+			node := kitInstance.GetTreeNode(entryID)
+			if node == nil {
+				return nil
+			}
+			return &extensions.TreeNode{
+				ID:        node.ID,
+				ParentID:  node.ParentID,
+				Type:      node.Type,
+				Role:      node.Role,
+				Content:   node.Content,
+				Model:     node.Model,
+				Provider:  node.Provider,
+				Timestamp: node.Timestamp,
+				Children:  node.Children,
+			}
+		},
+		GetCurrentBranch: func() []extensions.TreeNode {
+			nodes := kitInstance.GetCurrentBranch()
+			result := make([]extensions.TreeNode, len(nodes))
+			for i, n := range nodes {
+				result[i] = extensions.TreeNode{
+					ID:        n.ID,
+					ParentID:  n.ParentID,
+					Type:      n.Type,
+					Role:      n.Role,
+					Content:   n.Content,
+					Model:     n.Model,
+					Provider:  n.Provider,
+					Timestamp: n.Timestamp,
+					Children:  n.Children,
+				}
+			}
+			return result
+		},
+		GetChildren: func(parentID string) []string {
+			return kitInstance.GetChildren(parentID)
+		},
+		NavigateTo: func(entryID string) extensions.TreeNavigationResult {
+			err := kitInstance.NavigateTo(entryID)
+			if err != nil {
+				return extensions.TreeNavigationResult{Success: false, Error: err.Error()}
+			}
+			return extensions.TreeNavigationResult{Success: true}
+		},
+		SummarizeBranch: func(fromID, toID string) string {
+			summary, _ := kitInstance.SummarizeBranch(fromID, toID)
+			return summary
+		},
+		CollapseBranch: func(fromID, toID, summary string) extensions.TreeNavigationResult {
+			err := kitInstance.CollapseBranch(fromID, toID, summary)
+			if err != nil {
+				return extensions.TreeNavigationResult{Success: false, Error: err.Error()}
+			}
+			return extensions.TreeNavigationResult{Success: true}
+		},
+
+		// -------------------------------------------------------------------
+		// Skill Loading API
+		// -------------------------------------------------------------------
+		LoadSkill: func(path string) (*extensions.Skill, string) {
+			s, err := kitInstance.LoadSkillForExtension(path)
+			return s, err
+		},
+		LoadSkillsFromDir: func(dir string) extensions.SkillLoadResult {
+			return kitInstance.LoadSkillsFromDirForExtension(dir)
+		},
+		DiscoverSkills: func() extensions.SkillLoadResult {
+			skills := kitInstance.DiscoverSkillsForExtension()
+			return extensions.SkillLoadResult{Skills: skills}
+		},
+		InjectSkillAsContext: func(skillName string) string {
+			skills := kitInstance.DiscoverSkillsForExtension()
+			for _, s := range skills {
+				if s.Name == skillName {
+					appInstance.Run(fmt.Sprintf("<skill name=%q>\n%s\n</skill>", s.Name, s.Content))
+					return ""
+				}
+			}
+			return fmt.Sprintf("skill not found: %s", skillName)
+		},
+		InjectRawSkillAsContext: func(path string) string {
+			s, err := kitInstance.LoadSkillForExtension(path)
+			if err != "" {
+				return err
+			}
+			appInstance.Run(fmt.Sprintf("<skill name=%q>\n%s\n</skill>", s.Name, s.Content))
+			return ""
+		},
+		GetAvailableSkills: func() []extensions.Skill {
+			return kitInstance.DiscoverSkillsForExtension()
+		},
+
+		// -------------------------------------------------------------------
+		// Template Parsing API
+		// -------------------------------------------------------------------
+		ParseTemplate: func(name, content string) extensions.PromptTemplate {
+			return kit.ParseTemplate(name, content)
+		},
+		RenderTemplate: func(tpl extensions.PromptTemplate, vars map[string]string) string {
+			return kit.RenderTemplate(tpl, vars)
+		},
+		ParseArguments: func(input string, pattern extensions.ArgumentPattern) extensions.ParseResult {
+			return kit.ParseArguments(input, pattern)
+		},
+		SimpleParseArguments: func(input string, count int) []string {
+			return kit.SimpleParseArguments(input, count)
+		},
+		EvaluateModelConditional: func(condition string) bool {
+			return kit.EvaluateModelConditional(kitInstance.Extensions().GetContext().Model, condition)
+		},
+		RenderWithModelConditionals: func(content string) string {
+			return kit.RenderWithModelConditionals(content, kitInstance.Extensions().GetContext().Model)
+		},
+
+		// -------------------------------------------------------------------
+		// Model Resolution API
+		// -------------------------------------------------------------------
+		ResolveModelChain: func(preferences []string) extensions.ModelResolutionResult {
+			return kit.ResolveModelChain(preferences)
+		},
+		GetModelCapabilities: func(model string) (extensions.ModelCapabilities, string) {
+			return kit.GetModelCapabilities(model)
+		},
+		CheckModelAvailable: func(model string) bool {
+			return kit.CheckModelAvailable(model)
+		},
+		GetCurrentProvider: func() string {
+			return kit.GetCurrentProvider(kitInstance.Extensions().GetContext().Model)
+		},
+		GetCurrentModelID: func() string {
+			return kit.GetCurrentModelID(kitInstance.Extensions().GetContext().Model)
+		},
+	}
+}

examples/extensions/subagent-monitor.go

@@ -13,8 +13,6 @@
 // - No channels in maps (Yaegi panics on range over map[string]chan)
 // - All ctx.* calls guarded with nil checks
 // - Simple data structures only
-// - The extension runner serializes handler calls per-extension, so
-//   concurrent subagent events cannot race on this shared state.
 package main
 
 import (
@@ -45,8 +43,7 @@ const (
 )
 
 // ---------------------------------------------------------------------------
-// Package-level state — safe because the runner serializes all handler
-// invocations for the same extension (per-extension reentrant mutex).
+// Package-level state - all simple types
 // ---------------------------------------------------------------------------
 
 var (
@@ -285,8 +282,8 @@ func Init(api ext.API) {
 
 		submonPushWidget()
 
-		// Remove the entry — build a new slice to avoid aliasing bugs
-		newEntries := make([]*submonEntry, 0, len(submonEntries))
+		// Remove the entry immediately (no goroutine to avoid races)
+		newEntries := submonEntries[:0]
 		for _, en := range submonEntries {
 			if en.callID != e.ToolCallID {
 				newEntries = append(newEntries, en)

examples/extensions/subagent-monitor_test.go

@@ -13,7 +13,7 @@ import (
 // without panicking and properly guards nil ctx calls.
 func TestSubagentMonitor_SessionStart(t *testing.T) {
 	harness := test.New(t)
-	harness.LoadFile("../../.kit/extensions/subagent-monitor.go")
+	harness.LoadFile("./subagent-monitor.go")
 
 	// Emit SessionStart - should not panic even with nil ctx functions
 	_, err := harness.Emit(extensions.SessionStartEvent{SessionID: "test-session"})
@@ -26,7 +26,7 @@ func TestSubagentMonitor_SessionStart(t *testing.T) {
 // creates entries and emits widget updates.
 func TestSubagentMonitor_SubagentLifecycle(t *testing.T) {
 	harness := test.New(t)
-	harness.LoadFile("../../.kit/extensions/subagent-monitor.go")
+	harness.LoadFile("./subagent-monitor.go")
 
 	// Start session
 	_, err := harness.Emit(extensions.SessionStartEvent{SessionID: "test-session"})
@@ -84,7 +84,7 @@ func TestSubagentMonitor_SubagentLifecycle(t *testing.T) {
 // TestSubagentMonitor_MultipleSubagents verifies multiple parallel subagents.
 func TestSubagentMonitor_MultipleSubagents(t *testing.T) {
 	harness := test.New(t)
-	harness.LoadFile("../../.kit/extensions/subagent-monitor.go")
+	harness.LoadFile("./subagent-monitor.go")
 
 	_, err := harness.Emit(extensions.SessionStartEvent{SessionID: "test-session"})
 	if err != nil {
@@ -134,7 +134,7 @@ func TestSubagentMonitor_MultipleSubagents(t *testing.T) {
 // subagents emit events concurrently from different goroutines.
 func TestSubagentMonitor_ConcurrentSubagents(t *testing.T) {
 	harness := test.New(t)
-	harness.LoadFile("../../.kit/extensions/subagent-monitor.go")
+	harness.LoadFile("./subagent-monitor.go")
 
 	_, err := harness.Emit(extensions.SessionStartEvent{SessionID: "test-session"})
 	if err != nil {
@@ -186,7 +186,7 @@ func TestSubagentMonitor_ConcurrentSubagents(t *testing.T) {
 // even with nil ctx functions.
 func TestSubagentMonitor_SessionShutdown(t *testing.T) {
 	harness := test.New(t)
-	harness.LoadFile("../../.kit/extensions/subagent-monitor.go")
+	harness.LoadFile("./subagent-monitor.go")
 
 	// Start then shutdown
 	_, err := harness.Emit(extensions.SessionStartEvent{SessionID: "test-session"})

go.mod

@@ -1,32 +1,32 @@
 module github.com/mark3labs/kit
 
-go 1.26.2
+go 1.26.3
 
 require (
 	charm.land/bubbles/v2 v2.1.0
 	charm.land/bubbletea/v2 v2.0.6
-	charm.land/fantasy v0.19.0
+	charm.land/fantasy v0.25.0
 	charm.land/huh/v2 v2.0.3
 	charm.land/lipgloss/v2 v2.0.3
-	github.com/alecthomas/chroma/v2 v2.23.1
+	github.com/alecthomas/chroma/v2 v2.26.1
 	github.com/atotto/clipboard v0.1.4
 	github.com/aymanbagabas/go-udiff v0.4.1
 	github.com/charmbracelet/fang v1.0.0
 	github.com/charmbracelet/log v1.0.0
 	github.com/charmbracelet/openai-go v0.0.0-20260319145158-d0740cc34266
-	github.com/charmbracelet/ultraviolet v0.0.0-20260420095748-421e4a7fa8d7
+	github.com/charmbracelet/ultraviolet v0.0.0-20260525132238-948f4557a654
 	github.com/charmbracelet/x/editor v0.2.0
 	github.com/clipperhouse/displaywidth v0.11.0
 	github.com/clipperhouse/uax29/v2 v2.7.0
-	github.com/coder/acp-go-sdk v0.12.0
-	github.com/fsnotify/fsnotify v1.9.0
+	github.com/coder/acp-go-sdk v0.13.0
+	github.com/fsnotify/fsnotify v1.10.1
 	github.com/indaco/herald v0.13.0
 	github.com/indaco/herald-md v0.3.0
-	github.com/mark3labs/mcp-go v0.49.0
+	github.com/mark3labs/mcp-go v0.54.1
 	github.com/spf13/cobra v1.10.2
 	github.com/spf13/viper v1.21.0
 	github.com/traefik/yaegi v0.16.1
-	golang.org/x/term v0.42.0
+	golang.org/x/term v0.43.0
 	gopkg.in/yaml.v3 v3.0.1
 )
 
@@ -37,21 +37,21 @@ require (
 	cloud.google.com/go/compute/metadata v0.9.0 // indirect
 	github.com/Azure/azure-sdk-for-go/sdk/azcore v1.21.1 // indirect
 	github.com/Azure/azure-sdk-for-go/sdk/internal v1.12.0 // indirect
-	github.com/aws/aws-sdk-go-v2 v1.41.6 // indirect
-	github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream v1.7.9 // indirect
-	github.com/aws/aws-sdk-go-v2/config v1.32.16 // indirect
-	github.com/aws/aws-sdk-go-v2/credentials v1.19.15 // indirect
-	github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.18.22 // indirect
-	github.com/aws/aws-sdk-go-v2/internal/configsources v1.4.22 // indirect
-	github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.7.22 // indirect
-	github.com/aws/aws-sdk-go-v2/internal/v4a v1.4.23 // indirect
-	github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.13.8 // indirect
-	github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.13.22 // indirect
-	github.com/aws/aws-sdk-go-v2/service/signin v1.0.10 // indirect
-	github.com/aws/aws-sdk-go-v2/service/sso v1.30.16 // indirect
-	github.com/aws/aws-sdk-go-v2/service/ssooidc v1.35.20 // indirect
-	github.com/aws/aws-sdk-go-v2/service/sts v1.42.0 // indirect
-	github.com/aws/smithy-go v1.25.0 // indirect
+	github.com/aws/aws-sdk-go-v2 v1.41.8 // indirect
+	github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream v1.7.10 // indirect
+	github.com/aws/aws-sdk-go-v2/config v1.32.19 // indirect
+	github.com/aws/aws-sdk-go-v2/credentials v1.19.18 // indirect
+	github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.18.24 // indirect
+	github.com/aws/aws-sdk-go-v2/internal/configsources v1.4.24 // indirect
+	github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.7.24 // indirect
+	github.com/aws/aws-sdk-go-v2/internal/v4a v1.4.25 // indirect
+	github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.13.9 // indirect
+	github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.13.24 // indirect
+	github.com/aws/aws-sdk-go-v2/service/signin v1.1.0 // indirect
+	github.com/aws/aws-sdk-go-v2/service/sso v1.30.18 // indirect
+	github.com/aws/aws-sdk-go-v2/service/ssooidc v1.36.1 // indirect
+	github.com/aws/aws-sdk-go-v2/service/sts v1.42.2 // indirect
+	github.com/aws/smithy-go v1.26.0 // indirect
 	github.com/catppuccin/go v0.3.0 // indirect
 	github.com/cespare/xxhash/v2 v2.3.0 // indirect
 	github.com/charmbracelet/anthropic-sdk-go v0.0.0-20260223140439-63879b0b8dab // indirect
@@ -59,44 +59,46 @@ require (
 	github.com/charmbracelet/harmonica v0.2.0 // indirect
 	github.com/charmbracelet/lipgloss v1.1.1-0.20250404203927-76690c660834 // indirect
 	github.com/charmbracelet/x/cellbuf v0.0.15 // indirect
-	github.com/charmbracelet/x/exp/charmtone v0.0.0-20260420102150-fe550f2efce5 // indirect
+	github.com/charmbracelet/x/exp/charmtone v0.0.0-20260527151214-009e6338d40d // indirect
 	github.com/charmbracelet/x/exp/ordered v0.1.0 // indirect
-	github.com/charmbracelet/x/exp/slice v0.0.0-20260420102150-fe550f2efce5 // indirect
+	github.com/charmbracelet/x/exp/slice v0.0.0-20260527151214-009e6338d40d // indirect
 	github.com/charmbracelet/x/exp/strings v0.1.0 // indirect
 	github.com/charmbracelet/x/json v0.2.0 // indirect
 	github.com/charmbracelet/x/termios v0.1.1 // indirect
 	github.com/charmbracelet/x/windows v0.2.2 // indirect
 	github.com/dlclark/regexp2 v1.12.0 // indirect
+	github.com/dlclark/regexp2/v2 v2.1.1 // indirect
 	github.com/dustin/go-humanize v1.0.1 // indirect
 	github.com/felixge/httpsnoop v1.0.4 // indirect
-	github.com/go-json-experiment/json v0.0.0-20260214004413-d219187c3433 // indirect
+	github.com/go-json-experiment/json v0.0.0-20260520185125-572e7c383686 // indirect
 	github.com/go-logfmt/logfmt v0.6.1 // indirect
 	github.com/go-logr/logr v1.4.3 // indirect
 	github.com/go-logr/stdr v1.2.2 // indirect
 	github.com/go-viper/mapstructure/v2 v2.5.0 // indirect
 	github.com/goccy/go-yaml v1.19.2 // indirect
 	github.com/google/go-cmp v0.7.0 // indirect
-	github.com/google/jsonschema-go v0.4.2 // indirect
+	github.com/google/jsonschema-go v0.4.3 // indirect
 	github.com/google/s2a-go v0.1.9 // indirect
 	github.com/google/uuid v1.6.0 // indirect
-	github.com/googleapis/enterprise-certificate-proxy v0.3.15 // indirect
+	github.com/googleapis/enterprise-certificate-proxy v0.3.16 // indirect
 	github.com/googleapis/gax-go/v2 v2.22.0 // indirect
 	github.com/gorilla/websocket v1.5.3 // indirect
-	github.com/kaptinlin/go-i18n v0.4.2 // indirect
-	github.com/kaptinlin/jsonpointer v0.4.18 // indirect
-	github.com/kaptinlin/jsonschema v0.7.8 // indirect
-	github.com/kaptinlin/messageformat-go v0.5.2 // indirect
+	github.com/kaptinlin/go-i18n v0.4.5 // indirect
+	github.com/kaptinlin/jsonpointer v0.4.25 // indirect
+	github.com/kaptinlin/jsonschema v0.7.13 // indirect
+	github.com/kaptinlin/messageformat-go v0.6.0 // indirect
 	github.com/mitchellh/hashstructure/v2 v2.0.2 // indirect
 	github.com/muesli/mango v0.2.0 // indirect
 	github.com/muesli/mango-cobra v1.3.0 // indirect
 	github.com/muesli/mango-pflag v0.2.0 // indirect
 	github.com/muesli/roff v0.1.0 // indirect
-	github.com/pelletier/go-toml/v2 v2.3.0 // indirect
+	github.com/pelletier/go-toml/v2 v2.3.1 // indirect
 	github.com/sagikazarmark/locafero v0.12.0 // indirect
+	github.com/santhosh-tekuri/jsonschema/v6 v6.0.2 // indirect
 	github.com/spf13/afero v1.15.0 // indirect
 	github.com/spf13/cast v1.10.0 // indirect
 	github.com/subosito/gotenv v1.6.0 // indirect
-	github.com/tidwall/gjson v1.18.0 // indirect
+	github.com/tidwall/gjson v1.19.0 // indirect
 	github.com/tidwall/match v1.2.0 // indirect
 	github.com/tidwall/pretty v1.2.1 // indirect
 	github.com/tidwall/sjson v1.2.5 // indirect
@@ -104,21 +106,21 @@ require (
 	github.com/yosida95/uritemplate/v3 v3.0.2 // indirect
 	github.com/yuin/goldmark v1.8.2 // indirect
 	go.opentelemetry.io/auto/sdk v1.2.1 // indirect
-	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.68.0 // indirect
-	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.68.0 // indirect
-	go.opentelemetry.io/otel v1.43.0 // indirect
-	go.opentelemetry.io/otel/metric v1.43.0 // indirect
-	go.opentelemetry.io/otel/trace v1.43.0 // indirect
+	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.69.0 // indirect
+	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.69.0 // indirect
+	go.opentelemetry.io/otel v1.44.0 // indirect
+	go.opentelemetry.io/otel/metric v1.44.0 // indirect
+	go.opentelemetry.io/otel/trace v1.44.0 // indirect
 	go.yaml.in/yaml/v3 v3.0.4 // indirect
-	golang.org/x/crypto v0.50.0 // indirect
-	golang.org/x/exp v0.0.0-20260410095643-746e56fc9e2f // indirect
-	golang.org/x/net v0.53.0 // indirect
+	golang.org/x/crypto v0.52.0 // indirect
+	golang.org/x/exp v0.0.0-20260528193900-50dc527dd6c7 // indirect
+	golang.org/x/net v0.55.0 // indirect
 	golang.org/x/oauth2 v0.36.0 // indirect
 	golang.org/x/time v0.15.0 // indirect
-	google.golang.org/api v0.276.0 // indirect
-	google.golang.org/genai v1.54.0 // indirect
-	google.golang.org/genproto/googleapis/rpc v0.0.0-20260420184626-e10c466a9529 // indirect
-	google.golang.org/grpc v1.80.0 // indirect
+	google.golang.org/api v0.282.0 // indirect
+	google.golang.org/genai v1.58.0 // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20260526163538-3dc84a4a5aaa // indirect
+	google.golang.org/grpc v1.81.1 // indirect
 	google.golang.org/protobuf v1.36.11 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
 )
@@ -129,13 +131,13 @@ require (
 	github.com/charmbracelet/x/term v0.2.2 // indirect
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
 	github.com/lucasb-eyer/go-colorful v1.4.0 // indirect
-	github.com/mattn/go-isatty v0.0.21 // indirect
+	github.com/mattn/go-isatty v0.0.22 // indirect
 	github.com/mattn/go-runewidth v0.0.23 // indirect
 	github.com/muesli/cancelreader v0.2.2 // indirect
 	github.com/muesli/termenv v0.16.0 // indirect
 	github.com/rivo/uniseg v0.4.7 // indirect
 	github.com/spf13/pflag v1.0.10
 	golang.org/x/sync v0.20.0 // indirect
-	golang.org/x/sys v0.43.0 // indirect
-	golang.org/x/text v0.36.0
+	golang.org/x/sys v0.45.0 // indirect
+	golang.org/x/text v0.37.0
 )

go.sum

@@ -2,8 +2,8 @@ charm.land/bubbles/v2 v2.1.0 h1:YSnNh5cPYlYjPxRrzs5VEn3vwhtEn3jVGRBT3M7/I0g=
 charm.land/bubbles/v2 v2.1.0/go.mod h1:l97h4hym2hvWBVfmJDtrEHHCtkIKeTEb3TTJ4ZOB3wY=
 charm.land/bubbletea/v2 v2.0.6 h1:UHN/91OyuhaOFGSrBXQ/hMZD8IO1Uc4BvHlgHXL2WJo=
 charm.land/bubbletea/v2 v2.0.6/go.mod h1:MH/D8ZLlN3op37vQvijKuU29g3rqTp+aQapURFonF9g=
-charm.land/fantasy v0.19.0 h1:fnNXkIJ/xcIW3sdVtWxjtQGpWWe8pDGhBCWSHkgbrd0=
-charm.land/fantasy v0.19.0/go.mod h1:V9cCIUMZB9g3Bq40aKEY8xBNzDd48EdfHp2OMS0uzWs=
+charm.land/fantasy v0.25.0 h1:oXOWY1ivmTSnhYGzAolscF8zKtavWZyBWv0LHRSwN5Q=
+charm.land/fantasy v0.25.0/go.mod h1:8QrWUzIcKwZQP+aAnC9vLu3iID6hu9/Jt+rPMiieBkc=
 charm.land/huh/v2 v2.0.3 h1:2cJsMqEPwSywGHvdlKsJyQKPtSJLVnFKyFbsYZTlLkU=
 charm.land/huh/v2 v2.0.3/go.mod h1:93eEveeeqn47MwiC3tf+2atZ2l7Is88rAtmZNZ8x9Wc=
 charm.land/lipgloss/v2 v2.0.3 h1:yM2zJ4Cf5Y51b7RHIwioil4ApI/aypFXXVHSwlM6RzU=
@@ -28,42 +28,42 @@ github.com/MakeNowJust/heredoc v1.0.0 h1:cXCdzVdstXyiTqTvfqk9SDHpKNjxuom+DOlyEeQ
 github.com/MakeNowJust/heredoc v1.0.0/go.mod h1:mG5amYoWBHf8vpLOuehzbGGw0EHxpZZ6lCpQ4fNJ8LE=
 github.com/alecthomas/assert/v2 v2.11.0 h1:2Q9r3ki8+JYXvGsDyBXwH3LcJ+WK5D0gc5E8vS6K3D0=
 github.com/alecthomas/assert/v2 v2.11.0/go.mod h1:Bze95FyfUr7x34QZrjL+XP+0qgp/zg8yS+TtBj1WA3k=
-github.com/alecthomas/chroma/v2 v2.23.1 h1:nv2AVZdTyClGbVQkIzlDm/rnhk1E9bU9nXwmZ/Vk/iY=
-github.com/alecthomas/chroma/v2 v2.23.1/go.mod h1:NqVhfBR0lte5Ouh3DcthuUCTUpDC9cxBOfyMbMQPs3o=
+github.com/alecthomas/chroma/v2 v2.26.1 h1:2X21EdxGZNv5GF9mG5u+uzc02GCFyGxbcBm3Grd9A78=
+github.com/alecthomas/chroma/v2 v2.26.1/go.mod h1:lxhRRa9H4hPmRLOOdYga4zkQIQjq3dtrrdwQeCfu78Y=
 github.com/alecthomas/repr v0.5.2 h1:SU73FTI9D1P5UNtvseffFSGmdNci/O6RsqzeXJtP0Qs=
 github.com/alecthomas/repr v0.5.2/go.mod h1:Fr0507jx4eOXV7AlPV6AVZLYrLIuIeSOWtW57eE/O/4=
 github.com/atotto/clipboard v0.1.4 h1:EH0zSVneZPSuFR11BlR9YppQTVDbh5+16AmcJi4g1z4=
 github.com/atotto/clipboard v0.1.4/go.mod h1:ZY9tmq7sm5xIbd9bOK4onWV4S6X0u6GY7Vn0Yu86PYI=
-github.com/aws/aws-sdk-go-v2 v1.41.6 h1:1AX0AthnBQzMx1vbmir3Y4WsnJgiydmnJjiLu+LvXOg=
-github.com/aws/aws-sdk-go-v2 v1.41.6/go.mod h1:dy0UzBIfwSeot4grGvY1AqFWN5zgziMmWGzysDnHFcQ=
-github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream v1.7.9 h1:adBsCIIpLbLmYnkQU+nAChU5yhVTvu5PerROm+/Kq2A=
-github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream v1.7.9/go.mod h1:uOYhgfgThm/ZyAuJGNQ5YgNyOlYfqnGpTHXvk3cpykg=
-github.com/aws/aws-sdk-go-v2/config v1.32.16 h1:Q0iQ7quUgJP0F/SCRTieScnaMdXr9h/2+wze1u3cNeM=
-github.com/aws/aws-sdk-go-v2/config v1.32.16/go.mod h1:duCCnJEFqpt2RC6no1iK6q+8HpwOAkiUua0pY507dQc=
-github.com/aws/aws-sdk-go-v2/credentials v1.19.15 h1:fyvgWTszojq8hEnMi8PPBTvZdTtEVmAVyo+NFLHBhH4=
-github.com/aws/aws-sdk-go-v2/credentials v1.19.15/go.mod h1:gJiYyMOjNg8OEdRWOf3CrFQxM2a98qmrtjx1zuiQfB8=
-github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.18.22 h1:IOGsJ1xVWhsi+ZO7/NW8OuZZBtMJLZbk4P5HDjJO0jQ=
-github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.18.22/go.mod h1:b+hYdbU+jGKfXE8kKM6g1+h+L/Go3vMvzlxBsiuGsxg=
-github.com/aws/aws-sdk-go-v2/internal/configsources v1.4.22 h1:GmLa5Kw1ESqtFpXsx5MmC84QWa/ZrLZvlJGa2y+4kcQ=
-github.com/aws/aws-sdk-go-v2/internal/configsources v1.4.22/go.mod h1:6sW9iWm9DK9YRpRGga/qzrzNLgKpT2cIxb7Vo2eNOp0=
-github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.7.22 h1:dY4kWZiSaXIzxnKlj17nHnBcXXBfac6UlsAx2qL6XrU=
-github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.7.22/go.mod h1:KIpEUx0JuRZLO7U6cbV204cWAEco2iC3l061IxlwLtI=
-github.com/aws/aws-sdk-go-v2/internal/v4a v1.4.23 h1:FPXsW9+gMuIeKmz7j6ENWcWtBGTe1kH8r9thNt5Uxx4=
-github.com/aws/aws-sdk-go-v2/internal/v4a v1.4.23/go.mod h1:7J8iGMdRKk6lw2C+cMIphgAnT8uTwBwNOsGkyOCm80U=
-github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.13.8 h1:HtOTYcbVcGABLOVuPYaIihj6IlkqubBwFj10K5fxRek=
-github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.13.8/go.mod h1:VsK9abqQeGlzPgUr+isNWzPlK2vKe9INMLWnY65f5Xs=
-github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.13.22 h1:PUmZeJU6Y1Lbvt9WFuJ0ugUK2xn6hIWUBBbKuOWF30s=
-github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.13.22/go.mod h1:nO6egFBoAaoXze24a2C0NjQCvdpk8OueRoYimvEB9jo=
-github.com/aws/aws-sdk-go-v2/service/signin v1.0.10 h1:a1Fq/KXn75wSzoJaPQTgZO0wHGqE9mjFnylnqEPTchA=
-github.com/aws/aws-sdk-go-v2/service/signin v1.0.10/go.mod h1:p6+MXNxW7IA6dMgHfTAzljuwSKD0NCm/4lbS4t6+7vI=
-github.com/aws/aws-sdk-go-v2/service/sso v1.30.16 h1:x6bKbmDhsgSZwv6q19wY/u3rLk/3FGjJWyqKcIRufpE=
-github.com/aws/aws-sdk-go-v2/service/sso v1.30.16/go.mod h1:CudnEVKRtLn0+3uMV0yEXZ+YZOKnAtUJ5DmDhilVnIw=
-github.com/aws/aws-sdk-go-v2/service/ssooidc v1.35.20 h1:oK/njaL8GtyEihkWMD4k3VgHCT64RQKkZwh0DG5j8ak=
-github.com/aws/aws-sdk-go-v2/service/ssooidc v1.35.20/go.mod h1:JHs8/y1f3zY7U5WcuzoJ/yAYGYtNIVPKLIbp61euvmg=
-github.com/aws/aws-sdk-go-v2/service/sts v1.42.0 h1:ks8KBcZPh3PYISr5dAiXCM5/Thcuxk8l+PG4+A0exds=
-github.com/aws/aws-sdk-go-v2/service/sts v1.42.0/go.mod h1:pFw33T0WLvXU3rw1WBkpMlkgIn54eCB5FYLhjDc9Foo=
-github.com/aws/smithy-go v1.25.0 h1:Sz/XJ64rwuiKtB6j98nDIPyYrV1nVNJ4YU74gttcl5U=
-github.com/aws/smithy-go v1.25.0/go.mod h1:YE2RhdIuDbA5E5bTdciG9KrW3+TiEONeUWCqxX9i1Fc=
+github.com/aws/aws-sdk-go-v2 v1.41.8 h1:sRs7nG6/RiEBZ/K5UO2sNw0w40U02Nmz1VtARloTZXk=
+github.com/aws/aws-sdk-go-v2 v1.41.8/go.mod h1:4LAfZOPHNVNQEckOACQx60Y8pSRjIkNZQz1w92xpMJc=
+github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream v1.7.10 h1:gx1AwW1Iyk9Z9dD9F4akX5gnN3QZwUB20GGKH/I+Rho=
+github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream v1.7.10/go.mod h1:qqY157uZoqm5OXq/amuaBJyC9hgBCBQnsaWnPe905GY=
+github.com/aws/aws-sdk-go-v2/config v1.32.19 h1:qRhIJMbevHUvIE7X4TK8N8zye5+5AhapcslPrvB+qKE=
+github.com/aws/aws-sdk-go-v2/config v1.32.19/go.mod h1:RbJ24nfoya63+Mf5VI+CGCGk9vEdv28xPeii+gojRYs=
+github.com/aws/aws-sdk-go-v2/credentials v1.19.18 h1:GcXQz2M/0ZvMo0v5DakUqbDBeBM1ZNaivkolEF4Esgw=
+github.com/aws/aws-sdk-go-v2/credentials v1.19.18/go.mod h1:sHJ06tMGcD3ZpmMyJqV+VBsGilhSIZPIN+ZFy5Dg0C4=
+github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.18.24 h1:FQm5ApnyzkuJdXLGskPce83CK1CQKC4RUnIHKVe4BU4=
+github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.18.24/go.mod h1:JsC7dqQc55MlZ5mvNsDMMge71u8pVcSzU3RNz2h/5yQ=
+github.com/aws/aws-sdk-go-v2/internal/configsources v1.4.24 h1:u6kJU2i0va1AgtJsH3RdWKWqHULlTh7zHwb35Womf74=
+github.com/aws/aws-sdk-go-v2/internal/configsources v1.4.24/go.mod h1:7GY+xLcXOFUpCkNwDReft9qOAVg54A4/AnjHIU7sSAY=
+github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.7.24 h1:Xhbcf3KugX6vX7SDyUK205Oicyfg7EGuvoVNyP5L6DM=
+github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.7.24/go.mod h1:rwDgb2HNOGZsnTHylOUedM7Vnl+bCfnXDqUNPsFWYfk=
+github.com/aws/aws-sdk-go-v2/internal/v4a v1.4.25 h1:54CTMmlJ71Rk2dYvM9qZOob+39wjlVja2zDLxCu69Ew=
+github.com/aws/aws-sdk-go-v2/internal/v4a v1.4.25/go.mod h1:BZaHqxsS9vN1fvV5EfEl0OBLOk5+AajWsMu6MjqnZB4=
+github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.13.9 h1:FLudkZLt5ci0ozzgkVo8BJGwvqNaZbTWb3UcucAateA=
+github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.13.9/go.mod h1:w7wZ/s9qK7c8g4al+UyoF1Sp/Z45UwMGcqIzLWVQHWk=
+github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.13.24 h1:CQW2FTrflfoslYWLf3fv7vG28Q219+v8YJS5QTQb2+Y=
+github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.13.24/go.mod h1:Xfx13T+u3nH6EEzgl9fBSO6nDRmze1FvnZNYkctQ2zw=
+github.com/aws/aws-sdk-go-v2/service/signin v1.1.0 h1:yQo3eZ5qFaL1sJWqs1nL6j3yPHA2/R7c6tQ4T+0IO10=
+github.com/aws/aws-sdk-go-v2/service/signin v1.1.0/go.mod h1:3Zzou41Qt/ueXfIzHvTEjDNuR5IjCUBVF01SNhrt1e8=
+github.com/aws/aws-sdk-go-v2/service/sso v1.30.18 h1:ApLTFdAZfDhZSiY5uskwECKHkSNNF83y2Ru2r7SezWA=
+github.com/aws/aws-sdk-go-v2/service/sso v1.30.18/go.mod h1:A9K9qx2l6nK89hp+a350FdGfRkrkH5HdiEjHbiy/Q/c=
+github.com/aws/aws-sdk-go-v2/service/ssooidc v1.36.1 h1:4VD7TIZOGzehrgQ8vDE+1c6BQW4ErZPGY8ohZT5LXEE=
+github.com/aws/aws-sdk-go-v2/service/ssooidc v1.36.1/go.mod h1:er0SFJfdV89Rit5hIJu/EXtv+qC2XMnxoksLmcUFkqM=
+github.com/aws/aws-sdk-go-v2/service/sts v1.42.2 h1:XKnxlM4KZH1gktcsh3zSWc7GW4KivEv/OkifmHOhCUY=
+github.com/aws/aws-sdk-go-v2/service/sts v1.42.2/go.mod h1:KJYmkQaFB3SUW2j3aBkPsxNmAb4ZsSOvbvCpuxzHJA0=
+github.com/aws/smithy-go v1.26.0 h1:9ouqbi+NyKP7fV3Te7UElCwdAb6Y8uk7LGwPE5tVe/s=
+github.com/aws/smithy-go v1.26.0/go.mod h1:YE2RhdIuDbA5E5bTdciG9KrW3+TiEONeUWCqxX9i1Fc=
 github.com/aymanbagabas/go-osc52/v2 v2.0.1 h1:HwpRHbFMcZLEVr42D4p7XBqjyuxQH5SMiErDT4WkJ2k=
 github.com/aymanbagabas/go-osc52/v2 v2.0.1/go.mod h1:uYgXzlJ7ZpABp8OJ+exZzJJhRNQ2ASbcXHWsFqH8hp8=
 github.com/aymanbagabas/go-udiff v0.4.1 h1:OEIrQ8maEeDBXQDoGCbbTTXYJMYRCRO1fnodZ12Gv5o=
@@ -86,8 +86,8 @@ github.com/charmbracelet/log v1.0.0 h1:HVVVMmfOorfj3BA9i8X8UL69Hoz9lI0PYwXfJvOdR
 github.com/charmbracelet/log v1.0.0/go.mod h1:uYgY3SmLpwJWxmlrPwXvzVYujxis1vAKRV/0VQB7yWA=
 github.com/charmbracelet/openai-go v0.0.0-20260319145158-d0740cc34266 h1:BW/sZtyd1JyYy0h5adMm3tzpNyL857LWjuTRET6OhpY=
 github.com/charmbracelet/openai-go v0.0.0-20260319145158-d0740cc34266/go.mod h1:1DahUaExbUZx/jD+FNT2PKP4L9rLE5+ZBRuI8mZjd/E=
-github.com/charmbracelet/ultraviolet v0.0.0-20260420095748-421e4a7fa8d7 h1:PbFxahSfyADcQOp+7WxbeqN3wX37KA/Rk+EXOW1xS9Q=
-github.com/charmbracelet/ultraviolet v0.0.0-20260420095748-421e4a7fa8d7/go.mod h1:3YdTxlnV/L0bQ3VN8WOSw8doF7LZV/xawUQ4MuAPDvo=
+github.com/charmbracelet/ultraviolet v0.0.0-20260525132238-948f4557a654 h1:FpSYhY28ucg9ZRr+2wj67FAQ0Ey5yiK0072PmRDJNek=
+github.com/charmbracelet/ultraviolet v0.0.0-20260525132238-948f4557a654/go.mod h1:hFpumms29Smx3LStRfku8vcCTBe1Kq8aCXtHUJa3mjY=
 github.com/charmbracelet/x/ansi v0.11.7 h1:kzv1kJvjg2S3r9KHo8hDdHFQLEqn4RBCb39dAYC84jI=
 github.com/charmbracelet/x/ansi v0.11.7/go.mod h1:9qGpnAVYz+8ACONkZBUWPtL7lulP9No6p1epAihUZwQ=
 github.com/charmbracelet/x/cellbuf v0.0.15 h1:ur3pZy0o6z/R7EylET877CBxaiE1Sp1GMxoFPAIztPI=
@@ -98,14 +98,14 @@ github.com/charmbracelet/x/editor v0.2.0 h1:7XLUKtaRaB8jN7bWU2p2UChiySyaAuIfYiIR
 github.com/charmbracelet/x/editor v0.2.0/go.mod h1:p3oQ28TSL3YPd+GKJ1fHWcp+7bVGpedHpXmo0D6t1dY=
 github.com/charmbracelet/x/errors v0.0.0-20240508181413-e8d8b6e2de86 h1:JSt3B+U9iqk37QUU2Rvb6DSBYRLtWqFqfxf8l5hOZUA=
 github.com/charmbracelet/x/errors v0.0.0-20240508181413-e8d8b6e2de86/go.mod h1:2P0UgXMEa6TsToMSuFqKFQR+fZTO9CNGUNokkPatT/0=
-github.com/charmbracelet/x/exp/charmtone v0.0.0-20260420102150-fe550f2efce5 h1:3ElWZRQqSRqML2P/r2TmuSkdXPMDI+Jg3f0bGA6Ekg4=
-github.com/charmbracelet/x/exp/charmtone v0.0.0-20260420102150-fe550f2efce5/go.mod h1:nsExn0DGyX0lh9LwLHTn2Gg+hafdzfSXnC+QmEJTZFY=
+github.com/charmbracelet/x/exp/charmtone v0.0.0-20260527151214-009e6338d40d h1:sMilwx1YIYTrQva6jsB522AoRYAerNaDIKP4ZPtUq0A=
+github.com/charmbracelet/x/exp/charmtone v0.0.0-20260527151214-009e6338d40d/go.mod h1:nsExn0DGyX0lh9LwLHTn2Gg+hafdzfSXnC+QmEJTZFY=
 github.com/charmbracelet/x/exp/golden v0.0.0-20250806222409-83e3a29d542f h1:pk6gmGpCE7F3FcjaOEKYriCvpmIN4+6OS/RD0vm4uIA=
 github.com/charmbracelet/x/exp/golden v0.0.0-20250806222409-83e3a29d542f/go.mod h1:IfZAMTHB6XkZSeXUqriemErjAWCCzT0LwjKFYCZyw0I=
 github.com/charmbracelet/x/exp/ordered v0.1.0 h1:55/qLwjIh0gL0Vni+QAWk7T/qRVP6sBf+2agPBgnOFE=
 github.com/charmbracelet/x/exp/ordered v0.1.0/go.mod h1:5UHwmG+is5THxMyCJHNPCn2/ecI07aKNrW+LcResjJ8=
-github.com/charmbracelet/x/exp/slice v0.0.0-20260420102150-fe550f2efce5 h1:QqpW1CPNAnOpM3Nj0X7IT2IFlR90bLdAkO5+A3Hwbi4=
-github.com/charmbracelet/x/exp/slice v0.0.0-20260420102150-fe550f2efce5/go.mod h1:vqEfX6xzqW1pKKZUUiFOKg0OQ7bCh54Q2vR/tserrRA=
+github.com/charmbracelet/x/exp/slice v0.0.0-20260527151214-009e6338d40d h1:RxcAR+vJCoD8QqT1cqLtkQKw+1cqvjqnu5IpPqYzPco=
+github.com/charmbracelet/x/exp/slice v0.0.0-20260527151214-009e6338d40d/go.mod h1:vqEfX6xzqW1pKKZUUiFOKg0OQ7bCh54Q2vR/tserrRA=
 github.com/charmbracelet/x/exp/strings v0.1.0 h1:i69S2XI7uG1u4NLGeJPSYU++Nmjvpo9nwd6aoEm7gkA=
 github.com/charmbracelet/x/exp/strings v0.1.0/go.mod h1:/ehtMPNh9K4odGFkqYJKpIYyePhdp1hLBRvyY4bWkH8=
 github.com/charmbracelet/x/json v0.2.0 h1:DqB+ZGx2h+Z+1s98HOuOyli+i97wsFQIxP2ZQANTPrQ=
@@ -124,8 +124,8 @@ github.com/clipperhouse/uax29/v2 v2.7.0 h1:+gs4oBZ2gPfVrKPthwbMzWZDaAFPGYK72F0NJ
 github.com/clipperhouse/uax29/v2 v2.7.0/go.mod h1:EFJ2TJMRUaplDxHKj1qAEhCtQPW2tJSwu5BF98AuoVM=
 github.com/cncf/xds/go v0.0.0-20260202195803-dba9d589def2 h1:aBangftG7EVZoUb69Os8IaYg++6uMOdKK83QtkkvJik=
 github.com/cncf/xds/go v0.0.0-20260202195803-dba9d589def2/go.mod h1:qwXFYgsP6T7XnJtbKlf1HP8AjxZZyzxMmc+Lq5GjlU4=
-github.com/coder/acp-go-sdk v0.12.0 h1:GoIC6RrkPMBIVQ3ckSkl+bO/ERV/IRK6clBdZmx4Uf4=
-github.com/coder/acp-go-sdk v0.12.0/go.mod h1:yKzM/3R9uELp4+nBAwwtkS0aN1FOFjo11CNPy37yFko=
+github.com/coder/acp-go-sdk v0.13.0 h1:IAKBDIbe/iBfKAGikeIndzb8fowt4ioD+gCtSU4HwMA=
+github.com/coder/acp-go-sdk v0.13.0/go.mod h1:yKzM/3R9uELp4+nBAwwtkS0aN1FOFjo11CNPy37yFko=
 github.com/cpuguy83/go-md2man/v2 v2.0.6/go.mod h1:oOW0eioCTA6cOiMLiUPZOpcVxMig6NIQQ7OS05n1F4g=
 github.com/creack/pty v1.1.24 h1:bJrF4RRfyJnbTJqzRLHzcGaZK1NeM5kTC9jGgovnR1s=
 github.com/creack/pty v1.1.24/go.mod h1:08sCNb52WyoAwi2QDyzUCTgcvVFhUzewun7wtTfvcwE=
@@ -133,6 +133,8 @@ github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc h1:U9qPSI2PIWSS1
 github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/dlclark/regexp2 v1.12.0 h1:0j4c5qQmnC6XOWNjP3PIXURXN2gWx76rd3KvgdPkCz8=
 github.com/dlclark/regexp2 v1.12.0/go.mod h1:DHkYz0B9wPfa6wondMfaivmHpzrQ3v9q8cnmRbL6yW8=
+github.com/dlclark/regexp2/v2 v2.1.1 h1:LCUGyd9Wf+r+VVOl8Ny38JTpWJcAsdVnCIuhhtthmKw=
+github.com/dlclark/regexp2/v2 v2.1.1/go.mod h1:avUrQvPaLz2DrFNHJF0taWAFFX2C1GMSSoeiqFjcBmU=
 github.com/dnaeon/go-vcr v1.2.0 h1:zHCHvJYTMh1N7xnV7zf1m1GPBF9Ad0Jk/whtQ1663qI=
 github.com/dnaeon/go-vcr v1.2.0/go.mod h1:R4UdLID7HZT3taECzJs4YgbbH6PIGXB6W/sc5OLb6RQ=
 github.com/dustin/go-humanize v1.0.1 h1:GzkhY7T5VNhEkwH0PVJgjz+fX1rhBrR7pRT3mDkpeCY=
@@ -146,10 +148,10 @@ github.com/felixge/httpsnoop v1.0.4 h1:NFTV2Zj1bL4mc9sqWACXbQFVBBg2W3GPvqp8/ESS2
 github.com/felixge/httpsnoop v1.0.4/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
 github.com/frankban/quicktest v1.14.6 h1:7Xjx+VpznH+oBnejlPUj8oUpdxnVs4f8XU8WnHkI4W8=
 github.com/frankban/quicktest v1.14.6/go.mod h1:4ptaffx2x8+WTWXmUCuVU6aPUX1/Mz7zb5vbUoiM6w0=
-github.com/fsnotify/fsnotify v1.9.0 h1:2Ml+OJNzbYCTzsxtv8vKSFD9PbJjmhYF14k/jKC7S9k=
-github.com/fsnotify/fsnotify v1.9.0/go.mod h1:8jBTzvmWwFyi3Pb8djgCCO5IBqzKJ/Jwo8TRcHyHii0=
-github.com/go-json-experiment/json v0.0.0-20260214004413-d219187c3433 h1:vymEbVwYFP/L05h5TKQxvkXoKxNvTpjxYKdF1Nlwuao=
-github.com/go-json-experiment/json v0.0.0-20260214004413-d219187c3433/go.mod h1:tphK2c80bpPhMOI4v6bIc2xWywPfbqi1Z06+RcrMkDg=
+github.com/fsnotify/fsnotify v1.10.1 h1:b0/UzAf9yR5rhf3RPm9gf3ehBPpf0oZKIjtpKrx59Ho=
+github.com/fsnotify/fsnotify v1.10.1/go.mod h1:TLheqan6HD6GBK6PrDWyDPBaEV8LspOxvPSjC+bVfgo=
+github.com/go-json-experiment/json v0.0.0-20260520185125-572e7c383686 h1:NZBJxCpbHS1gzS6xAmyxbJznosZIIPk9IB42v62UvKA=
+github.com/go-json-experiment/json v0.0.0-20260520185125-572e7c383686/go.mod h1:tphK2c80bpPhMOI4v6bIc2xWywPfbqi1Z06+RcrMkDg=
 github.com/go-logfmt/logfmt v0.6.1 h1:4hvbpePJKnIzH1B+8OR/JPbTx37NktoI9LE2QZBBkvE=
 github.com/go-logfmt/logfmt v0.6.1/go.mod h1:EV2pOAQoZaT1ZXZbqDl5hrymndi4SY9ED9/z6CO0XAk=
 github.com/go-logr/logr v1.2.2/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
@@ -167,14 +169,14 @@ github.com/golang/protobuf v1.5.4 h1:i7eJL8qZTpSEXOPTxNKhASYpMn+8e5Q6AdndVa1dWek
 github.com/golang/protobuf v1.5.4/go.mod h1:lnTiLA8Wa4RWRcIUkrtSVa5nRhsEGBg48fD6rSs7xps=
 github.com/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
 github.com/google/go-cmp v0.7.0/go.mod h1:pXiqmnSA92OHEEa9HXL2W4E7lf9JzCmGVUdgjX3N/iU=
-github.com/google/jsonschema-go v0.4.2 h1:tmrUohrwoLZZS/P3x7ex0WAVknEkBZM46iALbcqoRA8=
-github.com/google/jsonschema-go v0.4.2/go.mod h1:r5quNTdLOYEz95Ru18zA0ydNbBuYoo9tgaYcxEYhJVE=
+github.com/google/jsonschema-go v0.4.3 h1:/DBOLZTfDow7pe2GmaJNhltueGTtDKICi8V8p+DQPd0=
+github.com/google/jsonschema-go v0.4.3/go.mod h1:r5quNTdLOYEz95Ru18zA0ydNbBuYoo9tgaYcxEYhJVE=
 github.com/google/s2a-go v0.1.9 h1:LGD7gtMgezd8a/Xak7mEWL0PjoTQFvpRudN895yqKW0=
 github.com/google/s2a-go v0.1.9/go.mod h1:YA0Ei2ZQL3acow2O62kdp9UlnvMmU7kA6Eutn0dXayM=
 github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
 github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
-github.com/googleapis/enterprise-certificate-proxy v0.3.15 h1:xolVQTEXusUcAA5UgtyRLjelpFFHWlPQ4XfWGc7MBas=
-github.com/googleapis/enterprise-certificate-proxy v0.3.15/go.mod h1:vqVt9yG9480NtzREnTlmGSBmFrA+bzb0yl0TxoBQXOg=
+github.com/googleapis/enterprise-certificate-proxy v0.3.16 h1:F/VPrx0YPBdksZJQdCAp0WUsqnNmZpUZszzfYt0M5Dw=
+github.com/googleapis/enterprise-certificate-proxy v0.3.16/go.mod h1:9Yb0eAkH/Xqhvv3zbeKf/+wMJqCeocWc6KIhDvEAuYE=
 github.com/googleapis/gax-go/v2 v2.22.0 h1:PjIWBpgGIVKGoCXuiCoP64altEJCj3/Ei+kSU5vlZD4=
 github.com/googleapis/gax-go/v2 v2.22.0/go.mod h1:irWBbALSr0Sk3qlqb9SyJ1h68WjgeFuiOzI4Rqw5+aY=
 github.com/gorilla/websocket v1.5.3 h1:saDtZ6Pbx/0u+bgYQ3q96pZgCzfhKXGPqt7kZ72aNNg=
@@ -187,14 +189,14 @@ github.com/indaco/herald v0.13.0 h1:+xVG9Fx5NpuWhwku/9IlRL6I009NnX4VUGKvlZHTRxU=
 github.com/indaco/herald v0.13.0/go.mod h1:T5g1+XLYvpjouhzAGHnAHDCKizhESkoV6+QPZ3DhgWA=
 github.com/indaco/herald-md v0.3.0 h1:hN1cKyrexPPM9PeHBsKuaWvIizSi/iYvM9yzRgtdb8M=
 github.com/indaco/herald-md v0.3.0/go.mod h1:RUHVaDSG45ymJjKyxpDwBocLXrZo93FB4OeYMsw9B9s=
-github.com/kaptinlin/go-i18n v0.4.2 h1:52gGOx4ZwbLEiOyDMNA1ax2WktKlrKsmV6Ydf9Tw3/I=
-github.com/kaptinlin/go-i18n v0.4.2/go.mod h1:IACLIi+sHn3pGyryFMiqr2N1CJry4OKFD0MAEneEVQk=
-github.com/kaptinlin/jsonpointer v0.4.18 h1:EDUXT4WKpOKguU7oaFv6VaNatN7uHFe6dEYHX0+OFxs=
-github.com/kaptinlin/jsonpointer v0.4.18/go.mod h1:ndmfvrqrEDSbV3F7yGaOuDvr29WrxYU1aqkvef9L2do=
-github.com/kaptinlin/jsonschema v0.7.8 h1:aHv28bYtfLfUXYI/10Phb1nvVyLXNz1lmu73vtKmlOY=
-github.com/kaptinlin/jsonschema v0.7.8/go.mod h1:cz7SK0jTHdabKdQp+SwBKKmOeZ55txuNo72Jx9Sbb2w=
-github.com/kaptinlin/messageformat-go v0.5.2 h1:E+D5oQVRepHgyMiLWRHnPXYFbqBDI4Sek7/CTIAByj4=
-github.com/kaptinlin/messageformat-go v0.5.2/go.mod h1:NKjwS6e9u7DRhAK+vydjDDwJ7UbdHhYjk/yk2WPuZPs=
+github.com/kaptinlin/go-i18n v0.4.5 h1:9tIlo5A0RXth+yZJO2MG7Bhpu/X9PlzQnGz/qyYWNoY=
+github.com/kaptinlin/go-i18n v0.4.5/go.mod h1:mU/7BH4molY5lGZYBwBRKAaiJ70dWRHuqmQ0/pFLGno=
+github.com/kaptinlin/jsonpointer v0.4.25 h1:iJ197e8n+WwqaqBsa53FqG3rPJCg5oijyFXEXNWWC3E=
+github.com/kaptinlin/jsonpointer v0.4.25/go.mod h1:wVOBaXGGnP42YsMb6zev/3W5POTvspdNfh8DXzf8XS8=
+github.com/kaptinlin/jsonschema v0.7.13 h1:kahVXTy/rURL0XJjyQ9WELm59wEmXi6IY0TWswQEFvU=
+github.com/kaptinlin/jsonschema v0.7.13/go.mod h1:Uh0aUBusnhXDCEXJ2oimL/hx7YTo7F+sKniE+tM0ERc=
+github.com/kaptinlin/messageformat-go v0.6.0 h1:D6jiXFsKW4/JG2CMddv/F6Rev9KVbCRKEzzV5QOAcpc=
+github.com/kaptinlin/messageformat-go v0.6.0/go.mod h1:NKjwS6e9u7DRhAK+vydjDDwJ7UbdHhYjk/yk2WPuZPs=
 github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
 github.com/kr/pretty v0.3.1/go.mod h1:hoEshYVHaxMs3cyo3Yncou5ZscifuDolrwPKZanG3xk=
 github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
@@ -203,10 +205,10 @@ github.com/kylelemons/godebug v1.1.0 h1:RPNrshWIDI6G2gRW9EHilWtl7Z6Sb1BR0xunSBf0
 github.com/kylelemons/godebug v1.1.0/go.mod h1:9/0rRGxNHcop5bhtWyNeEfOS8JIWk580+fNqagV/RAw=
 github.com/lucasb-eyer/go-colorful v1.4.0 h1:UtrWVfLdarDgc44HcS7pYloGHJUjHV/4FwW4TvVgFr4=
 github.com/lucasb-eyer/go-colorful v1.4.0/go.mod h1:R4dSotOR9KMtayYi1e77YzuveK+i7ruzyGqttikkLy0=
-github.com/mark3labs/mcp-go v0.49.0 h1:7Ssx4d7/T86qnWoJIdye7wEEvUzv39UIbnZb/FqUZMY=
-github.com/mark3labs/mcp-go v0.49.0/go.mod h1:BflTAZAzXlrTpiO44gmjMu89n2FO56rJ9m31fp4zd5k=
-github.com/mattn/go-isatty v0.0.21 h1:xYae+lCNBP7QuW4PUnNG61ffM4hVIfm+zUzDuSzYLGs=
-github.com/mattn/go-isatty v0.0.21/go.mod h1:ZXfXG4SQHsB/w3ZeOYbR0PrPwLy+n6xiMrJlRFqopa4=
+github.com/mark3labs/mcp-go v0.54.1 h1:Ap/ptEB9FtWzFKM8NDsTA7QDxerQOC06eZigrTldVj0=
+github.com/mark3labs/mcp-go v0.54.1/go.mod h1:+8WclSK1ZUweCP3hvktSji8n8ABG/95QaEkeVE/Uwas=
+github.com/mattn/go-isatty v0.0.22 h1:j8l17JJ9i6VGPUFUYoTUKPSgKe/83EYU2zBC7YNKMw4=
+github.com/mattn/go-isatty v0.0.22/go.mod h1:ZXfXG4SQHsB/w3ZeOYbR0PrPwLy+n6xiMrJlRFqopa4=
 github.com/mattn/go-runewidth v0.0.23 h1:7ykA0T0jkPpzSvMS5i9uoNn2Xy3R383f9HDx3RybWcw=
 github.com/mattn/go-runewidth v0.0.23/go.mod h1:XBkDxAl56ILZc9knddidhrOlY5R/pDhgLpndooCuJAs=
 github.com/mitchellh/hashstructure/v2 v2.0.2 h1:vGKWl0YJqUNxE8d+h8f6NJLcCJrgbhC4NcD46KavDd4=
@@ -223,8 +225,8 @@ github.com/muesli/roff v0.1.0 h1:YD0lalCotmYuF5HhZliKWlIx7IEhiXeSfq7hNjFqGF8=
 github.com/muesli/roff v0.1.0/go.mod h1:pjAHQM9hdUUwm/krAfrLGgJkXJ+YuhtsfZ42kieB2Ig=
 github.com/muesli/termenv v0.16.0 h1:S5AlUN9dENB57rsbnkPyfdGuWIlkmzJjbFf0Tf5FWUc=
 github.com/muesli/termenv v0.16.0/go.mod h1:ZRfOIKPFDYQoDFF4Olj7/QJbW60Ol/kL1pU3VfY/Cnk=
-github.com/pelletier/go-toml/v2 v2.3.0 h1:k59bC/lIZREW0/iVaQR8nDHxVq8OVlIzYCOJf421CaM=
-github.com/pelletier/go-toml/v2 v2.3.0/go.mod h1:2gIqNv+qfxSVS7cM2xJQKtLSTLUE9V8t9Stt+h56mCY=
+github.com/pelletier/go-toml/v2 v2.3.1 h1:MYEvvGnQjeNkRF1qUuGolNtNExTDwct51yp7olPtrEc=
+github.com/pelletier/go-toml/v2 v2.3.1/go.mod h1:2gIqNv+qfxSVS7cM2xJQKtLSTLUE9V8t9Stt+h56mCY=
 github.com/pkg/browser v0.0.0-20240102092130-5ac0b6a4141c h1:+mdjkGKdHQG3305AYmdv1U2eRNDiU2ErMBj1gwrq8eQ=
 github.com/pkg/browser v0.0.0-20240102092130-5ac0b6a4141c/go.mod h1:7rwL4CYBLnjLxUqIJNnCWiEdr3bn6IUYi15bNlnbCCU=
 github.com/planetscale/vtprotobuf v0.6.1-0.20240319094008-0393e58bdf10 h1:GFCKgmp0tecUJ0sJuv4pzYCqS9+RGSn52M3FUwPs+uo=
@@ -238,6 +240,8 @@ github.com/rogpeppe/go-internal v1.14.1/go.mod h1:MaRKkUm5W0goXpeCfT7UZI6fk/L7L7
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/sagikazarmark/locafero v0.12.0 h1:/NQhBAkUb4+fH1jivKHWusDYFjMOOKU88eegjfxfHb4=
 github.com/sagikazarmark/locafero v0.12.0/go.mod h1:sZh36u/YSZ918v0Io+U9ogLYQJ9tLLBmM4eneO6WwsI=
+github.com/santhosh-tekuri/jsonschema/v6 v6.0.2 h1:KRzFb2m7YtdldCEkzs6KqmJw4nqEVZGK7IN2kJkjTuQ=
+github.com/santhosh-tekuri/jsonschema/v6 v6.0.2/go.mod h1:JXeL+ps8p7/KNMjDQk3TCwPpBy0wYklyWTfbkIzdIFU=
 github.com/spf13/afero v1.15.0 h1:b/YBCLWAJdFWJTN9cLhiXXcD7mzKn9Dm86dNnfyQw1I=
 github.com/spf13/afero v1.15.0/go.mod h1:NC2ByUVxtQs4b3sIUphxK0NioZnmxgyCrfzeuq8lxMg=
 github.com/spf13/cast v1.10.0 h1:h2x0u2shc1QuLHfxi+cTJvs30+ZAHOGRic8uyGTDWxY=
@@ -254,8 +258,8 @@ github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD
 github.com/subosito/gotenv v1.6.0 h1:9NlTDc1FTs4qu0DDq7AEtTPNw6SVm7uBMsUCUjABIf8=
 github.com/subosito/gotenv v1.6.0/go.mod h1:Dk4QP5c2W3ibzajGcXpNraDfq2IrhjMIvMSWPKKo0FU=
 github.com/tidwall/gjson v1.14.2/go.mod h1:/wbyibRr2FHMks5tjHJ5F8dMZh3AcwJEMf5vlfC0lxk=
-github.com/tidwall/gjson v1.18.0 h1:FIDeeyB800efLX89e5a8Y0BNH+LOngJyGrIWxG2FKQY=
-github.com/tidwall/gjson v1.18.0/go.mod h1:/wbyibRr2FHMks5tjHJ5F8dMZh3AcwJEMf5vlfC0lxk=
+github.com/tidwall/gjson v1.19.0 h1:xwxm7n691Uf3u5OFjzngavjGTh55KX5q/9w9xHW88JU=
+github.com/tidwall/gjson v1.19.0/go.mod h1:V37/opeE/JbLUOfH0QTXiNez2l0RUjYUhpT4szFQAfc=
 github.com/tidwall/match v1.1.1/go.mod h1:eRSPERbgtNPcGhD8UCthc6PmLEQXEWd3PRB5JTxsfmM=
 github.com/tidwall/match v1.2.0 h1:0pt8FlkOwjN2fPt4bIl4BoNxb98gGHN2ObFEDkrfZnM=
 github.com/tidwall/match v1.2.0/go.mod h1:eRSPERbgtNPcGhD8UCthc6PmLEQXEWd3PRB5JTxsfmM=
@@ -274,54 +278,54 @@ github.com/yuin/goldmark v1.8.2 h1:kEGpgqJXdgbkhcOgBxkC0X0PmoPG1ZyoZ117rDVp4zE=
 github.com/yuin/goldmark v1.8.2/go.mod h1:ip/1k0VRfGynBgxOz0yCqHrbZXhcjxyuS66Brc7iBKg=
 go.opentelemetry.io/auto/sdk v1.2.1 h1:jXsnJ4Lmnqd11kwkBV2LgLoFMZKizbCi5fNZ/ipaZ64=
 go.opentelemetry.io/auto/sdk v1.2.1/go.mod h1:KRTj+aOaElaLi+wW1kO/DZRXwkF4C5xPbEe3ZiIhN7Y=
-go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.68.0 h1:0Qx7VGBacMm9ZENQ7TnNObTYI4ShC+lHI16seduaxZo=
-go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.68.0/go.mod h1:Sje3i3MjSPKTSPvVWCaL8ugBzJwik3u4smCjUeuupqg=
-go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.68.0 h1:CqXxU8VOmDefoh0+ztfGaymYbhdB/tT3zs79QaZTNGY=
-go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.68.0/go.mod h1:BuhAPThV8PBHBvg8ZzZ/Ok3idOdhWIodywz2xEcRbJo=
-go.opentelemetry.io/otel v1.43.0 h1:mYIM03dnh5zfN7HautFE4ieIig9amkNANT+xcVxAj9I=
-go.opentelemetry.io/otel v1.43.0/go.mod h1:JuG+u74mvjvcm8vj8pI5XiHy1zDeoCS2LB1spIq7Ay0=
-go.opentelemetry.io/otel/metric v1.43.0 h1:d7638QeInOnuwOONPp4JAOGfbCEpYb+K6DVWvdxGzgM=
-go.opentelemetry.io/otel/metric v1.43.0/go.mod h1:RDnPtIxvqlgO8GRW18W6Z/4P462ldprJtfxHxyKd2PY=
-go.opentelemetry.io/otel/sdk v1.43.0 h1:pi5mE86i5rTeLXqoF/hhiBtUNcrAGHLKQdhg4h4V9Dg=
-go.opentelemetry.io/otel/sdk v1.43.0/go.mod h1:P+IkVU3iWukmiit/Yf9AWvpyRDlUeBaRg6Y+C58QHzg=
-go.opentelemetry.io/otel/sdk/metric v1.43.0 h1:S88dyqXjJkuBNLeMcVPRFXpRw2fuwdvfCGLEo89fDkw=
-go.opentelemetry.io/otel/sdk/metric v1.43.0/go.mod h1:C/RJtwSEJ5hzTiUz5pXF1kILHStzb9zFlIEe85bhj6A=
-go.opentelemetry.io/otel/trace v1.43.0 h1:BkNrHpup+4k4w+ZZ86CZoHHEkohws8AY+WTX09nk+3A=
-go.opentelemetry.io/otel/trace v1.43.0/go.mod h1:/QJhyVBUUswCphDVxq+8mld+AvhXZLhe+8WVFxiFff0=
+go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.69.0 h1:2yEATaop1/a1I4psnSLgWVPLWwCzkqWakgJy7xTDVy0=
+go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.69.0/go.mod h1:D7J12YRapIekYyPWgGPlA/23pRmpSEZC5xJC/TTLI9U=
+go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.69.0 h1:8tvICD4vSTOOsNrsI4Ljf6C+6UKvpTEH5XY3JMoyPoo=
+go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.69.0/go.mod h1:z9+yiacE0IHRqM4qFfkbt/JYlmYXgss8GY/jXoNuPJI=
+go.opentelemetry.io/otel v1.44.0 h1:JjwHmHpA4iZ3wBxluu2fbbE7j4kqlE8jXyAyPXH7HqU=
+go.opentelemetry.io/otel v1.44.0/go.mod h1:BMgjTHL9WPRlRjL2oZCBTL4whCGtXch2H4BhOPIAyYc=
+go.opentelemetry.io/otel/metric v1.44.0 h1:1w0gILTcHdr3YI+ixLyjemwrVnsMURbTZFrSYCdDdmc=
+go.opentelemetry.io/otel/metric v1.44.0/go.mod h1:8O7hanEPBNgEMmybD3s2VBKcgWOCsA6tzHBPODAiquo=
+go.opentelemetry.io/otel/sdk v1.44.0 h1:nHYwb9lK+fJPU/dnT6s7W7Z8itMWyqrnVfbheVYrZ58=
+go.opentelemetry.io/otel/sdk v1.44.0/go.mod h1:Osuydd3Se74nqjAKxid74N5eC+jfEqfTegHRnq58oK0=
+go.opentelemetry.io/otel/sdk/metric v1.44.0 h1:3LlKgI+VjbVsjNRFZJZAJ30WjXC5VkNRks6si09iEfI=
+go.opentelemetry.io/otel/sdk/metric v1.44.0/go.mod h1:5B5pMARnXxKhltooO4xUuCBorl65a4EpnTalObqOigA=
+go.opentelemetry.io/otel/trace v1.44.0 h1:jxF5CsGYCe74MCRx2X4g7WsY/VBKRqqpNvXlX/6gtIk=
+go.opentelemetry.io/otel/trace v1.44.0/go.mod h1:oLl1jrMQAVo6v3GAggN+1VH9VIz9iUSvW53sW1Q8PIE=
 go.yaml.in/yaml/v3 v3.0.4 h1:tfq32ie2Jv2UxXFdLJdh3jXuOzWiL1fo0bu/FbuKpbc=
 go.yaml.in/yaml/v3 v3.0.4/go.mod h1:DhzuOOF2ATzADvBadXxruRBLzYTpT36CKvDb3+aBEFg=
-golang.org/x/crypto v0.50.0 h1:zO47/JPrL6vsNkINmLoo/PH1gcxpls50DNogFvB5ZGI=
-golang.org/x/crypto v0.50.0/go.mod h1:3muZ7vA7PBCE6xgPX7nkzzjiUq87kRItoJQM1Yo8S+Q=
-golang.org/x/exp v0.0.0-20260410095643-746e56fc9e2f h1:W3F4c+6OLc6H2lb//N1q4WpJkhzJCK5J6kUi1NTVXfM=
-golang.org/x/exp v0.0.0-20260410095643-746e56fc9e2f/go.mod h1:J1xhfL/vlindoeF/aINzNzt2Bket5bjo9sdOYzOsU80=
-golang.org/x/net v0.53.0 h1:d+qAbo5L0orcWAr0a9JweQpjXF19LMXJE8Ey7hwOdUA=
-golang.org/x/net v0.53.0/go.mod h1:JvMuJH7rrdiCfbeHoo3fCQU24Lf5JJwT9W3sJFulfgs=
+golang.org/x/crypto v0.52.0 h1:RMs7fP2rXdep0CftQlK8Uf+kibLm7qkCcradZWYz988=
+golang.org/x/crypto v0.52.0/go.mod h1:1QgfPxDqh0T2M/elOJtp9RvuR95kVjir0e6/BvEmGbc=
+golang.org/x/exp v0.0.0-20260528193900-50dc527dd6c7 h1:cHpkPjp4TILjdZxz/O4ykwCpeS+dDqNuDGse4zgQDCk=
+golang.org/x/exp v0.0.0-20260528193900-50dc527dd6c7/go.mod h1:d2fgXJLVs4dYDHUk5lwMIfzRzSrWCfGZb0ZqeLa/Vcw=
+golang.org/x/net v0.55.0 h1:bcvxaJn3e1U6InsFWt1JUq1aSjnRxLzT2rtD2KfkDF8=
+golang.org/x/net v0.55.0/go.mod h1:L5U2KuzuOe1lY7Z+aWVIKK6qEeJXnXV9yzGA+WCHJww=
 golang.org/x/oauth2 v0.36.0 h1:peZ/1z27fi9hUOFCAZaHyrpWG5lwe0RJEEEeH0ThlIs=
 golang.org/x/oauth2 v0.36.0/go.mod h1:YDBUJMTkDnJS+A4BP4eZBjCqtokkg1hODuPjwiGPO7Q=
 golang.org/x/sync v0.20.0 h1:e0PTpb7pjO8GAtTs2dQ6jYa5BWYlMuX047Dco/pItO4=
 golang.org/x/sync v0.20.0/go.mod h1:9xrNwdLfx4jkKbNva9FpL6vEN7evnE43NNNJQ2LF3+0=
-golang.org/x/sys v0.43.0 h1:Rlag2XtaFTxp19wS8MXlJwTvoh8ArU6ezoyFsMyCTNI=
-golang.org/x/sys v0.43.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
-golang.org/x/term v0.42.0 h1:UiKe+zDFmJobeJ5ggPwOshJIVt6/Ft0rcfrXZDLWAWY=
-golang.org/x/term v0.42.0/go.mod h1:Dq/D+snpsbazcBG5+F9Q1n2rXV8Ma+71xEjTRufARgY=
-golang.org/x/text v0.36.0 h1:JfKh3XmcRPqZPKevfXVpI1wXPTqbkE5f7JA92a55Yxg=
-golang.org/x/text v0.36.0/go.mod h1:NIdBknypM8iqVmPiuco0Dh6P5Jcdk8lJL0CUebqK164=
+golang.org/x/sys v0.45.0 h1:dO4czNzziLiiXplLQgBCEpCvXQ3dnkn0SdaZSYdQ+FY=
+golang.org/x/sys v0.45.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
+golang.org/x/term v0.43.0 h1:S4RLU2sB31O/NCl+zFN9Aru9A/Cq2aqKpTZJ6B+DwT4=
+golang.org/x/term v0.43.0/go.mod h1:lrhlHNdQJHO+1qVYiHfFKVuVioJIheAc3fBSMFYEIsk=
+golang.org/x/text v0.37.0 h1:Cqjiwd9eSg8e0QAkyCaQTNHFIIzWtidPahFWR83rTrc=
+golang.org/x/text v0.37.0/go.mod h1:a5sjxXGs9hsn/AJVwuElvCAo9v8QYLzvavO5z2PiM38=
 golang.org/x/time v0.15.0 h1:bbrp8t3bGUeFOx08pvsMYRTCVSMk89u4tKbNOZbp88U=
 golang.org/x/time v0.15.0/go.mod h1:Y4YMaQmXwGQZoFaVFk4YpCt4FLQMYKZe9oeV/f4MSno=
 gonum.org/v1/gonum v0.17.0 h1:VbpOemQlsSMrYmn7T2OUvQ4dqxQXU+ouZFQsZOx50z4=
 gonum.org/v1/gonum v0.17.0/go.mod h1:El3tOrEuMpv2UdMrbNlKEh9vd86bmQ6vqIcDwxEOc1E=
-google.golang.org/api v0.276.0 h1:nVArUtfLEihtW+b0DdcqRGK1xoEm2+ltAihyztq7MKY=
-google.golang.org/api v0.276.0/go.mod h1:Fnag/EWUPIcJXuIkP1pjoTgS5vdxlk3eeemL7Do6bvw=
-google.golang.org/genai v1.54.0 h1:ZQCa70WMTJDI11FdqWCzGvZ5PanpcpfoO6jl/lrSnGU=
-google.golang.org/genai v1.54.0/go.mod h1:A3kkl0nyBjyFlNjgxIwKq70julKbIxpSxqKO5gw/gmk=
-google.golang.org/genproto v0.0.0-20260406210006-6f92a3bedf2d h1:N1Ec54vZnIPd7MnxRiYLW+oY4fDR4BOS/LrssdD9+ek=
-google.golang.org/genproto v0.0.0-20260406210006-6f92a3bedf2d/go.mod h1:c2hJ1grtnH0xUiEKGDGkjGNTJ1Hy2LrblyKOHF0sqRM=
-google.golang.org/genproto/googleapis/api v0.0.0-20260406210006-6f92a3bedf2d h1:/aDRtSZJjyLQzm75d+a1wOJaqyKBMvIAfeQmoa3ORiI=
-google.golang.org/genproto/googleapis/api v0.0.0-20260406210006-6f92a3bedf2d/go.mod h1:etfGUgejTiadZAUaEP14NP97xi1RGeawqkjDARA/UOs=
-google.golang.org/genproto/googleapis/rpc v0.0.0-20260420184626-e10c466a9529 h1:XF8+t6QQiS0o9ArVan/HW8Q7cycNPGsJf6GA2nXxYAg=
-google.golang.org/genproto/googleapis/rpc v0.0.0-20260420184626-e10c466a9529/go.mod h1:4Hqkh8ycfw05ld/3BWL7rJOSfebL2Q+DVDeRgYgxUU8=
-google.golang.org/grpc v1.80.0 h1:Xr6m2WmWZLETvUNvIUmeD5OAagMw3FiKmMlTdViWsHM=
-google.golang.org/grpc v1.80.0/go.mod h1:ho/dLnxwi3EDJA4Zghp7k2Ec1+c2jqup0bFkw07bwF4=
+google.golang.org/api v0.282.0 h1:WmJiSVqUnKqJCpJOx7YADbXaC+9DDsnGSfllFSj7R2I=
+google.golang.org/api v0.282.0/go.mod h1:6Wssta4c5n9qHq5CBhmlai5h/PUa1djdDAIhYEHyvcM=
+google.golang.org/genai v1.58.0 h1:MNA3ZkRyr7MnRwZ9RNZ60p4+UMKV3yYRw6pyHq4pp0U=
+google.golang.org/genai v1.58.0/go.mod h1:A3kkl0nyBjyFlNjgxIwKq70julKbIxpSxqKO5gw/gmk=
+google.golang.org/genproto v0.0.0-20260504160031-60b97b32f348 h1:JjVGDZYWkJWZcxveJGzfkXC5myDVWAd4dZdgbzrDUv8=
+google.golang.org/genproto v0.0.0-20260504160031-60b97b32f348/go.mod h1:95PqD4xM+AdOcBGsmgfaofXsiA37uXDtDufVbntT3TU=
+google.golang.org/genproto/googleapis/api v0.0.0-20260504160031-60b97b32f348 h1:U8orV30l6KpDsi9dxU0CoJZGbjS8EEpw+6ba+XwGPQA=
+google.golang.org/genproto/googleapis/api v0.0.0-20260504160031-60b97b32f348/go.mod h1:Yzdzr5OOZFgSsEV2D/Xi9NL3bszpXFAg0hFJiRohcD8=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20260526163538-3dc84a4a5aaa h1:mZHHdPZl0dbGHCflZgAq/Q468DWVFcU2whhB2KAo8fk=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20260526163538-3dc84a4a5aaa/go.mod h1:4Hqkh8ycfw05ld/3BWL7rJOSfebL2Q+DVDeRgYgxUU8=
+google.golang.org/grpc v1.81.1 h1:VnnIIZ88UzOOKLukQi+ImGz8O1Wdp8nAGGnvOfEIWQQ=
+google.golang.org/grpc v1.81.1/go.mod h1:xGH9GfzOyMTGIOXBJmXt+BX/V0kcdQbdcuwQ/zNw42I=
 google.golang.org/protobuf v1.36.11 h1:fV6ZwhNocDyBLK0dj+fg8ektcVegBBuEolpbTQyBNVE=
 google.golang.org/protobuf v1.36.11/go.mod h1:HTf+CrKn2C3g5S8VImy6tdcUvCska2kB7j23XfzDpco=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=

internal/acpserver/agent.go

@@ -185,6 +185,26 @@ func (a *Agent) ListSessions(_ context.Context, _ acp.ListSessionsRequest) (acp.
 	}, nil
 }
 
+// CloseSession cancels any ongoing work for the session and frees its resources.
+func (a *Agent) CloseSession(_ context.Context, params acp.CloseSessionRequest) (acp.CloseSessionResponse, error) {
+	sessionID := string(params.SessionId)
+	sess, ok := a.registry.get(sessionID)
+	if !ok {
+		return acp.CloseSessionResponse{}, nil
+	}
+
+	log.Debug("acp: close session", "session", sessionID)
+	sess.cancelPrompt()
+	a.registry.remove(sessionID)
+	return acp.CloseSessionResponse{}, nil
+}
+
+// ResumeSession is not supported — Kit doesn't persist sessions across
+// restarts in ACP mode. Clients should use NewSession instead.
+func (a *Agent) ResumeSession(_ context.Context, _ acp.ResumeSessionRequest) (acp.ResumeSessionResponse, error) {
+	return acp.ResumeSessionResponse{}, fmt.Errorf("resume session not supported")
+}
+
 // SetSessionConfigOption handles session configuration changes. Currently
 // supports the "model" config option to change the active model for a session.
 func (a *Agent) SetSessionConfigOption(ctx context.Context, params acp.SetSessionConfigOptionRequest) (acp.SetSessionConfigOptionResponse, error) {

internal/acpserver/session.go

@@ -8,6 +8,7 @@ import (
 
 	"github.com/charmbracelet/log"
 
+	"github.com/mark3labs/kit/internal/extbridge"
 	"github.com/mark3labs/kit/internal/extensions"
 	kit "github.com/mark3labs/kit/pkg/kit"
 )
@@ -152,38 +153,7 @@ func (r *sessionRegistry) create(ctx context.Context, cwd string) (*acpSession,
 				return kitInstance.ExecuteCompletion(context.Background(), req)
 			},
 			SpawnSubagent: func(config extensions.SubagentConfig) (*extensions.SubagentHandle, *extensions.SubagentResult, error) {
-				sdkCfg := kit.SubagentConfig{
-					Prompt:       config.Prompt,
-					Model:        config.Model,
-					SystemPrompt: config.SystemPrompt,
-					Timeout:      config.Timeout,
-					NoSession:    config.NoSession,
-				}
-				if config.OnEvent != nil {
-					sdkCfg.OnEvent = func(e kit.Event) {
-						se := sdkEventToSubagentEvent(e)
-						if se.Type != "" {
-							config.OnEvent(se)
-						}
-					}
-				}
-				result, err := kitInstance.Subagent(context.Background(), sdkCfg)
-				if result == nil {
-					return nil, &extensions.SubagentResult{Error: err}, err
-				}
-				extResult := &extensions.SubagentResult{
-					Response:  result.Response,
-					Error:     err,
-					SessionID: result.SessionID,
-					Elapsed:   result.Elapsed,
-				}
-				if result.Usage != nil {
-					extResult.Usage = &extensions.SubagentUsage{
-						InputTokens:  result.Usage.InputTokens,
-						OutputTokens: result.Usage.OutputTokens,
-					}
-				}
-				return nil, extResult, err
+				return extbridge.SpawnSubagent(context.Background(), kitInstance, config)
 			},
 
 			// Render — fall back to logging.
@@ -232,6 +202,20 @@ func (r *sessionRegistry) closeAll() {
 	}
 }
 
+// remove closes and removes a single session by ID.
+func (r *sessionRegistry) remove(sessionID string) {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	sess, ok := r.sessions[sessionID]
+	if !ok {
+		return
+	}
+	if sess.kit != nil {
+		_ = sess.kit.Close()
+	}
+	delete(r.sessions, sessionID)
+}
+
 // cancelPrompt cancels the current prompt for a session, if any.
 func (s *acpSession) cancelPrompt() {
 	s.cancelMu.Lock()
@@ -255,40 +239,3 @@ func (s *acpSession) clearCancel() {
 	defer s.cancelMu.Unlock()
 	s.cancelFn = nil
 }
-
-// sdkEventToSubagentEvent converts an SDK event to an extension SubagentEvent.
-func sdkEventToSubagentEvent(e kit.Event) extensions.SubagentEvent {
-	switch ev := e.(type) {
-	case kit.MessageUpdateEvent:
-		return extensions.SubagentEvent{Type: "text", Content: ev.Chunk}
-	case kit.ReasoningDeltaEvent:
-		return extensions.SubagentEvent{Type: "reasoning", Content: ev.Delta}
-	case kit.ToolCallEvent:
-		return extensions.SubagentEvent{
-			Type: "tool_call", ToolCallID: ev.ToolCallID,
-			ToolName: ev.ToolName, ToolKind: ev.ToolKind, ToolArgs: ev.ToolArgs,
-		}
-	case kit.ToolExecutionStartEvent:
-		return extensions.SubagentEvent{
-			Type: "tool_execution_start", ToolCallID: ev.ToolCallID,
-			ToolName: ev.ToolName, ToolKind: ev.ToolKind,
-		}
-	case kit.ToolExecutionEndEvent:
-		return extensions.SubagentEvent{
-			Type: "tool_execution_end", ToolCallID: ev.ToolCallID,
-			ToolName: ev.ToolName, ToolKind: ev.ToolKind,
-		}
-	case kit.ToolResultEvent:
-		return extensions.SubagentEvent{
-			Type: "tool_result", ToolCallID: ev.ToolCallID,
-			ToolName: ev.ToolName, ToolKind: ev.ToolKind,
-			ToolResult: ev.Result, IsError: ev.IsError,
-		}
-	case kit.TurnStartEvent:
-		return extensions.SubagentEvent{Type: "turn_start"}
-	case kit.TurnEndEvent:
-		return extensions.SubagentEvent{Type: "turn_end"}
-	default:
-		return extensions.SubagentEvent{}
-	}
-}

internal/agent/agent.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"io"
 	"strings"
+	"sync"
 	"time"
 
 	"charm.land/fantasy"
@@ -59,6 +60,11 @@ type AgentConfig struct {
 	// loading (successfully or with error). The callback receives the server
 	// name, tool count, and any error. Called from the background goroutine.
 	OnMCPServerLoaded func(serverName string, toolCount int, err error)
+
+	// MCPTaskConfig configures task-augmented tools/call execution. The
+	// zero value preserves historical synchronous-only behaviour for any
+	// server that didn't advertise task support during initialize.
+	MCPTaskConfig tools.MCPTaskConfig
 }
 
 // ToolCallHandler is a function type for handling tool calls as they happen.
@@ -231,11 +237,21 @@ type Agent struct {
 	authHandler       tools.MCPAuthHandler
 	tokenStoreFactory tools.TokenStoreFactory
 
+	// mcpTaskConfig is stored from AgentConfig so AddMCPServer() can
+	// propagate it to a lazily-created MCPToolManager.
+	mcpTaskConfig tools.MCPTaskConfig
+
 	// mcpReady is closed when background MCP tool loading completes (success
 	// or failure). nil when no MCP servers are configured.
 	mcpReady chan struct{}
 	// mcpErr holds any error from background MCP loading.
 	mcpErr error
+
+	// promptMu serializes runtime updates to systemPrompt and the
+	// accompanying fantasy agent rebuild so concurrent SetSystemPrompt
+	// callers (e.g. Kit.applyComposedSystemPrompt invoked from multiple
+	// goroutines) don't race on a.systemPrompt / a.fantasyAgent.
+	promptMu sync.Mutex
 }
 
 // GenerateWithLoopResult contains the result and conversation history from an agent interaction.
@@ -329,6 +345,7 @@ func NewAgent(ctx context.Context, agentConfig *AgentConfig) (*Agent, error) {
 		modelConfig:         agentConfig.ModelConfig,
 		authHandler:         agentConfig.AuthHandler,
 		tokenStoreFactory:   agentConfig.TokenStoreFactory,
+		mcpTaskConfig:       agentConfig.MCPTaskConfig,
 	}
 
 	// Start MCP tool loading in the background if servers are configured.
@@ -348,6 +365,8 @@ func NewAgent(ctx context.Context, agentConfig *AgentConfig) (*Agent, error) {
 		if agentConfig.OnMCPServerLoaded != nil {
 			toolManager.SetOnServerLoaded(agentConfig.OnMCPServerLoaded)
 		}
+		// Apply task-augmented tool execution config (zero value = no-op).
+		toolManager.SetTaskConfig(agentConfig.MCPTaskConfig)
 		a.toolManager = toolManager
 		a.mcpReady = make(chan struct{})
 
@@ -573,8 +592,13 @@ func (a *Agent) GenerateWithCallbacks(ctx context.Context, messages []fantasy.Me
 	// This avoids type conflicts with provider-level options.
 	history = applyCacheControlToMessages(history)
 
-	// Track current tool call args for callbacks
-	var currentToolArgs string
+	// Track tool call args per-ToolCallID so parallel tool calls in a single
+	// step don't clobber each other. Without this, OnToolResult callbacks would
+	// all see the args of the last OnToolCall in the step. The mutex guards
+	// against the possibility that the underlying streaming layer dispatches
+	// callbacks from multiple goroutines.
+	toolCallArgs := make(map[string]string)
+	var toolCallArgsMu sync.Mutex
 
 	// Use the streaming path when streaming is enabled OR when any callbacks are
 	// provided. The agent only exposes tool/step callbacks on AgentStreamCall, so
@@ -761,7 +785,9 @@ func (a *Agent) GenerateWithCallbacks(ctx context.Context, messages []fantasy.Me
 				if ctx.Err() != nil {
 					return ctx.Err()
 				}
-				currentToolArgs = tc.Input
+				toolCallArgsMu.Lock()
+				toolCallArgs[tc.ToolCallID] = tc.Input
+				toolCallArgsMu.Unlock()
 
 				// Notify about the tool call
 				if cb.OnToolCall != nil {
@@ -781,15 +807,22 @@ func (a *Agent) GenerateWithCallbacks(ctx context.Context, messages []fantasy.Me
 				if ctx.Err() != nil {
 					return ctx.Err()
 				}
+				// Look up the args recorded for this specific tool call. Delete
+				// the entry so the map doesn't accumulate across steps.
+				toolCallArgsMu.Lock()
+				args := toolCallArgs[tr.ToolCallID]
+				delete(toolCallArgs, tr.ToolCallID)
+				toolCallArgsMu.Unlock()
+
 				// Notify tool execution finished
 				if cb.OnToolExecution != nil {
-					cb.OnToolExecution(tr.ToolCallID, tr.ToolName, currentToolArgs, false)
+					cb.OnToolExecution(tr.ToolCallID, tr.ToolName, args, false)
 				}
 
 				if cb.OnToolResult != nil {
 					// Extract result text and error status
 					resultText, isError := extractToolResultText(tr)
-					cb.OnToolResult(tr.ToolCallID, tr.ToolName, currentToolArgs, resultText, tr.ClientMetadata, isError)
+					cb.OnToolResult(tr.ToolCallID, tr.ToolName, args, resultText, tr.ClientMetadata, isError)
 				}
 
 				return nil
@@ -1134,6 +1167,7 @@ func (a *Agent) AddMCPServer(ctx context.Context, name string, cfg config.MCPSer
 		if a.tokenStoreFactory != nil {
 			a.toolManager.SetTokenStoreFactory(a.tokenStoreFactory)
 		}
+		a.toolManager.SetTaskConfig(a.mcpTaskConfig)
 		a.toolManager.SetOnToolsChanged(func() {
 			a.rebuildFantasyAgent()
 		})
@@ -1290,6 +1324,24 @@ func (a *Agent) GetModel() fantasy.LanguageModel {
 	return a.model
 }
 
+// SetSystemPrompt updates the agent's system prompt and rebuilds the underlying
+// fantasy agent so subsequent turns use the new prompt. Safe to call while the
+// agent is idle; if invoked during an in-flight turn the new prompt takes
+// effect on the next LLM call.
+func (a *Agent) SetSystemPrompt(prompt string) {
+	a.promptMu.Lock()
+	defer a.promptMu.Unlock()
+	a.systemPrompt = prompt
+	a.rebuildFantasyAgent()
+}
+
+// GetSystemPrompt returns the agent's current system prompt.
+func (a *Agent) GetSystemPrompt() string {
+	a.promptMu.Lock()
+	defer a.promptMu.Unlock()
+	return a.systemPrompt
+}
+
 // GetMaxTokens returns the effective max output tokens the agent currently
 // sends to the LLM provider, after per-model defaults, right-sizing, and any
 // Anthropic thinking-budget adjustments. Returns 0 when no ModelConfig is

internal/agent/agent_parallel_tool_args_test.go

@@ -0,0 +1,109 @@
+package agent
+
+import (
+	"context"
+	"sync"
+	"testing"
+
+	"charm.land/fantasy"
+)
+
+// fakeParallelAgent simulates a provider that emits two parallel tool_use
+// blocks in a single step. It invokes the streaming callbacks in the order:
+//
+//	OnToolCall(A) -> OnToolCall(B) -> OnToolResult(A) -> OnToolResult(B)
+//
+// Before the fix in #33 the agent-layer wrapper recorded a single
+// `currentToolArgs` variable that was clobbered by the second OnToolCall, so
+// both OnToolResult callbacks received B's args instead of their own.
+type fakeParallelAgent struct {
+	calls   []fantasy.ToolCallContent
+	results []fantasy.ToolResultContent
+}
+
+func (f *fakeParallelAgent) Generate(_ context.Context, _ fantasy.AgentCall) (*fantasy.AgentResult, error) {
+	return &fantasy.AgentResult{}, nil
+}
+
+func (f *fakeParallelAgent) Stream(_ context.Context, opts fantasy.AgentStreamCall) (*fantasy.AgentResult, error) {
+	for _, tc := range f.calls {
+		if opts.OnToolCall != nil {
+			if err := opts.OnToolCall(tc); err != nil {
+				return nil, err
+			}
+		}
+	}
+	for _, tr := range f.results {
+		if opts.OnToolResult != nil {
+			if err := opts.OnToolResult(tr); err != nil {
+				return nil, err
+			}
+		}
+	}
+	return &fantasy.AgentResult{}, nil
+}
+
+// TestGenerateWithCallbacks_ParallelToolArgs is the regression test for #33.
+// It drives the streaming-callback wiring inside GenerateWithCallbacks with a
+// fake fantasy.Agent that emits two parallel tool calls before either result.
+// Each OnToolResult must receive the args of its own tool call (matched by
+// ToolCallID), not the args of the last OnToolCall in the step.
+func TestGenerateWithCallbacks_ParallelToolArgs(t *testing.T) {
+	t.Parallel()
+
+	argsA := `{"name":"scheduled_jobs"}`
+	argsB := `{"name":"gmail_trigger"}`
+
+	fake := &fakeParallelAgent{
+		calls: []fantasy.ToolCallContent{
+			{ToolCallID: "kit-A", ToolName: "load_skill", Input: argsA},
+			{ToolCallID: "kit-B", ToolName: "load_skill", Input: argsB},
+		},
+		results: []fantasy.ToolResultContent{
+			{ToolCallID: "kit-A", ToolName: "load_skill", Result: fantasy.ToolResultOutputContentText{Text: "ok-A"}},
+			{ToolCallID: "kit-B", ToolName: "load_skill", Result: fantasy.ToolResultOutputContentText{Text: "ok-B"}},
+		},
+	}
+
+	a := &Agent{
+		fantasyAgent:     fake,
+		streamingEnabled: false, // exercise the "hasCallbacks" branch
+	}
+
+	var mu sync.Mutex
+	resultArgs := map[string]string{}
+	executionArgs := map[string]string{} // captured when running == false
+
+	cb := GenerateCallbacks{
+		OnToolExecution: func(id, _, args string, running bool) {
+			if running {
+				return
+			}
+			mu.Lock()
+			defer mu.Unlock()
+			executionArgs[id] = args
+		},
+		OnToolResult: func(id, _, args, _, _ string, _ bool) {
+			mu.Lock()
+			defer mu.Unlock()
+			resultArgs[id] = args
+		},
+	}
+
+	if _, err := a.GenerateWithCallbacks(context.Background(), nil, cb); err != nil {
+		t.Fatalf("GenerateWithCallbacks returned error: %v", err)
+	}
+
+	if got, want := resultArgs["kit-A"], argsA; got != want {
+		t.Errorf("OnToolResult for kit-A: args = %q, want %q", got, want)
+	}
+	if got, want := resultArgs["kit-B"], argsB; got != want {
+		t.Errorf("OnToolResult for kit-B: args = %q, want %q", got, want)
+	}
+	if got, want := executionArgs["kit-A"], argsA; got != want {
+		t.Errorf("OnToolExecution(finish) for kit-A: args = %q, want %q", got, want)
+	}
+	if got, want := executionArgs["kit-B"], argsB; got != want {
+		t.Errorf("OnToolExecution(finish) for kit-B: args = %q, want %q", got, want)
+	}
+}

internal/agent/factory.go

@@ -56,6 +56,8 @@ type AgentCreationOptions struct {
 	// OnMCPServerLoaded, if non-nil, is called when each MCP server finishes
 	// loading (successfully or with error). Called from the background goroutine.
 	OnMCPServerLoaded func(serverName string, toolCount int, err error)
+	// MCPTaskConfig configures task-augmented tools/call execution.
+	MCPTaskConfig tools.MCPTaskConfig
 }
 
 // CreateAgent creates an agent with optional spinner for Ollama models.
@@ -76,6 +78,7 @@ func CreateAgent(ctx context.Context, opts *AgentCreationOptions) (*Agent, error
 		ToolWrapper:       opts.ToolWrapper,
 		ExtraTools:        opts.ExtraTools,
 		OnMCPServerLoaded: opts.OnMCPServerLoaded,
+		MCPTaskConfig:     opts.MCPTaskConfig,
 	}
 
 	var agent *Agent

internal/agent/mcp_adapter.go

@@ -9,12 +9,19 @@ import (
 	"github.com/mark3labs/kit/internal/tools"
 )
 
+// mcpExecutor is the subset of *tools.MCPToolManager that the adapter
+// actually uses. Extracted as an interface so the adapter is unit-testable
+// without constructing a full manager + connection pool.
+type mcpExecutor interface {
+	ExecuteTool(ctx context.Context, prefixedName, inputJSON string) (*tools.MCPToolResult, error)
+}
+
 // mcpAgentTool adapts an tools.MCPTool to the fantasy.AgentTool interface.
 // This keeps the fantasy dependency confined to the agent layer — the tools
 // package is a pure MCP client library with no LLM framework dependency.
 type mcpAgentTool struct {
 	tool            tools.MCPTool
-	manager         *tools.MCPToolManager
+	exec            mcpExecutor
 	providerOptions fantasy.ProviderOptions
 }
 
@@ -29,10 +36,26 @@ func (t *mcpAgentTool) Info() fantasy.ToolInfo {
 }
 
 // Run executes the MCP tool by delegating to the MCPToolManager.
+//
+// MCP-side failures (JSON-RPC protocol errors, transport failures, schema
+// validation rejections from the server) are surfaced to the model as soft
+// tool errors rather than escalated to a critical agent error. This matches
+// the contract that native Kit tools follow via kit.ErrorResult(...) and
+// lets the model self-correct (e.g. retry with a fixed argument shape) or
+// give up gracefully rather than aborting the turn mid-run.
+//
+// Context cancellation is the one exception: if the caller cancelled the
+// context the turn was aborted intentionally, so we propagate the ctx error
+// to let the agent loop unwind cleanly.
 func (t *mcpAgentTool) Run(ctx context.Context, call fantasy.ToolCall) (fantasy.ToolResponse, error) {
-	result, err := t.manager.ExecuteTool(ctx, t.tool.Name, call.Input)
+	result, err := t.exec.ExecuteTool(ctx, t.tool.Name, call.Input)
 	if err != nil {
-		return fantasy.ToolResponse{}, fmt.Errorf("mcp tool execution failed: %w", err)
+		if ctxErr := ctx.Err(); ctxErr != nil {
+			return fantasy.ToolResponse{}, ctxErr
+		}
+		return fantasy.NewTextErrorResponse(
+			fmt.Sprintf("MCP tool %q failed: %s", t.tool.Name, err.Error()),
+		), nil
 	}
 
 	if result.IsError {
@@ -57,8 +80,8 @@ func mcpToolsToAgentTools(mcpTools []tools.MCPTool, manager *tools.MCPToolManage
 	agentTools := make([]fantasy.AgentTool, len(mcpTools))
 	for i, t := range mcpTools {
 		agentTools[i] = &mcpAgentTool{
-			tool:    t,
-			manager: manager,
+			tool: t,
+			exec: manager,
 		}
 	}
 	return agentTools

internal/agent/mcp_adapter_test.go

@@ -0,0 +1,158 @@
+package agent
+
+import (
+	"context"
+	"errors"
+	"strings"
+	"testing"
+	"time"
+
+	"charm.land/fantasy"
+
+	"github.com/mark3labs/kit/internal/tools"
+)
+
+// stubExecutor lets each test script the (result, err) pair returned by
+// ExecuteTool. The adapter holds an mcpExecutor interface, so this is the
+// only seam the tests need.
+type stubExecutor struct {
+	result *tools.MCPToolResult
+	err    error
+	// called records the last invocation for assertion.
+	called bool
+	name   string
+	input  string
+}
+
+func (s *stubExecutor) ExecuteTool(_ context.Context, prefixedName, inputJSON string) (*tools.MCPToolResult, error) {
+	s.called = true
+	s.name = prefixedName
+	s.input = inputJSON
+	return s.result, s.err
+}
+
+func newMCPAgentTool(exec mcpExecutor, name string) *mcpAgentTool {
+	return &mcpAgentTool{
+		tool: tools.MCPTool{Name: name},
+		exec: exec,
+	}
+}
+
+// Manager-side Go errors (JSON-RPC protocol errors, transport failures,
+// schema validation rejections from the MCP server) must be surfaced to
+// the model as soft tool errors so the agent loop can keep going. Aborting
+// the turn would discard all prior tool results — see issue #N.
+func TestMCPAgentTool_RPCErrorBecomesSoftError(t *testing.T) {
+	exec := &stubExecutor{
+		err: errors.New("MCP error -32602: Invalid params: missing field \"task\""),
+	}
+	tool := newMCPAgentTool(exec, "pubmed__search")
+
+	resp, err := tool.Run(context.Background(), fantasy.ToolCall{
+		ID:    "call-1",
+		Name:  "pubmed__search",
+		Input: `{"query":"foo"}`,
+	})
+
+	if err != nil {
+		t.Fatalf("expected nil error (soft), got %v", err)
+	}
+	if !resp.IsError {
+		t.Fatalf("expected IsError=true, got false")
+	}
+	if !strings.Contains(resp.Content, "pubmed__search") {
+		t.Errorf("expected tool name in error content, got %q", resp.Content)
+	}
+	if !strings.Contains(resp.Content, "-32602") {
+		t.Errorf("expected underlying error text in content, got %q", resp.Content)
+	}
+}
+
+// Context cancellation is the one error that must remain critical: it
+// means the caller intentionally aborted, and the agent loop needs to
+// unwind cleanly rather than burning more steps.
+func TestMCPAgentTool_CtxCancelStaysCritical(t *testing.T) {
+	exec := &stubExecutor{
+		// Real managers typically return ctx.Err() (or a wrapper) when the
+		// context is cancelled mid-call.
+		err: context.Canceled,
+	}
+	tool := newMCPAgentTool(exec, "slow__tool")
+
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+
+	resp, err := tool.Run(ctx, fantasy.ToolCall{Name: "slow__tool"})
+
+	if !errors.Is(err, context.Canceled) {
+		t.Fatalf("expected context.Canceled, got %v", err)
+	}
+	if resp.IsError || resp.Content != "" {
+		t.Errorf("expected empty response on critical error, got IsError=%v Content=%q", resp.IsError, resp.Content)
+	}
+}
+
+// Deadline-exceeded behaves the same as cancellation: ctx.Err() is
+// non-nil, so the adapter must propagate the critical error rather than
+// converting the executor's error into a soft response.
+func TestMCPAgentTool_CtxDeadlineStaysCritical(t *testing.T) {
+	exec := &stubExecutor{err: context.DeadlineExceeded}
+	tool := newMCPAgentTool(exec, "slow__tool")
+
+	ctx, cancel := context.WithDeadline(context.Background(), time.Now().Add(-time.Second))
+	defer cancel()
+
+	resp, err := tool.Run(ctx, fantasy.ToolCall{Name: "slow__tool"})
+	if !errors.Is(err, context.DeadlineExceeded) {
+		t.Fatalf("expected context.DeadlineExceeded, got %v", err)
+	}
+	if resp.IsError || resp.Content != "" {
+		t.Errorf("expected empty response on critical error, got IsError=%v Content=%q", resp.IsError, resp.Content)
+	}
+}
+
+// Server-side soft errors (CallToolResult{ isError: true }) must continue
+// to flow through as soft errors — this was the existing behavior and
+// must not regress.
+func TestMCPAgentTool_ServerIsErrorRemainsSoftError(t *testing.T) {
+	exec := &stubExecutor{
+		result: &tools.MCPToolResult{
+			IsError: true,
+			Content: "search service is rate limited; try again in 30s",
+		},
+	}
+	tool := newMCPAgentTool(exec, "pubmed__search")
+
+	resp, err := tool.Run(context.Background(), fantasy.ToolCall{Name: "pubmed__search"})
+	if err != nil {
+		t.Fatalf("expected nil error, got %v", err)
+	}
+	if !resp.IsError {
+		t.Fatalf("expected IsError=true, got false")
+	}
+	if resp.Content != "search service is rate limited; try again in 30s" {
+		t.Errorf("expected pass-through content, got %q", resp.Content)
+	}
+}
+
+// Happy path: ordinary successful tool result is passed through unchanged.
+func TestMCPAgentTool_SuccessIsPassthrough(t *testing.T) {
+	exec := &stubExecutor{
+		result: &tools.MCPToolResult{
+			IsError: false,
+			Content: `{"hits":3}`,
+		},
+	}
+	tool := newMCPAgentTool(exec, "pubmed__search")
+
+	resp, err := tool.Run(context.Background(), fantasy.ToolCall{Name: "pubmed__search"})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if resp.IsError {
+		t.Fatalf("expected IsError=false")
+	}
+	if resp.Content != `{"hits":3}` {
+		t.Errorf("expected pass-through content, got %q", resp.Content)
+	}
+}

internal/app/app.go

@@ -70,14 +70,24 @@ type App struct {
 	rootCtx    context.Context
 	rootCancel context.CancelFunc
 
-	// widgetUpdatePending is set to true when a WidgetUpdateEvent has been
-	// sent to the TUI but not yet consumed by its event loop. While the flag
-	// is set, subsequent NotifyWidgetUpdate calls are coalesced (dropped) to
-	// prevent fast extension tickers from flooding the BubbleTea mailbox with
-	// redundant re-render triggers. The flag is cleared after a short debounce
-	// (~1 frame) so new updates are always let through once the TUI has had a
-	// chance to process the pending event.
-	widgetUpdatePending atomic.Bool
+	// widgetUpdatePending is set to true while a WidgetUpdateEvent burst is
+	// being coalesced. The leading edge fires immediately; subsequent calls
+	// within the debounce window set widgetUpdateTrailing so a final event
+	// is delivered with the latest runner state at the end of the window.
+	// Without the trailing send, a rapid SetWidget→RemoveWidget pair (e.g.
+	// SubagentEnd pushing a final frame then removing the widget) would let
+	// the second call get silently dropped, leaving the TUI's layout stuck
+	// on the pre-removal widget height — visible as empty rows below the
+	// status bar after the widget disappears.
+	widgetUpdatePending  atomic.Bool
+	widgetUpdateTrailing atomic.Bool
+
+	// steerDrainFn is the test seam used by releaseBusyAfterCompact to pull
+	// any steer messages that arrived during compaction. In production it is
+	// nil and the helper falls back to a.opts.Kit.DrainSteer(); tests that
+	// need to exercise the steer-drain path without standing up a full
+	// *kit.Kit can set this field directly to inject fake items.
+	steerDrainFn func() []queueItem
 }
 
 // New creates a new App with the provided options and pre-loaded messages.
@@ -356,6 +366,10 @@ func (a *App) AddContextMessage(text string) {
 // tea.Program. customInstructions is optional text appended to the summary
 // prompt (e.g. "Focus on the API design decisions").
 //
+// Any prompts queued via Run/RunWithFiles or steering messages injected via
+// Steer/SteerWithFiles while compaction is running are flushed automatically
+// once compaction completes (see releaseBusyAfterCompact).
+//
 // Satisfies ui.AppController.
 func (a *App) CompactConversation(customInstructions string) error {
 	a.mu.Lock()
@@ -377,11 +391,7 @@ func (a *App) CompactConversation(customInstructions string) error {
 
 	go func() {
 		defer a.wg.Done()
-		defer func() {
-			a.mu.Lock()
-			a.busy = false
-			a.mu.Unlock()
-		}()
+		defer a.releaseBusyAfterCompact()
 
 		// Subscribe to SDK events for streaming compaction summary to the TUI.
 		sendFn := func(msg tea.Msg) {
@@ -420,6 +430,9 @@ func (a *App) CompactConversation(customInstructions string) error {
 // CompactAsync is like CompactConversation but calls onComplete/onError
 // callbacks instead of sending TUI events. Used by the extension API's
 // ctx.Compact() which needs callback-based notification.
+//
+// Like CompactConversation, any prompts/steer messages received during
+// compaction are flushed automatically once compaction finishes.
 func (a *App) CompactAsync(customInstructions string, onComplete func(), onError func(string)) error {
 	a.mu.Lock()
 	if a.closed {
@@ -440,11 +453,7 @@ func (a *App) CompactAsync(customInstructions string, onComplete func(), onError
 
 	go func() {
 		defer a.wg.Done()
-		defer func() {
-			a.mu.Lock()
-			a.busy = false
-			a.mu.Unlock()
-		}()
+		defer a.releaseBusyAfterCompact()
 
 		// Subscribe to SDK events for streaming compaction summary to the TUI.
 		sendFn := func(msg tea.Msg) {
@@ -489,6 +498,81 @@ func (a *App) CompactAsync(customInstructions string, onComplete func(), onError
 	return nil
 }
 
+// releaseBusyAfterCompact is the deferred tail that runs at the end of every
+// compaction goroutine (success, error, or panic-after-recover paths). It
+// flips a.busy back to false, but before doing so it checks whether any
+// prompts piled up while compaction was running:
+//
+//   - Run/RunWithFiles append to a.queue when a.busy is set.
+//   - Steer/SteerWithFiles deposit messages into the SDK steer channel via
+//     Kit.InjectSteerWithFiles when a.busy is set.
+//
+// Without this hand-off the queue would sit idle until the user submits
+// another prompt — see issue #27. If we find anything pending we keep busy
+// set, splice the steer messages to the front of the queue, and start a
+// fresh drainQueue goroutine to deliver them as a single batched turn.
+func (a *App) releaseBusyAfterCompact() {
+	// Pull steer messages outside the app mutex; DrainSteer takes its own
+	// internal lock and we don't want to nest the two. The test seam
+	// (a.steerDrainFn) takes precedence so unit tests can inject fake
+	// steer items without a real *kit.Kit.
+	var steerItems []queueItem
+	switch {
+	case a.steerDrainFn != nil:
+		steerItems = a.steerDrainFn()
+	case a.opts.Kit != nil:
+		if leftover := a.opts.Kit.DrainSteer(); len(leftover) > 0 {
+			steerItems = make([]queueItem, len(leftover))
+			for i, sm := range leftover {
+				steerItems[i] = queueItem{Prompt: sm.Text, Files: sm.Files}
+			}
+		}
+	}
+
+	a.mu.Lock()
+	// If the app was closed while compaction was running, drop everything
+	// and just clear busy. Run/Steer would have rejected new items already
+	// after Close(), but this guards against in-flight items that slipped
+	// in just before closed was set.
+	if a.closed {
+		a.queue = a.queue[:0]
+		a.busy = false
+		a.mu.Unlock()
+		return
+	}
+
+	// Combine steer-channel items (front) with the in-memory queue (back).
+	// Steer messages are placed first so they retain their "act now"
+	// semantics relative to ordinary queued prompts that arrived later.
+	pending := append(steerItems, a.queue...)
+	a.queue = a.queue[:0]
+
+	if len(pending) == 0 {
+		a.busy = false
+		a.mu.Unlock()
+		return
+	}
+
+	// Hand off to drainQueue: it will pick up the first item directly and
+	// scoop the rest from a.queue on its first iteration.
+	first := pending[0]
+	if len(pending) > 1 {
+		a.queue = append(a.queue, pending[1:]...)
+	}
+	// Stay busy across the goroutine swap.
+	a.wg.Add(1)
+	a.mu.Unlock()
+
+	// Notify the UI that steer-channel messages were consumed so the
+	// steering badge can clear; ordinary queued prompts will be reflected
+	// by the QueueUpdatedEvent that drainQueue emits as it picks them up.
+	if len(steerItems) > 0 {
+		a.sendEvent(SteerConsumedEvent{})
+	}
+
+	go a.drainQueue(first)
+}
+
 // --------------------------------------------------------------------------
 // Non-interactive execution
 // --------------------------------------------------------------------------
@@ -1076,32 +1160,47 @@ func (a *App) NotifyModelChanged(provider, model string) {
 // extension widgets. Called from the extension context's SetWidget/RemoveWidget
 // closures. In non-interactive mode this is a no-op (widgets are TUI-only).
 //
-// Coalescing: if a WidgetUpdateEvent is already queued and not yet consumed
-// by the TUI event loop, additional calls within the same ~16 ms window are
-// dropped. This prevents fast extension tickers from flooding BubbleTea's
-// mailbox with redundant re-render triggers.
+// Coalescing (leading + trailing edge): the first call in an idle period
+// fires immediately for responsiveness. Subsequent calls within a ~16 ms
+// debounce window are batched into a single trailing event delivered at
+// the end of the window. The trailing send is essential for correctness:
+// extensions routinely make tight SetWidget→RemoveWidget pairs (e.g. on
+// SubagentEnd) and silently dropping the second call would leave the TUI's
+// layout stuck on stale widget dimensions until some other event happens
+// to trigger a re-render.
 func (a *App) NotifyWidgetUpdate() {
-	// Coalesce: only one pending update at a time.
 	if !a.widgetUpdatePending.CompareAndSwap(false, true) {
+		// A leading-edge event is already in flight — mark that the runner
+		// state has changed again so the trailing send below picks it up.
+		a.widgetUpdateTrailing.Store(true)
 		return
 	}
 	a.mu.Lock()
 	prog := a.program
 	a.mu.Unlock()
-	if prog != nil {
-		prog.Send(WidgetUpdateEvent{})
-		// Reset the pending flag after a short debounce so subsequent calls
-		// within the same render cycle are also coalesced, but new updates
-		// after the cycle are allowed through.
-		go func() {
-			time.Sleep(16 * time.Millisecond) // ~1 frame at 60 fps
-			a.widgetUpdatePending.Store(false)
-		}()
-	} else {
+	if prog == nil {
 		// No program registered (non-interactive mode); clear the flag so
 		// future calls are never permanently blocked.
 		a.widgetUpdatePending.Store(false)
+		return
 	}
+	prog.Send(WidgetUpdateEvent{})
+	go func() {
+		time.Sleep(16 * time.Millisecond) // ~1 frame at 60 fps
+		// If any extra calls came in during the debounce window, deliver
+		// one trailing event so the TUI sees the latest widget state. We
+		// swap-and-test instead of plain-load so concurrent calls after
+		// the trailing send still race correctly with the pending reset.
+		if a.widgetUpdateTrailing.Swap(false) {
+			a.mu.Lock()
+			p := a.program
+			a.mu.Unlock()
+			if p != nil {
+				p.Send(WidgetUpdateEvent{})
+			}
+		}
+		a.widgetUpdatePending.Store(false)
+	}()
 }
 
 // NotifyContentReload sends a ContentReloadEvent to the TUI so it refreshes

internal/app/app_test.go

@@ -763,3 +763,209 @@ func TestFormatMaxTokensTruncatedMessage_NoKit(t *testing.T) {
 		}
 	}
 }
+
+// --------------------------------------------------------------------------
+// releaseBusyAfterCompact (issue #27)
+// --------------------------------------------------------------------------
+
+// TestReleaseBusyAfterCompact_flushesQueuedMessages is a regression test for
+// issue #27: messages queued via Run() while /compact is running used to sit
+// in a.queue indefinitely until the user typed another prompt. After the fix
+// the deferred releaseBusyAfterCompact tail picks up any pending items and
+// dispatches drainQueue automatically.
+//
+// We simulate the compaction completion path directly (bypassing the SDK)
+// by toggling busy=true, populating the queue exactly as Run() would have
+// during compaction, and then invoking releaseBusyAfterCompact.
+func TestReleaseBusyAfterCompact_flushesQueuedMessages(t *testing.T) {
+	stub := newStubWithFuncs(
+		func(ctx context.Context) (*kit.TurnResult, error) {
+			return turnResult("compacted then drained"), nil
+		},
+	)
+	app := newTestApp(stub)
+	defer app.Close()
+
+	// Simulate the state at the start of the compaction tail: busy is set
+	// and a couple of prompts have piled up in the queue while we were
+	// summarising. (Run() would have appended them and returned a queue
+	// length > 0 to the caller.)
+	app.mu.Lock()
+	app.busy = true
+	app.queue = append(app.queue,
+		queueItem{Prompt: "queued during compact #1"},
+		queueItem{Prompt: "queued during compact #2"},
+	)
+	app.mu.Unlock()
+
+	// Invoke the deferred tail directly. It should kick off drainQueue.
+	app.releaseBusyAfterCompact()
+
+	// drainQueue runs in a goroutine. Wait for the app to come back to idle.
+	ok := waitForCondition(2*time.Second, func() bool {
+		app.mu.Lock()
+		defer app.mu.Unlock()
+		return !app.busy
+	})
+	if !ok {
+		t.Fatal("app did not become idle after releaseBusyAfterCompact: queue not drained")
+	}
+
+	// Wait for any in-flight goroutine to finish before reading state.
+	app.wg.Wait()
+
+	if got := app.QueueLength(); got != 0 {
+		t.Fatalf("expected empty queue after drain, got %d", got)
+	}
+	if n := stub.callCount(); n == 0 {
+		t.Fatalf("expected stub PromptFunc to fire at least once after compact, got %d calls", n)
+	}
+}
+
+// TestReleaseBusyAfterCompact_idleWhenQueueEmpty verifies that with no
+// pending messages the helper just clears busy and does NOT spawn a
+// drainQueue goroutine (no spurious agent turn).
+func TestReleaseBusyAfterCompact_idleWhenQueueEmpty(t *testing.T) {
+	stub := newStub()
+	app := newTestApp(stub)
+	defer app.Close()
+
+	app.mu.Lock()
+	app.busy = true
+	app.mu.Unlock()
+
+	app.releaseBusyAfterCompact()
+
+	app.mu.Lock()
+	busy := app.busy
+	app.mu.Unlock()
+	if busy {
+		t.Fatal("expected busy=false after releaseBusyAfterCompact with empty queue")
+	}
+
+	// Give any rogue goroutine a moment to (incorrectly) call PromptFunc.
+	time.Sleep(50 * time.Millisecond)
+	if n := stub.callCount(); n != 0 {
+		t.Fatalf("expected 0 PromptFunc calls when queue empty, got %d", n)
+	}
+}
+
+// TestReleaseBusyAfterCompact_splicesSteerAheadOfQueue exercises the SDK
+// steer-drain branch of releaseBusyAfterCompact (issue #27 follow-up).
+//
+// Production wires a.opts.Kit.DrainSteer() to pull messages that arrived via
+// Steer/SteerWithFiles during compaction, but Options.Kit is *kit.Kit (a
+// concrete struct) so unit tests cannot stand up a real instance without a
+// full LLM backend. The test uses the unexported steerDrainFn seam to inject
+// fake steer items, then asserts that:
+//
+//   - Steer items are dispatched ahead of any prompts that piled up in
+//     a.queue (steer retains "act now" priority over ordinary queued
+//     prompts), and
+//   - the helper still hands off to drainQueue so the steer item actually
+//     fires (the previous behaviour left them stranded — see #27).
+func TestReleaseBusyAfterCompact_splicesSteerAheadOfQueue(t *testing.T) {
+	var pmu sync.Mutex
+	var firstPrompt string
+	stub := newStubWithFuncs(
+		func(ctx context.Context) (*kit.TurnResult, error) {
+			return turnResult("steer dispatched"), nil
+		},
+	)
+	// Wrap PromptFunc so we can capture the prompt text the stub receives
+	// (newStubWithFuncs's fns ignore prompt; we need it to verify ordering).
+	capturingPrompt := func(ctx context.Context, prompt string) (*kit.TurnResult, error) {
+		pmu.Lock()
+		if firstPrompt == "" {
+			firstPrompt = prompt
+		}
+		pmu.Unlock()
+		return stub.fn(ctx, prompt)
+	}
+	app := New(Options{PromptFunc: capturingPrompt}, nil)
+	defer app.Close()
+
+	// Inject fake steer items via the test seam. In production the same
+	// items would have been delivered through Kit.InjectSteerWithFiles
+	// during /compact and pulled by DrainSteer here.
+	app.steerDrainFn = func() []queueItem {
+		return []queueItem{
+			{Prompt: "steer-1"},
+			{Prompt: "steer-2"},
+		}
+	}
+
+	// Simulate the state at the end of compaction: busy is set and a couple
+	// of regular Run() prompts have piled up after the steer messages.
+	app.mu.Lock()
+	app.busy = true
+	app.queue = append(app.queue,
+		queueItem{Prompt: "queued-1"},
+		queueItem{Prompt: "queued-2"},
+	)
+	app.mu.Unlock()
+
+	app.releaseBusyAfterCompact()
+
+	// Wait for the dispatched batch to complete.
+	ok := waitForCondition(2*time.Second, func() bool {
+		app.mu.Lock()
+		defer app.mu.Unlock()
+		return !app.busy
+	})
+	if !ok {
+		t.Fatal("app did not become idle after steer-spliced releaseBusyAfterCompact")
+	}
+	app.wg.Wait()
+
+	// drainQueue picks up `first` directly and batches the rest. With
+	// PromptFunc set, executeBatch invokes us with items[0] only — that
+	// item must be the first steer message, proving steer items were
+	// spliced ahead of the previously queued prompts.
+	pmu.Lock()
+	got := firstPrompt
+	pmu.Unlock()
+	if got != "steer-1" {
+		t.Fatalf("expected first dispatched prompt to be steer item %q (steer items must come before queued prompts), got %q",
+			"steer-1", got)
+	}
+
+	// Queue should be fully drained and PromptFunc must have actually fired.
+	if n := app.QueueLength(); n != 0 {
+		t.Fatalf("expected empty queue after drain, got %d entries", n)
+	}
+	if n := stub.callCount(); n == 0 {
+		t.Fatal("expected stub PromptFunc to fire at least once after splice")
+	}
+}
+
+// TestReleaseBusyAfterCompact_dropsQueueWhenClosed verifies that if the app
+// was closed during compaction the helper discards any pending items rather
+// than spawning drainQueue against a torn-down App.
+func TestReleaseBusyAfterCompact_dropsQueueWhenClosed(t *testing.T) {
+	stub := newStub()
+	app := newTestApp(stub)
+
+	app.mu.Lock()
+	app.busy = true
+	app.queue = append(app.queue, queueItem{Prompt: "would have run"})
+	app.closed = true
+	app.mu.Unlock()
+
+	app.releaseBusyAfterCompact()
+
+	app.mu.Lock()
+	busy := app.busy
+	qLen := len(app.queue)
+	app.mu.Unlock()
+	if busy {
+		t.Fatal("expected busy=false even when closed")
+	}
+	if qLen != 0 {
+		t.Fatalf("expected queue cleared on closed app, got %d entries", qLen)
+	}
+	time.Sleep(20 * time.Millisecond)
+	if n := stub.callCount(); n != 0 {
+		t.Fatalf("expected 0 PromptFunc calls on closed app, got %d", n)
+	}
+}

internal/auth/credentials.go

@@ -255,29 +255,6 @@ func (cm *CredentialManager) HasAnthropicCredentials() (bool, error) {
 	}
 }
 
-// SetOpenAICredentials stores OpenAI API key credentials. It validates the
-// API key format before storing. The API key must start with "sk-" and be
-// at least 20 characters long. Returns an error if the API key is invalid or
-// if storage fails.
-func (cm *CredentialManager) SetOpenAICredentials(apiKey string) error {
-	if err := validateOpenAIAPIKey(apiKey); err != nil {
-		return err
-	}
-
-	store, err := cm.LoadCredentials()
-	if err != nil {
-		return err
-	}
-
-	store.OpenAI = &OpenAICredentials{
-		Type:      "api_key",
-		APIKey:    apiKey,
-		CreatedAt: time.Now(),
-	}
-
-	return cm.SaveCredentials(store)
-}
-
 // GetOpenAICredentials retrieves stored OpenAI credentials. Returns nil if
 // no credentials are stored. The returned credentials may be either OAuth or API
 // key type, check the Type field to determine which.
@@ -417,26 +394,6 @@ func validateAnthropicAPIKey(apiKey string) error {
 	return nil
 }
 
-// validateOpenAIAPIKey validates the format of an OpenAI API key
-func validateOpenAIAPIKey(apiKey string) error {
-	apiKey = strings.TrimSpace(apiKey)
-
-	if apiKey == "" {
-		return fmt.Errorf("API key cannot be empty")
-	}
-
-	// OpenAI API keys typically start with "sk-" and are quite long
-	if !strings.HasPrefix(apiKey, "sk-") {
-		return fmt.Errorf("invalid OpenAI API key format (should start with 'sk-')")
-	}
-
-	if len(apiKey) < 20 {
-		return fmt.Errorf("API key appears to be too short")
-	}
-
-	return nil
-}
-
 // GetAnthropicAPIKey retrieves an Anthropic API key from multiple sources in priority order:
 // 1. Command-line flag value (highest priority)
 // 2. Stored credentials (OAuth or API key)

internal/config/config.go

@@ -38,6 +38,23 @@ type MCPServerConfig struct {
 	// servers that don't support it.
 	NoOAuth bool `json:"noOAuth,omitempty" yaml:"noOAuth,omitempty"`
 
+	// TasksMode controls when this server's tools/call requests are augmented
+	// with MCP task metadata (turning a synchronous call into an asynchronous,
+	// pollable job — see https://modelcontextprotocol.io/specification/2025-11-25/basic/utilities/tasks).
+	//
+	// Valid values:
+	//   - "" or "auto": (default) augment requests with task metadata only
+	//     when the server advertises tasks/toolCalls capability during initialize.
+	//   - "never":      never augment — every tool call is synchronous, regardless
+	//     of server capability.
+	//   - "always":     always augment, even when the server didn't advertise
+	//     task support. The server may still respond synchronously; this just
+	//     opts in unconditionally on the client side.
+	//
+	// In all modes, when the server returns a CreateTaskResult the client polls
+	// tasks/get / tasks/result until the task reaches a terminal state.
+	TasksMode string `json:"tasksMode,omitempty" yaml:"tasksMode,omitempty"`
+
 	// InProcessServer holds a live *server.MCPServer for in-process transport.
 	// When set (and Type is "inprocess"), the connection pool creates an
 	// in-process client instead of spawning a subprocess or making HTTP calls.
@@ -68,6 +85,7 @@ func (s *MCPServerConfig) UnmarshalJSON(data []byte) error {
 		OAuthClientSecret string            `json:"oauthClientSecret,omitempty" yaml:"oauthClientSecret,omitempty"`
 		OAuthScopes       []string          `json:"oauthScopes,omitempty" yaml:"oauthScopes,omitempty"`
 		NoOAuth           bool              `json:"noOAuth,omitempty" yaml:"noOAuth,omitempty"`
+		TasksMode         string            `json:"tasksMode,omitempty" yaml:"tasksMode,omitempty"`
 	}
 
 	// Also try legacy format
@@ -80,6 +98,7 @@ func (s *MCPServerConfig) UnmarshalJSON(data []byte) error {
 		Headers       []string       `json:"headers,omitempty"`
 		AllowedTools  []string       `json:"allowedTools,omitempty" yaml:"allowedTools,omitempty"`
 		ExcludedTools []string       `json:"excludedTools,omitempty" yaml:"excludedTools,omitempty"`
+		TasksMode     string         `json:"tasksMode,omitempty" yaml:"tasksMode,omitempty"`
 	}
 
 	// Try new format first
@@ -96,6 +115,7 @@ func (s *MCPServerConfig) UnmarshalJSON(data []byte) error {
 		s.OAuthClientSecret = newConfig.OAuthClientSecret
 		s.OAuthScopes = newConfig.OAuthScopes
 		s.NoOAuth = newConfig.NoOAuth
+		s.TasksMode = newConfig.TasksMode
 		return nil
 	}
 
@@ -116,6 +136,7 @@ func (s *MCPServerConfig) UnmarshalJSON(data []byte) error {
 	s.Headers = legacyConfig.Headers
 	s.AllowedTools = legacyConfig.AllowedTools
 	s.ExcludedTools = legacyConfig.ExcludedTools
+	s.TasksMode = legacyConfig.TasksMode
 
 	// Infer type from legacy format for better compatibility
 	// Only set Type when it doesn't change existing transport behavior
@@ -324,6 +345,17 @@ func (c *Config) Validate() error {
 			return fmt.Errorf("server %s: allowedTools and excludedTools are mutually exclusive", serverName)
 		}
 
+		// Reject unknown tasksMode values up front so a typo (e.g. "alwasy")
+		// fails loud here instead of being silently downgraded to "auto" by
+		// the runtime parser. Comparison is case-insensitive to match
+		// tools.ParseTaskMode.
+		switch strings.ToLower(strings.TrimSpace(serverConfig.TasksMode)) {
+		case "", "auto", "never", "always":
+			// ok
+		default:
+			return fmt.Errorf("server %s: invalid tasksMode %q (expected one of: auto, never, always)", serverName, serverConfig.TasksMode)
+		}
+
 		transport := serverConfig.GetTransportType()
 		switch transport {
 		case "stdio":

internal/config/config_test.go

@@ -627,3 +627,92 @@ func TestMCPServerConfig_OAuthFields_Omitted(t *testing.T) {
 		t.Errorf("Expected empty OAuthScopes, got %v", cfg.OAuthScopes)
 	}
 }
+
+func TestMCPServerConfig_TasksMode_NewFormat(t *testing.T) {
+	jsonData := `{
+		"type": "remote",
+		"url": "https://my-mcp-server.com",
+		"tasksMode": "always"
+	}`
+	var cfg MCPServerConfig
+	if err := json.Unmarshal([]byte(jsonData), &cfg); err != nil {
+		t.Fatalf("Failed to unmarshal: %v", err)
+	}
+	if cfg.TasksMode != "always" {
+		t.Errorf("expected TasksMode 'always', got %q", cfg.TasksMode)
+	}
+}
+
+func TestMCPServerConfig_TasksMode_LegacyFormat(t *testing.T) {
+	// tasksMode also recognised in the legacy unmarshal path so users on
+	// the older command/args shape can opt in without migrating.
+	jsonData := `{
+		"command": "npx",
+		"args": ["@modelcontextprotocol/server-filesystem", "/path"],
+		"tasksMode": "never"
+	}`
+	var cfg MCPServerConfig
+	if err := json.Unmarshal([]byte(jsonData), &cfg); err != nil {
+		t.Fatalf("Failed to unmarshal: %v", err)
+	}
+	if cfg.TasksMode != "never" {
+		t.Errorf("expected TasksMode 'never', got %q", cfg.TasksMode)
+	}
+}
+
+func TestMCPServerConfig_TasksMode_DefaultEmpty(t *testing.T) {
+	// When tasksMode is not set the field stays empty, which downstream
+	// resolves to "auto" via tools.ParseTaskMode.
+	jsonData := `{"type":"remote","url":"https://x.example"}`
+	var cfg MCPServerConfig
+	if err := json.Unmarshal([]byte(jsonData), &cfg); err != nil {
+		t.Fatalf("Failed to unmarshal: %v", err)
+	}
+	if cfg.TasksMode != "" {
+		t.Errorf("expected default TasksMode to be empty, got %q", cfg.TasksMode)
+	}
+}
+
+func TestConfig_Validate_TasksMode(t *testing.T) {
+	t.Run("empty is valid", func(t *testing.T) {
+		cfg := &Config{
+			MCPServers: map[string]MCPServerConfig{
+				"a": {Type: "remote", URL: "https://x.example"},
+			},
+		}
+		if err := cfg.Validate(); err != nil {
+			t.Errorf("empty TasksMode should validate, got %v", err)
+		}
+	})
+
+	t.Run("known values are valid", func(t *testing.T) {
+		for _, mode := range []string{"auto", "never", "always", "AUTO", " always "} {
+			cfg := &Config{
+				MCPServers: map[string]MCPServerConfig{
+					"a": {Type: "remote", URL: "https://x.example", TasksMode: mode},
+				},
+			}
+			if err := cfg.Validate(); err != nil {
+				t.Errorf("TasksMode=%q should validate, got %v", mode, err)
+			}
+		}
+	})
+
+	t.Run("typo is rejected with a clear error", func(t *testing.T) {
+		cfg := &Config{
+			MCPServers: map[string]MCPServerConfig{
+				"buildbot": {Type: "remote", URL: "https://x.example", TasksMode: "alwasy"},
+			},
+		}
+		err := cfg.Validate()
+		if err == nil {
+			t.Fatal("expected validation error for invalid TasksMode")
+		}
+		// Error must mention the server name AND the bad value so the
+		// user knows where to look.
+		msg := err.Error()
+		if !strings.Contains(msg, "buildbot") || !strings.Contains(msg, `"alwasy"`) {
+			t.Errorf("error %q should mention both server name and bad value", msg)
+		}
+	})
+}

internal/core/bash.go

@@ -160,15 +160,6 @@ func rewriteSudoForStdin(command string) string {
 	return result
 }
 
-// SudoPasswordRequiredResult is a special marker that indicates sudo needs a password.
-// This is stored in tool response metadata to signal the TUI to prompt for password.
-const SudoPasswordRequiredMetadata = `{"sudo_password_required":true}`
-
-// IsSudoPasswordRequiredResult checks if a tool response indicates sudo password is needed.
-func IsSudoPasswordRequiredResult(resp fantasy.ToolResponse) bool {
-	return resp.Metadata == SudoPasswordRequiredMetadata
-}
-
 func executeBash(ctx context.Context, call fantasy.ToolCall, workDir string) (fantasy.ToolResponse, error) {
 	var args bashArgs
 	if err := parseArgs(call.Input, &args); err != nil {

internal/core/edit.go

@@ -21,12 +21,9 @@ type Edit struct {
 }
 
 // editArgs holds the arguments for the edit tool.
-// Supports both single-edit mode (old_text/new_text) and multi-edit mode (edits array).
 type editArgs struct {
-	Path    string `json:"path"`
-	OldText string `json:"old_text"` // Single-edit mode
-	NewText string `json:"new_text"` // Single-edit mode
-	Edits   []Edit `json:"edits"`    // Multi-edit mode
+	Path  string `json:"path"`
+	Edits []Edit `json:"edits"`
 }
 
 // replacement represents a normalized edit ready for processing.
@@ -52,20 +49,12 @@ func NewEditTool(opts ...ToolOption) fantasy.AgentTool {
 	return &coreTool{
 		info: fantasy.ToolInfo{
 			Name:        "edit",
-			Description: "Edit a file by replacing exact text. Supports single edit via old_text/new_text, or multiple edits via the edits array. All edits in the array are matched against the original file content (non-incremental) and must be non-overlapping.",
+			Description: "Edit a file by replacing exact text. All edits in the array are matched against the original file content (non-incremental) and must be non-overlapping.",
 			Parameters: map[string]any{
 				"path": map[string]any{
 					"type":        "string",
 					"description": "Path to the file to edit (relative or absolute)",
 				},
-				"old_text": map[string]any{
-					"type":        "string",
-					"description": "Exact text to find and replace (single-edit mode). Must not be used with 'edits' array.",
-				},
-				"new_text": map[string]any{
-					"type":        "string",
-					"description": "New text to replace the old text with (single-edit mode). Must not be used with 'edits' array.",
-				},
 				"edits": map[string]any{
 					"type":        "array",
 					"description": "Array of edits for multi-region replacement. Each edit must have unique, non-overlapping old_text. All matches are against the original file content.",
@@ -85,7 +74,7 @@ func NewEditTool(opts ...ToolOption) fantasy.AgentTool {
 					},
 				},
 			},
-			Required: []string{"path"},
+			Required: []string{"path", "edits"},
 		},
 		handler: func(ctx context.Context, call fantasy.ToolCall) (fantasy.ToolResponse, error) {
 			return executeEdit(ctx, call, cfg.WorkDir)
@@ -163,36 +152,11 @@ func executeEdit(ctx context.Context, call fantasy.ToolCall, workDir string) (fa
 }
 
 // normalizeEditInput validates and normalizes the edit input.
-// Returns error if both single-edit and multi-edit modes are used.
 func normalizeEditInput(args editArgs) ([]replacement, error) {
-	singleMode := args.OldText != "" || args.NewText != ""
-	multiMode := len(args.Edits) > 0
-
-	if singleMode && multiMode {
-		return nil, fmt.Errorf("cannot use old_text/new_text together with edits array")
+	if len(args.Edits) == 0 {
+		return nil, fmt.Errorf("edits array is required and must not be empty")
 	}
 
-	if !singleMode && !multiMode {
-		return nil, fmt.Errorf("must provide either old_text/new_text or edits array")
-	}
-
-	if singleMode {
-		if args.OldText == "" {
-			return nil, fmt.Errorf("old_text is required when using single-edit mode")
-		}
-		if args.NewText == "" {
-			return nil, fmt.Errorf("new_text is required when using single-edit mode")
-		}
-		return []replacement{{
-			oldText:     strings.ReplaceAll(args.OldText, "\r\n", "\n"),
-			newText:     strings.ReplaceAll(args.NewText, "\r\n", "\n"),
-			originalOld: args.OldText,
-			originalNew: args.NewText,
-			index:       0,
-		}}, nil
-	}
-
-	// Multi-edit mode
 	var reps []replacement
 	for i, edit := range args.Edits {
 		if edit.OldText == "" {

internal/core/edit_test.go

@@ -389,9 +389,11 @@ func TestExecuteEdit_ExactMatch(t *testing.T) {
 	writeFileOrFail(t, path, original)
 
 	input, _ := json.Marshal(editArgs{
-		Path:    path,
-		OldText: "fmt.Println(\"hello\")",
-		NewText: "fmt.Println(\"world\")",
+		Path: path,
+		Edits: []Edit{{
+			OldText: "fmt.Println(\"hello\")",
+			NewText: "fmt.Println(\"world\")",
+		}},
 	})
 
 	resp, err := executeEdit(t.Context(), fantasy.ToolCall{Input: string(input)}, dir)
@@ -426,9 +428,11 @@ func TestExecuteEdit_ExactMatch_DoesNotCorruptRest(t *testing.T) {
 	target := lines[49]
 	replacement := "REPLACED_LINE_50"
 	input, _ := json.Marshal(editArgs{
-		Path:    path,
-		OldText: target,
-		NewText: replacement,
+		Path: path,
+		Edits: []Edit{{
+			OldText: target,
+			NewText: replacement,
+		}},
 	})
 
 	resp, err := executeEdit(t.Context(), fantasy.ToolCall{Input: string(input)}, dir)
@@ -470,9 +474,11 @@ func TestExecuteEdit_FuzzyMatch_TrailingWhitespace(t *testing.T) {
 
 	// Search without trailing whitespace (common LLM behavior)
 	input, _ := json.Marshal(editArgs{
-		Path:    path,
-		OldText: "func foo() {\n\treturn 1\n}",
-		NewText: "func foo() {\n\treturn 2\n}",
+		Path: path,
+		Edits: []Edit{{
+			OldText: "func foo() {\n\treturn 1\n}",
+			NewText: "func foo() {\n\treturn 2\n}",
+		}},
 	})
 
 	resp, err := executeEdit(t.Context(), fantasy.ToolCall{Input: string(input)}, dir)
@@ -519,9 +525,11 @@ func TestExecuteEdit_FuzzyMatch_DoesNotCorruptRest(t *testing.T) {
 	search := strings.Repeat("x", 10) + "\n" + strings.Repeat("x", 10)
 	// But this matches lines 1-2, 2-3, etc. — should fail due to ambiguity.
 	input, _ := json.Marshal(editArgs{
-		Path:    path,
-		OldText: search,
-		NewText: "REPLACED",
+		Path: path,
+		Edits: []Edit{{
+			OldText: search,
+			NewText: "REPLACED",
+		}},
 	})
 
 	resp, err := executeEdit(t.Context(), fantasy.ToolCall{Input: string(input)}, dir)
@@ -546,9 +554,11 @@ func TestExecuteEdit_MultipleMatches_Fails(t *testing.T) {
 	writeFileOrFail(t, path, "hello\nworld\nhello\n")
 
 	input, _ := json.Marshal(editArgs{
-		Path:    path,
-		OldText: "hello",
-		NewText: "goodbye",
+		Path: path,
+		Edits: []Edit{{
+			OldText: "hello",
+			NewText: "goodbye",
+		}},
 	})
 
 	resp, err := executeEdit(t.Context(), fantasy.ToolCall{Input: string(input)}, dir)
@@ -575,9 +585,11 @@ func TestExecuteEdit_NoMatch_Fails(t *testing.T) {
 	writeFileOrFail(t, path, "hello world\n")
 
 	input, _ := json.Marshal(editArgs{
-		Path:    path,
-		OldText: "nonexistent text",
-		NewText: "replacement",
+		Path: path,
+		Edits: []Edit{{
+			OldText: "nonexistent text",
+			NewText: "replacement",
+		}},
 	})
 
 	resp, err := executeEdit(t.Context(), fantasy.ToolCall{Input: string(input)}, dir)
@@ -601,9 +613,11 @@ func TestExecuteEdit_CRLFNormalization(t *testing.T) {
 	writeFileOrFail(t, path, "line1\r\nline2\r\nline3\r\n")
 
 	input, _ := json.Marshal(editArgs{
-		Path:    path,
-		OldText: "line2",
-		NewText: "LINE2",
+		Path: path,
+		Edits: []Edit{{
+			OldText: "line2",
+			NewText: "LINE2",
+		}},
 	})
 
 	resp, err := executeEdit(t.Context(), fantasy.ToolCall{Input: string(input)}, dir)
@@ -622,8 +636,10 @@ func TestExecuteEdit_CRLFNormalization(t *testing.T) {
 
 func TestExecuteEdit_MissingPath(t *testing.T) {
 	input, _ := json.Marshal(editArgs{
-		OldText: "x",
-		NewText: "y",
+		Edits: []Edit{{
+			OldText: "x",
+			NewText: "y",
+		}},
 	})
 	resp, err := executeEdit(t.Context(), fantasy.ToolCall{Input: string(input)}, "")
 	if err != nil {
@@ -636,9 +652,11 @@ func TestExecuteEdit_MissingPath(t *testing.T) {
 
 func TestExecuteEdit_NonexistentFile(t *testing.T) {
 	input, _ := json.Marshal(editArgs{
-		Path:    "/tmp/nonexistent_edit_test_file_12345.go",
-		OldText: "x",
-		NewText: "y",
+		Path: "/tmp/nonexistent_edit_test_file_12345.go",
+		Edits: []Edit{{
+			OldText: "x",
+			NewText: "y",
+		}},
 	})
 	resp, err := executeEdit(t.Context(), fantasy.ToolCall{Input: string(input)}, "")
 	if err != nil {
@@ -661,9 +679,11 @@ func TestExecuteEdit_DiffContainsHunkHeader(t *testing.T) {
 	writeFileOrFail(t, path, strings.Join(lines, "\n")+"\n")
 
 	input, _ := json.Marshal(editArgs{
-		Path:    path,
-		OldText: "line_10_content",
-		NewText: "REPLACED",
+		Path: path,
+		Edits: []Edit{{
+			OldText: "line_10_content",
+			NewText: "REPLACED",
+		}},
 	})
 
 	resp, err := executeEdit(t.Context(), fantasy.ToolCall{Input: string(input)}, dir)
@@ -684,9 +704,11 @@ func TestExecuteEdit_MetadataContainsFileDiffs(t *testing.T) {
 	writeFileOrFail(t, path, "old content\n")
 
 	input, _ := json.Marshal(editArgs{
-		Path:    path,
-		OldText: "old content",
-		NewText: "new content",
+		Path: path,
+		Edits: []Edit{{
+			OldText: "old content",
+			NewText: "new content",
+		}},
 	})
 
 	resp, err := executeEdit(t.Context(), fantasy.ToolCall{Input: string(input)}, dir)
@@ -905,18 +927,14 @@ func TestExecuteEdit_MultiEdit_EmptyArray(t *testing.T) {
 	}
 }
 
-func TestExecuteEdit_MultiEdit_MixedWithSingleMode(t *testing.T) {
+func TestExecuteEdit_EmptyEditsArray_Fails(t *testing.T) {
 	dir := t.TempDir()
-	path := filepath.Join(dir, "mixed.txt")
+	path := filepath.Join(dir, "empty.txt")
 	writeFileOrFail(t, path, "hello\n")
 
-	input, _ := json.Marshal(map[string]any{
-		"path":     path,
-		"old_text": "hello",
-		"new_text": "HELLO",
-		"edits": []Edit{
-			{OldText: "hello", NewText: "HI"},
-		},
+	input, _ := json.Marshal(editArgs{
+		Path:  path,
+		Edits: []Edit{},
 	})
 
 	resp, err := executeEdit(t.Context(), fantasy.ToolCall{Input: string(input)}, dir)
@@ -924,10 +942,10 @@ func TestExecuteEdit_MultiEdit_MixedWithSingleMode(t *testing.T) {
 		t.Fatalf("executeEdit error: %v", err)
 	}
 	if !resp.IsError {
-		t.Error("expected error when mixing single and multi-edit modes")
+		t.Error("expected error for empty edits array")
 	}
-	if !strings.Contains(resp.Content, "cannot use") {
-		t.Errorf("expected 'cannot use' in error, got: %s", resp.Content)
+	if !strings.Contains(resp.Content, "required") {
+		t.Errorf("expected 'required' in error, got: %s", resp.Content)
 	}
 }
 

internal/extbridge/extbridge.go

@@ -0,0 +1,97 @@
+// Package extbridge wires the public Kit SDK to the internal extensions
+// package. It exists so that cmd/ and internal/acpserver/ don't both
+// reimplement the same SDK→extension event/subagent conversions.
+package extbridge
+
+import (
+	"context"
+
+	"github.com/mark3labs/kit/internal/extensions"
+	kit "github.com/mark3labs/kit/pkg/kit"
+)
+
+// SDKEventToSubagentEvent converts an SDK [kit.Event] into the
+// extension-facing [extensions.SubagentEvent]. Returns a zero-value event
+// (Type=="") for events that don't map to anything useful — callers should
+// drop those.
+func SDKEventToSubagentEvent(e kit.Event) extensions.SubagentEvent {
+	switch ev := e.(type) {
+	case kit.MessageUpdateEvent:
+		return extensions.SubagentEvent{Type: "text", Content: ev.Chunk}
+	case kit.ReasoningDeltaEvent:
+		return extensions.SubagentEvent{Type: "reasoning", Content: ev.Delta}
+	case kit.ToolCallEvent:
+		return extensions.SubagentEvent{
+			Type: "tool_call", ToolCallID: ev.ToolCallID,
+			ToolName: ev.ToolName, ToolKind: ev.ToolKind, ToolArgs: ev.ToolArgs,
+		}
+	case kit.ToolExecutionStartEvent:
+		return extensions.SubagentEvent{
+			Type: "tool_execution_start", ToolCallID: ev.ToolCallID,
+			ToolName: ev.ToolName, ToolKind: ev.ToolKind,
+		}
+	case kit.ToolExecutionEndEvent:
+		return extensions.SubagentEvent{
+			Type: "tool_execution_end", ToolCallID: ev.ToolCallID,
+			ToolName: ev.ToolName, ToolKind: ev.ToolKind,
+		}
+	case kit.ToolResultEvent:
+		return extensions.SubagentEvent{
+			Type: "tool_result", ToolCallID: ev.ToolCallID,
+			ToolName: ev.ToolName, ToolKind: ev.ToolKind,
+			ToolResult: ev.Result, IsError: ev.IsError,
+		}
+	case kit.TurnStartEvent:
+		return extensions.SubagentEvent{Type: "turn_start"}
+	case kit.TurnEndEvent:
+		return extensions.SubagentEvent{Type: "turn_end"}
+	default:
+		return extensions.SubagentEvent{}
+	}
+}
+
+// SpawnSubagent runs a subagent in-process via the Kit SDK and translates
+// the result/events back into the extension-facing types. The returned
+// handle is always nil — the SDK path runs synchronously and does not
+// expose a separate process handle. Callers that need non-blocking
+// behaviour should run this in their own goroutine.
+//
+// This function consolidates the previously-duplicated wiring in
+// cmd/root.go (interactive + runtime contexts) and
+// internal/acpserver/session.go.
+func SpawnSubagent(ctx context.Context, k *kit.Kit, cfg extensions.SubagentConfig) (*extensions.SubagentHandle, *extensions.SubagentResult, error) {
+	sdkCfg := kit.SubagentConfig{
+		Prompt:       cfg.Prompt,
+		Model:        cfg.Model,
+		SystemPrompt: cfg.SystemPrompt,
+		Timeout:      cfg.Timeout,
+		NoSession:    cfg.NoSession,
+	}
+	if cfg.OnEvent != nil {
+		sdkCfg.OnEvent = func(e kit.Event) {
+			se := SDKEventToSubagentEvent(e)
+			if se.Type != "" {
+				cfg.OnEvent(se)
+			}
+		}
+	}
+
+	result, err := k.Subagent(ctx, sdkCfg)
+	if result == nil {
+		return nil, &extensions.SubagentResult{Error: err}, err
+	}
+
+	extResult := &extensions.SubagentResult{
+		Response:  result.Response,
+		Error:     err,
+		SessionID: result.SessionID,
+		Elapsed:   result.Elapsed,
+	}
+	if result.Usage != nil {
+		extResult.Usage = &extensions.SubagentUsage{
+			InputTokens:  result.Usage.InputTokens,
+			OutputTokens: result.Usage.OutputTokens,
+		}
+	}
+	return nil, extResult, err
+}

internal/extensions/installer.go

@@ -450,25 +450,6 @@ func globalGitInstallRoot() string {
 	return filepath.Join(base, "kit", "git")
 }
 
-// GetInstalledPackages returns all installed packages from both scopes.
-func (i *Installer) GetInstalledPackages() ([]ManifestEntry, error) {
-	var all []ManifestEntry
-
-	global, err := i.loadManifest(ScopeGlobal)
-	if err != nil {
-		return nil, fmt.Errorf("loading global manifest: %w", err)
-	}
-	all = append(all, global.Packages...)
-
-	project, err := i.loadManifest(ScopeProject)
-	if err != nil {
-		return nil, fmt.Errorf("loading project manifest: %w", err)
-	}
-	all = append(all, project.Packages...)
-
-	return all, nil
-}
-
 // IsInstalled checks if a package is installed in either scope.
 // Returns (scope, true) if installed, ("", false) otherwise.
 func (i *Installer) IsInstalled(source *GitSource) (InstallScope, bool) {

internal/extensions/installer_test.go

@@ -245,14 +245,21 @@ func TestManifestEntryIdentity(t *testing.T) {
 	}
 }
 
+// TestLoadAndSaveManifest exercises the live *Installer.loadManifest /
+// saveManifest round-trip against a temp directory, ensuring an absent
+// manifest loads as empty and a saved manifest reads back identically.
 func TestLoadAndSaveManifest(t *testing.T) {
 	tempDir := t.TempDir()
+	installer := &Installer{
+		projectGitRoot: tempDir,
+		globalGitRoot:  tempDir,
+	}
 	manifestPath := filepath.Join(tempDir, "packages.json")
 
 	// Test loading non-existent manifest
-	manifest, err := loadManifestFromPath(manifestPath)
+	manifest, err := installer.loadManifest(ScopeGlobal)
 	if err != nil {
-		t.Fatalf("loadManifestFromPath() error = %v", err)
+		t.Fatalf("loadManifest() error = %v", err)
 	}
 	if len(manifest.Packages) != 0 {
 		t.Errorf("Expected empty packages, got %d", len(manifest.Packages))
@@ -273,15 +280,20 @@ func TestLoadAndSaveManifest(t *testing.T) {
 	}
 
 	// Save it
-	err = saveManifestToPath(manifest, manifestPath)
+	err = installer.saveManifest(manifest, ScopeGlobal)
 	if err != nil {
-		t.Fatalf("saveManifestToPath() error = %v", err)
+		t.Fatalf("saveManifest() error = %v", err)
+	}
+
+	// Verify it was written to expected path
+	if _, err := os.Stat(manifestPath); err != nil {
+		t.Fatalf("manifest file not created: %v", err)
 	}
 
 	// Load it back
-	loaded, err := loadManifestFromPath(manifestPath)
+	loaded, err := installer.loadManifest(ScopeGlobal)
 	if err != nil {
-		t.Fatalf("loadManifestFromPath() error = %v", err)
+		t.Fatalf("loadManifest() error = %v", err)
 	}
 	if len(loaded.Packages) != 1 {
 		t.Errorf("Expected 1 package, got %d", len(loaded.Packages))
@@ -291,21 +303,15 @@ func TestLoadAndSaveManifest(t *testing.T) {
 	}
 }
 
+// TestAddAndRemoveFromManifest verifies that *Installer.addToManifest
+// followed by removeFromManifest leaves the manifest in its original
+// (empty) state, using a temp-directory installer scope.
 func TestAddAndRemoveFromManifest(t *testing.T) {
 	tempDir := t.TempDir()
-
-	// Set up environment for manifest path
-	if err := os.Setenv("XDG_DATA_HOME", tempDir); err != nil {
-		t.Fatalf("Setenv() error = %v", err)
+	installer := &Installer{
+		projectGitRoot: tempDir,
+		globalGitRoot:  tempDir,
 	}
-	defer func() {
-		if err := os.Unsetenv("XDG_DATA_HOME"); err != nil {
-			t.Logf("Unsetenv() error = %v", err)
-		}
-	}()
-
-	// The manifest path when XDG_DATA_HOME is set
-	manifestPath := filepath.Join(tempDir, "kit", "git", "packages.json")
 
 	// Add an entry
 	entry := ManifestEntry{
@@ -315,58 +321,51 @@ func TestAddAndRemoveFromManifest(t *testing.T) {
 		Scope:  ScopeGlobal,
 	}
 
-	err := addEntryToManifest(entry, ScopeGlobal)
-	if err != nil {
-		t.Fatalf("addEntryToManifest() error = %v", err)
+	if err := installer.addToManifest(entry, ScopeGlobal); err != nil {
+		t.Fatalf("addToManifest() error = %v", err)
 	}
 
 	// Verify it was added
-	manifest, err := loadManifestFromPath(manifestPath)
+	manifest, err := installer.loadManifest(ScopeGlobal)
 	if err != nil {
-		t.Fatalf("loadManifestFromPath() error = %v", err)
+		t.Fatalf("loadManifest() error = %v", err)
 	}
 	if len(manifest.Packages) != 1 {
 		t.Errorf("Expected 1 package, got %d", len(manifest.Packages))
 	}
 
 	// Remove it
-	err = removeEntryFromManifest("github.com/user/repo", ScopeGlobal)
-	if err != nil {
-		t.Fatalf("removeEntryFromManifest() error = %v", err)
+	if err := installer.removeFromManifest("github.com/user/repo", ScopeGlobal); err != nil {
+		t.Fatalf("removeFromManifest() error = %v", err)
 	}
 
 	// Verify it was removed
-	manifest, err = loadManifestFromPath(manifestPath)
+	manifest, err = installer.loadManifest(ScopeGlobal)
 	if err != nil {
-		t.Fatalf("loadManifestFromPath() error = %v", err)
+		t.Fatalf("loadManifest() error = %v", err)
 	}
 	if len(manifest.Packages) != 0 {
 		t.Errorf("Expected 0 packages, got %d", len(manifest.Packages))
 	}
 }
 
+// TestFindInManifest writes a manifest file directly to the path
+// resolved by the package-level manifestPathForScope helper and then
+// confirms FindInManifest locates the entry by identity (and returns
+// nil for a non-existent identity).
 func TestFindInManifest(t *testing.T) {
 	tempDir := t.TempDir()
-	if err := os.Setenv("XDG_DATA_HOME", tempDir); err != nil {
-		t.Fatalf("Setenv() error = %v", err)
-	}
-	defer func() {
-		if err := os.Unsetenv("XDG_DATA_HOME"); err != nil {
-			t.Logf("Unsetenv() error = %v", err)
-		}
-	}()
+	t.Setenv("XDG_DATA_HOME", tempDir)
 
-	// Add an entry to global manifest
-	entry := ManifestEntry{
-		Source: "git:github.com/user/repo",
-		Host:   "github.com",
-		Path:   "user/repo",
-		Scope:  ScopeGlobal,
+	// Write a manifest entry directly via the package-level path resolver
+	// so FindInManifest (which uses manifestPathForScope) can read it back.
+	manifestPath := manifestPathForScope(ScopeGlobal)
+	if err := os.MkdirAll(filepath.Dir(manifestPath), 0755); err != nil {
+		t.Fatalf("MkdirAll() error = %v", err)
 	}
-
-	err := addEntryToManifest(entry, ScopeGlobal)
-	if err != nil {
-		t.Fatalf("addEntryToManifest() error = %v", err)
+	data := []byte(`{"packages":[{"source":"git:github.com/user/repo","repo":"","host":"github.com","path":"user/repo","pinned":false,"scope":"global","installed":"0001-01-01T00:00:00Z"}]}`)
+	if err := os.WriteFile(manifestPath, data, 0644); err != nil {
+		t.Fatalf("WriteFile() error = %v", err)
 	}
 
 	// Find it

internal/extensions/manifest.go

@@ -72,30 +72,6 @@ func loadManifestFromPath(path string) (*Manifest, error) {
 	return &manifest, nil
 }
 
-// saveManifestToScope saves the manifest to the given scope.
-func saveManifestToScope(manifest *Manifest, scope InstallScope) error {
-	path := manifestPathForScope(scope)
-	return saveManifestToPath(manifest, path)
-}
-
-// saveManifestToPath saves a manifest to a specific file path.
-func saveManifestToPath(manifest *Manifest, path string) error {
-	if err := os.MkdirAll(filepath.Dir(path), 0755); err != nil {
-		return fmt.Errorf("creating manifest directory: %w", err)
-	}
-
-	data, err := json.MarshalIndent(manifest, "", "  ")
-	if err != nil {
-		return fmt.Errorf("encoding manifest: %w", err)
-	}
-
-	if err := os.WriteFile(path, data, 0644); err != nil {
-		return fmt.Errorf("writing manifest: %w", err)
-	}
-
-	return nil
-}
-
 // manifestPathForScope returns the manifest file path for a scope.
 func manifestPathForScope(scope InstallScope) string {
 	if scope == ScopeProject {
@@ -113,55 +89,6 @@ func manifestPathForScope(scope InstallScope) string {
 	return filepath.Join(base, "kit", "git", "packages.json")
 }
 
-// GetGlobalManifest returns the global manifest.
-func GetGlobalManifest() (*Manifest, error) {
-	return loadManifestFromScope(ScopeGlobal)
-}
-
-// GetProjectManifest returns the project manifest.
-func GetProjectManifest() (*Manifest, error) {
-	return loadManifestFromScope(ScopeProject)
-}
-
-// addEntryToManifest adds or replaces an entry in the manifest for a scope.
-func addEntryToManifest(entry ManifestEntry, scope InstallScope) error {
-	manifest, err := loadManifestFromScope(scope)
-	if err != nil {
-		return err
-	}
-
-	// Remove any existing entry with same identity
-	identity := entry.Identity()
-	filtered := make([]ManifestEntry, 0, len(manifest.Packages))
-	for _, p := range manifest.Packages {
-		if p.Identity() != identity {
-			filtered = append(filtered, p)
-		}
-	}
-	filtered = append(filtered, entry)
-	manifest.Packages = filtered
-
-	return saveManifestToScope(manifest, scope)
-}
-
-// removeEntryFromManifest removes an entry by identity from the manifest for a scope.
-func removeEntryFromManifest(identity string, scope InstallScope) error {
-	manifest, err := loadManifestFromScope(scope)
-	if err != nil {
-		return err
-	}
-
-	filtered := make([]ManifestEntry, 0, len(manifest.Packages))
-	for _, p := range manifest.Packages {
-		if p.Identity() != identity {
-			filtered = append(filtered, p)
-		}
-	}
-	manifest.Packages = filtered
-
-	return saveManifestToScope(manifest, scope)
-}
-
 // FindInManifest finds an entry by identity in either global or project manifest.
 // Returns the entry and its scope, or nil if not found.
 func FindInManifest(identity string) (*ManifestEntry, InstallScope, error) {

internal/extensions/subagent.go

@@ -2,22 +2,15 @@
 package extensions
 
 import (
-	"bufio"
-	"context"
-	"encoding/json"
 	"fmt"
 	"os"
-	"os/exec"
-	"strings"
 	"sync"
-	"sync/atomic"
 	"time"
 )
 
 // ---------------------------------------------------------------------------
 // Subagent types
 // ---------------------------------------------------------------------------
-
 // SubagentConfig configures a subagent spawn.
 type SubagentConfig struct {
 	// Prompt is the task/instruction for the subagent (required).
@@ -157,221 +150,3 @@ func (h *SubagentHandle) Wait() SubagentResult {
 func (h *SubagentHandle) Done() <-chan struct{} {
 	return h.done
 }
-
-// ---------------------------------------------------------------------------
-// Internal helpers
-// ---------------------------------------------------------------------------
-
-// subagentJSONOutput matches the JSON envelope produced by `kit --json`.
-type subagentJSONOutput struct {
-	Response   string `json:"response"`
-	StopReason string `json:"stop_reason,omitempty"`
-	SessionID  string `json:"session_id,omitempty"`
-	Usage      *struct {
-		InputTokens  int64 `json:"input_tokens"`
-		OutputTokens int64 `json:"output_tokens"`
-	} `json:"usage,omitempty"`
-}
-
-var subagentCounter atomic.Uint64
-
-func generateSubagentID() string {
-	n := subagentCounter.Add(1)
-	return fmt.Sprintf("sub-%d-%d", time.Now().UnixNano(), n)
-}
-
-func findKitBinary() string {
-	// Try the current process executable first.
-	if exe, err := os.Executable(); err == nil {
-		if _, err := os.Stat(exe); err == nil {
-			return exe
-		}
-	}
-	// Fall back to PATH lookup.
-	if p, err := exec.LookPath("kit"); err == nil {
-		return p
-	}
-	return "kit"
-}
-
-// ---------------------------------------------------------------------------
-// SpawnSubagent implementation
-// ---------------------------------------------------------------------------
-
-// SpawnSubagent spawns a child Kit instance to perform a task.
-//
-// When config.Blocking is true, blocks until completion and returns the result
-// directly (handle is nil). When false, returns immediately with a handle for
-// monitoring/cancellation.
-//
-// The subagent runs with --json --no-session --no-extensions flags by default,
-// ensuring isolation from the parent's extensions and session state.
-func SpawnSubagent(cfg SubagentConfig) (*SubagentHandle, *SubagentResult, error) {
-	if cfg.Prompt == "" {
-		return nil, nil, fmt.Errorf("prompt is required")
-	}
-
-	timeout := cfg.Timeout
-	if timeout == 0 {
-		timeout = 5 * time.Minute
-	}
-
-	kitBinary := findKitBinary()
-
-	// Build subprocess arguments.
-	args := []string{
-		"--json",
-		"--no-extensions",
-	}
-	if cfg.NoSession {
-		args = append(args, "--no-session")
-	}
-	if cfg.Model != "" {
-		args = append(args, "--model", cfg.Model)
-	}
-
-	// Handle system prompt - write to temp file if provided.
-	var tmpFile *os.File
-	if cfg.SystemPrompt != "" {
-		var err error
-		tmpFile, err = os.CreateTemp("", "kit-subagent-*.txt")
-		if err != nil {
-			return nil, nil, fmt.Errorf("create temp file: %w", err)
-		}
-		if _, err := tmpFile.WriteString(cfg.SystemPrompt); err != nil {
-			_ = tmpFile.Close()
-			_ = os.Remove(tmpFile.Name())
-			return nil, nil, fmt.Errorf("write system prompt: %w", err)
-		}
-		_ = tmpFile.Close()
-		args = append(args, "--system-prompt", tmpFile.Name())
-	}
-
-	// Add the prompt as a positional argument.
-	args = append(args, cfg.Prompt)
-
-	// Create command with timeout context.
-	ctx, cancel := context.WithTimeout(context.Background(), timeout)
-
-	cmd := exec.CommandContext(ctx, kitBinary, args...)
-	cmd.Env = os.Environ()
-
-	stdout, err := cmd.StdoutPipe()
-	if err != nil {
-		cancel()
-		if tmpFile != nil {
-			_ = os.Remove(tmpFile.Name())
-		}
-		return nil, nil, fmt.Errorf("stdout pipe: %w", err)
-	}
-	stderr, err := cmd.StderrPipe()
-	if err != nil {
-		cancel()
-		if tmpFile != nil {
-			_ = os.Remove(tmpFile.Name())
-		}
-		return nil, nil, fmt.Errorf("stderr pipe: %w", err)
-	}
-
-	handle := &SubagentHandle{
-		ID:   generateSubagentID(),
-		done: make(chan struct{}),
-	}
-
-	// Start the subprocess.
-	start := time.Now()
-	if err := cmd.Start(); err != nil {
-		cancel()
-		if tmpFile != nil {
-			_ = os.Remove(tmpFile.Name())
-		}
-		return nil, nil, fmt.Errorf("start subprocess: %w", err)
-	}
-
-	handle.mu.Lock()
-	handle.proc = cmd.Process
-	handle.mu.Unlock()
-
-	// Run the subprocess monitoring in a goroutine.
-	go func() {
-		defer close(handle.done)
-		defer cancel()
-		if tmpFile != nil {
-			defer func() { _ = os.Remove(tmpFile.Name()) }()
-		}
-
-		var wg sync.WaitGroup
-		var stdoutBuf strings.Builder
-
-		// Read stderr (live output).
-		wg.Go(func() {
-			scanner := bufio.NewScanner(stderr)
-			scanner.Buffer(make([]byte, 256*1024), 256*1024)
-			for scanner.Scan() {
-				line := scanner.Text()
-				if cfg.OnOutput != nil && strings.TrimSpace(line) != "" {
-					cfg.OnOutput(line + "\n")
-				}
-			}
-		})
-
-		// Read stdout (JSON output).
-		scanner := bufio.NewScanner(stdout)
-		scanner.Buffer(make([]byte, 256*1024), 256*1024)
-		for scanner.Scan() {
-			stdoutBuf.WriteString(scanner.Text() + "\n")
-		}
-
-		wg.Wait()
-		waitErr := cmd.Wait()
-		elapsed := time.Since(start)
-
-		// Build result.
-		result := SubagentResult{Elapsed: elapsed}
-		if waitErr != nil {
-			result.Error = waitErr
-			if exitErr, ok := waitErr.(*exec.ExitError); ok {
-				result.ExitCode = exitErr.ExitCode()
-			} else {
-				result.ExitCode = 1
-			}
-		}
-
-		// Parse JSON output.
-		raw := strings.TrimSpace(stdoutBuf.String())
-		var parsed subagentJSONOutput
-		if raw != "" && json.Unmarshal([]byte(raw), &parsed) == nil {
-			result.Response = parsed.Response
-			result.SessionID = parsed.SessionID
-			if parsed.Usage != nil {
-				result.Usage = &SubagentUsage{
-					InputTokens:  parsed.Usage.InputTokens,
-					OutputTokens: parsed.Usage.OutputTokens,
-				}
-			}
-		} else {
-			// Fallback: use raw stdout.
-			result.Response = raw
-		}
-
-		handle.mu.Lock()
-		handle.result = &result
-		handle.proc = nil
-		handle.mu.Unlock()
-
-		if cfg.OnComplete != nil {
-			cfg.OnComplete(result)
-		}
-	}()
-
-	if cfg.Blocking {
-		// Wait for completion and return result directly.
-		<-handle.done
-		handle.mu.Lock()
-		r := handle.result
-		handle.mu.Unlock()
-		return nil, r, nil
-	}
-
-	return handle, nil, nil
-}

internal/kitsetup/setup.go

@@ -72,6 +72,9 @@ type AgentSetupOptions struct {
 	// OnMCPServerLoaded, if non-nil, is called when each MCP server finishes
 	// loading (successfully or with error). Called from the background goroutine.
 	OnMCPServerLoaded func(serverName string, toolCount int, err error)
+	// MCPTaskConfig configures task-augmented tools/call execution. The
+	// zero value preserves historical synchronous-only behaviour.
+	MCPTaskConfig tools.MCPTaskConfig
 }
 
 // AgentSetupResult bundles the created agent and any debug logger so the caller
@@ -229,6 +232,7 @@ func SetupAgent(ctx context.Context, opts AgentSetupOptions) (*AgentSetupResult,
 		ToolWrapper:       toolWrapper,
 		ExtraTools:        extraTools,
 		OnMCPServerLoaded: opts.OnMCPServerLoaded,
+		MCPTaskConfig:     opts.MCPTaskConfig,
 	})
 	if err != nil {
 		return nil, fmt.Errorf("failed to create agent: %w", err)

internal/models/cache_options.go

@@ -3,7 +3,6 @@ package models
 import (
 	"crypto/sha256"
 	"encoding/hex"
-	"maps"
 	"os"
 
 	"charm.land/fantasy"
@@ -69,19 +68,3 @@ func generateCacheKey(systemPrompt, modelID string) string {
 	// Prefix with "kit-" to identify KIT-generated cache keys
 	return "kit-" + hex.EncodeToString(h.Sum(nil))[:24]
 }
-
-// mergeProviderOptions merges multiple ProviderOptions maps.
-// Later maps take precedence over earlier ones.
-func mergeProviderOptions(opts ...fantasy.ProviderOptions) fantasy.ProviderOptions {
-	result := make(fantasy.ProviderOptions)
-
-	for _, opt := range opts {
-		maps.Copy(result, opt)
-	}
-
-	if len(result) == 0 {
-		return nil
-	}
-
-	return result
-}

internal/models/cache_options_test.go

@@ -3,8 +3,6 @@ package models
 import (
 	"os"
 	"testing"
-
-	"charm.land/fantasy"
 )
 
 func TestModelInfo_SupportsCaching(t *testing.T) {
@@ -192,57 +190,3 @@ func TestCachingPriorityOverThinking(t *testing.T) {
 		t.Errorf("OpenAI caching should work when thinking is OFF")
 	}
 }
-
-func TestMergeProviderOptions(t *testing.T) {
-	opts1 := fantasy.ProviderOptions{
-		"provider1": &testProviderData{value: "value1"},
-	}
-	opts2 := fantasy.ProviderOptions{
-		"provider2": &testProviderData{value: "value2"},
-	}
-
-	merged := mergeProviderOptions(opts1, opts2)
-
-	if len(merged) != 2 {
-		t.Errorf("mergeProviderOptions should combine options from multiple maps, got %d items", len(merged))
-	}
-
-	if _, ok := merged["provider1"]; !ok {
-		t.Errorf("merged options should contain 'provider1' key")
-	}
-
-	if _, ok := merged["provider2"]; !ok {
-		t.Errorf("merged options should contain 'provider2' key")
-	}
-
-	// Later options should override earlier ones
-	opts3 := fantasy.ProviderOptions{
-		"provider1": &testProviderData{value: "overridden"},
-	}
-	merged2 := mergeProviderOptions(opts1, opts3)
-
-	if data, ok := merged2["provider1"].(*testProviderData); ok {
-		if data.value != "overridden" {
-			t.Errorf("later options should override earlier ones, got %q", data.value)
-		}
-	}
-
-	if mergeProviderOptions() != nil {
-		t.Errorf("mergeProviderOptions with no args should return nil")
-	}
-}
-
-// testProviderData is a simple implementation of ProviderOptionsData for testing
-type testProviderData struct {
-	value string
-}
-
-func (t *testProviderData) Options() {}
-
-func (t *testProviderData) MarshalJSON() ([]byte, error) {
-	return []byte(`"` + t.value + `"`), nil
-}
-
-func (t *testProviderData) UnmarshalJSON(data []byte) error {
-	return nil
-}

internal/models/pool.go

@@ -1,168 +0,0 @@
-package models
-
-import (
-	"context"
-	"sync"
-	"time"
-
-	"charm.land/fantasy"
-)
-
-// ProviderPool manages reusable LLM provider instances to reduce overhead
-// when spawning multiple subagents or making repeated completion calls.
-type ProviderPool struct {
-	mu        sync.RWMutex
-	providers map[string]*pooledProvider
-	ttl       time.Duration
-	closed    bool
-	closeCh   chan struct{}
-}
-
-type pooledProvider struct {
-	model        fantasy.LanguageModel
-	closer       func() error
-	providerOpts fantasy.ProviderOptions
-	created      time.Time
-	lastUsed     time.Time
-	refs         int32
-}
-
-// DefaultPoolTTL is the default time-to-live for idle pooled providers.
-const DefaultPoolTTL = 5 * time.Minute
-
-// globalPool is the singleton provider pool instance.
-var globalPool *ProviderPool
-var poolOnce sync.Once
-
-// GetGlobalPool returns the singleton provider pool instance.
-func GetGlobalPool() *ProviderPool {
-	poolOnce.Do(func() {
-		globalPool = NewProviderPool(DefaultPoolTTL)
-	})
-	return globalPool
-}
-
-// NewProviderPool creates a provider pool with the given TTL for idle providers.
-func NewProviderPool(ttl time.Duration) *ProviderPool {
-	p := &ProviderPool{
-		providers: make(map[string]*pooledProvider),
-		ttl:       ttl,
-		closeCh:   make(chan struct{}),
-	}
-	go p.cleanupLoop()
-	return p
-}
-
-// Get returns a provider for the model string, creating one if needed.
-// The returned release function must be called when the provider is no longer
-// needed. The provider may be reused by subsequent Get calls.
-func (p *ProviderPool) Get(ctx context.Context, modelString string) (fantasy.LanguageModel, fantasy.ProviderOptions, func(), error) {
-	p.mu.Lock()
-
-	// Check if we have an existing provider.
-	if pp, ok := p.providers[modelString]; ok {
-		pp.refs++
-		pp.lastUsed = time.Now()
-		p.mu.Unlock()
-		return pp.model, pp.providerOpts, func() { p.release(modelString) }, nil
-	}
-
-	p.mu.Unlock()
-
-	// Create a new provider outside the lock.
-	config := &ProviderConfig{ModelString: modelString}
-	result, err := CreateProvider(ctx, config)
-	if err != nil {
-		return nil, nil, nil, err
-	}
-
-	p.mu.Lock()
-	defer p.mu.Unlock()
-
-	// Double-check: another goroutine may have created one while we were unlocked.
-	if pp, ok := p.providers[modelString]; ok {
-		// Close the one we just created and use the existing one.
-		if result.Closer != nil {
-			_ = result.Closer.Close()
-		}
-		pp.refs++
-		pp.lastUsed = time.Now()
-		return pp.model, pp.providerOpts, func() { p.release(modelString) }, nil
-	}
-
-	var closerFn func() error
-	if result.Closer != nil {
-		closerFn = result.Closer.Close
-	}
-
-	pp := &pooledProvider{
-		model:        result.Model,
-		closer:       closerFn,
-		providerOpts: result.ProviderOptions,
-		created:      time.Now(),
-		lastUsed:     time.Now(),
-		refs:         1,
-	}
-	p.providers[modelString] = pp
-
-	return pp.model, pp.providerOpts, func() { p.release(modelString) }, nil
-}
-
-func (p *ProviderPool) release(modelString string) {
-	p.mu.Lock()
-	defer p.mu.Unlock()
-
-	if pp, ok := p.providers[modelString]; ok {
-		pp.refs--
-		pp.lastUsed = time.Now()
-	}
-}
-
-func (p *ProviderPool) cleanupLoop() {
-	ticker := time.NewTicker(p.ttl / 2)
-	defer ticker.Stop()
-
-	for {
-		select {
-		case <-p.closeCh:
-			return
-		case <-ticker.C:
-			p.cleanup()
-		}
-	}
-}
-
-func (p *ProviderPool) cleanup() {
-	p.mu.Lock()
-	defer p.mu.Unlock()
-
-	now := time.Now()
-	for key, pp := range p.providers {
-		// Only clean up providers with no active references and past TTL.
-		if pp.refs <= 0 && now.Sub(pp.lastUsed) > p.ttl {
-			if pp.closer != nil {
-				_ = pp.closer()
-			}
-			delete(p.providers, key)
-		}
-	}
-}
-
-// Close shuts down the pool and releases all providers.
-func (p *ProviderPool) Close() {
-	p.mu.Lock()
-	if p.closed {
-		p.mu.Unlock()
-		return
-	}
-	p.closed = true
-	close(p.closeCh)
-
-	for key, pp := range p.providers {
-		if pp.closer != nil {
-			_ = pp.closer()
-		}
-		delete(p.providers, key)
-	}
-	p.mu.Unlock()
-}

internal/models/registry.go

@@ -4,6 +4,7 @@ import (
 	_ "embed"
 	"encoding/json"
 	"fmt"
+	"maps"
 	"os"
 	"strings"
 
@@ -111,13 +112,30 @@ func NewModelsRegistry() *ModelsRegistry {
 }
 
 // buildFromModelsDB converts models.dev provider data into our internal format.
-// It tries the on-disk cache first and falls back to the embedded database.
+// It starts from the compile-time embedded database and merges on-disk cached
+// data from `kit update-models` on top. Cached provider metadata replaces
+// embedded metadata, and model entries are merged with cached models taking
+// precedence. This means newly synced models are available while embedded
+// models that haven't been synced yet are still reachable.
 func buildFromModelsDB() map[string]ProviderInfo {
-	// Try cached data first (from `kit update-models`)
-	dbProviders, _ := LoadCachedProviders()
-	if len(dbProviders) == 0 {
-		// Fall back to compile-time embedded data
-		dbProviders = loadEmbeddedProviders()
+	// Start with compile-time embedded data as the base.
+	dbProviders := loadEmbeddedProviders()
+	if dbProviders == nil {
+		dbProviders = make(ModelsDBProviders)
+	}
+
+	// Merge on-disk cached data on top (cached takes precedence).
+	if cached, _ := LoadCachedProviders(); len(cached) > 0 {
+		for providerID, cp := range cached {
+			if existing, ok := dbProviders[providerID]; ok {
+				// Merge models: embedded base + cached overrides.
+				mergedModels := make(map[string]modelsDBModel, len(existing.Models)+len(cp.Models))
+				maps.Copy(mergedModels, existing.Models)
+				maps.Copy(mergedModels, cp.Models)
+				cp.Models = mergedModels
+			}
+			dbProviders[providerID] = cp
+		}
 	}
 
 	providers := make(map[string]ProviderInfo, len(dbProviders))

internal/prompts/loader.go

@@ -36,15 +36,17 @@ type Diagnostic struct {
 }
 
 // LoadAll discovers and loads all prompt templates from standard locations
-// and any extra paths. Templates are loaded in order of precedence (lowest
-// to highest), with later templates overriding earlier ones of the same name.
+// and any extra paths. Templates are loaded in order of precedence (highest
+// to lowest); the first source to define a given name wins, later definitions
+// of the same name are dropped with a diagnostic.
 //
 // Discovery paths searched in order:
 //  1. Default templates (if IncludeDefaults)
-//  2. ~/.kit/prompts/ (global user templates)
-//  3. .kit/prompts/ (project-local templates)
-//  4. ConfigPaths (from configuration)
-//  5. ExtraPaths (explicit paths, highest precedence)
+//  2. ~/.kit/prompts/                          (legacy global)
+//  3. $XDG_CONFIG_HOME/kit/prompts/            (XDG global, default ~/.config/kit/prompts/)
+//  4. <cwd>/.kit/prompts/                      (project-local templates)
+//  5. ConfigPaths                              (from configuration)
+//  6. ExtraPaths                               (explicit paths, lowest precedence)
 func LoadAll(opts LoadOptions) ([]*PromptTemplate, []Diagnostic, error) {
 	if opts.Cwd == "" {
 		opts.Cwd, _ = os.Getwd()
@@ -88,13 +90,21 @@ func LoadAll(opts LoadOptions) ([]*PromptTemplate, []Diagnostic, error) {
 		addTemplates(defaults, "default")
 	}
 
-	// 2. Global user templates: ~/.kit/prompts/
-	globalDir := filepath.Join(opts.HomeDir, ".kit", "prompts")
-	if templates, err := LoadFromDir(globalDir); err == nil {
+	// 2. Legacy global user templates: ~/.kit/prompts/
+	legacyGlobalDir := filepath.Join(opts.HomeDir, ".kit", "prompts")
+	if templates, err := LoadFromDir(legacyGlobalDir); err == nil {
 		addTemplates(templates, "global")
 	}
 
-	// 3. Project-local templates: .kit/prompts/
+	// 3. XDG global user templates: $XDG_CONFIG_HOME/kit/prompts/
+	//    Default: ~/.config/kit/prompts/. Aligns with extensions and skills.
+	if xdgDir := GlobalDir(); xdgDir != "" && xdgDir != legacyGlobalDir {
+		if templates, err := LoadFromDir(xdgDir); err == nil {
+			addTemplates(templates, "global")
+		}
+	}
+
+	// 4. Project-local templates: .kit/prompts/
 	localDir := filepath.Join(opts.Cwd, ".kit", "prompts")
 	if templates, err := LoadFromDir(localDir); err == nil {
 		addTemplates(templates, "local")
@@ -179,31 +189,6 @@ func LoadFromDir(dir string) ([]*PromptTemplate, error) {
 	return templates, nil
 }
 
-// Deduplicate removes duplicate templates by name, keeping the first occurrence.
-// It returns the deduplicated list and diagnostics for any collisions.
-// This is a standalone function for when you need to deduplicate an existing list.
-func Deduplicate(templates []*PromptTemplate) ([]*PromptTemplate, []Diagnostic) {
-	seen := make(map[string]*PromptTemplate)
-	var result []*PromptTemplate
-	var diagnostics []Diagnostic
-
-	for _, tpl := range templates {
-		if existing, ok := seen[tpl.Name]; ok {
-			diagnostics = append(diagnostics, Diagnostic{
-				Name:        tpl.Name,
-				KeptPath:    existing.FilePath,
-				DroppedPath: tpl.FilePath,
-				Reason:      "duplicate template name (first-match-wins)",
-			})
-		} else {
-			seen[tpl.Name] = tpl
-			result = append(result, tpl)
-		}
-	}
-
-	return result, diagnostics
-}
-
 // loadDefaultTemplates returns the built-in default templates.
 // These are embedded templates that ship with Kit.
 func loadDefaultTemplates() []*PromptTemplate {
@@ -211,3 +196,22 @@ func loadDefaultTemplates() []*PromptTemplate {
 	// For now, return an empty slice - users can define their own templates
 	return nil
 }
+
+// GlobalDir returns the XDG-aligned global prompts directory, respecting
+// $XDG_CONFIG_HOME. Defaults to ~/.config/kit/prompts/. Returns an empty
+// string if the user's home directory cannot be resolved.
+//
+// This is the canonical location for user-wide prompt templates and aligns
+// with the discovery paths used for extensions ($XDG_CONFIG_HOME/kit/extensions/)
+// and skills ($XDG_CONFIG_HOME/kit/skills/).
+func GlobalDir() string {
+	base := os.Getenv("XDG_CONFIG_HOME")
+	if base == "" {
+		home, err := os.UserHomeDir()
+		if err != nil {
+			return ""
+		}
+		base = filepath.Join(home, ".config")
+	}
+	return filepath.Join(base, "kit", "prompts")
+}

internal/session/compaction_test.go

@@ -129,26 +129,35 @@ func TestCompactionWithNewMessagesAfterCompaction(t *testing.T) {
 	msg4 := message.Message{Role: message.RoleAssistant, Parts: []message.ContentPart{message.TextContent{Text: "Message 4 - after compaction"}}}
 	_, _ = tm.AppendMessage(msg4)
 
-	// BuildContext should return: [summary] + [M4 (new after compaction)] + [M3 (kept)]
+	// BuildContext should return: [summary] + [M3 (kept)] + [M4 (new after compaction)]
+	// Kept messages must appear BEFORE post-compaction messages so the LLM
+	// sees the conversation in chronological order. Otherwise the latest
+	// post-compaction user message would be followed by an older kept user
+	// message, breaking user/assistant alternation and causing the model to
+	// respond as if the post-compaction turn never happened.
 	messages, _, _ := tm.BuildContext()
 	if len(messages) != 3 {
-		t.Fatalf("expected 3 messages (summary + M4 + M3), got %d: %+v", len(messages), messages)
+		t.Fatalf("expected 3 messages (summary + M3 + M4), got %d: %+v", len(messages), messages)
 	}
 
-	// Verify order: summary, M4 (new), M3 (kept)
+	// Verify order: summary, M3 (kept), M4 (new)
 	if messages[0].Role != fantasy.MessageRoleSystem {
 		t.Errorf("first message should be summary, got %s", messages[0].Role)
 	}
-	if messages[1].Role != fantasy.MessageRoleAssistant {
-		t.Errorf("second message should be assistant (M4), got %s", messages[1].Role)
+	if messages[1].Role != fantasy.MessageRoleUser {
+		t.Errorf("second message should be user (M3 kept), got %s", messages[1].Role)
 	}
-	m4Text := messages[1].Content[0].(fantasy.TextPart).Text
+	m3Text := messages[1].Content[0].(fantasy.TextPart).Text
+	if m3Text != "Message 3 - kept" {
+		t.Errorf("unexpected M3 text: %s", m3Text)
+	}
+	if messages[2].Role != fantasy.MessageRoleAssistant {
+		t.Errorf("third message should be assistant (M4 post-compact), got %s", messages[2].Role)
+	}
+	m4Text := messages[2].Content[0].(fantasy.TextPart).Text
 	if m4Text != "Message 4 - after compaction" {
 		t.Errorf("unexpected M4 text: %s", m4Text)
 	}
-	if messages[2].Role != fantasy.MessageRoleUser {
-		t.Errorf("third message should be user (M3), got %s", messages[2].Role)
-	}
 
 	// Verify that M1 is NOT in the context
 	for i, msg := range messages {

internal/session/session_dir_test.go

@@ -0,0 +1,70 @@
+package session
+
+import (
+	"strings"
+	"testing"
+)
+
+// TestEncodeCwdForDir verifies the working-directory → session-directory
+// name encoding strips characters that are illegal on Windows (notably the
+// drive-letter colon, see issue #18) while preserving the previous output
+// for the typical Unix paths.
+func TestEncodeCwdForDir(t *testing.T) {
+	tests := []struct {
+		name string
+		cwd  string
+		want string
+	}{
+		{
+			name: "unix absolute path",
+			cwd:  "/home/user/proj",
+			want: "home--user--proj",
+		},
+		{
+			name: "unix relative path",
+			cwd:  "proj/sub",
+			want: "proj--sub",
+		},
+		{
+			name: "windows drive root",
+			cwd:  `C:\test`,
+			want: "C--test",
+		},
+		{
+			name: "windows nested path",
+			cwd:  `C:\Users\User\code`,
+			want: "C--Users--User--code",
+		},
+		{
+			name: "windows secondary drive",
+			cwd:  `S:\work\repo`,
+			want: "S--work--repo",
+		},
+		{
+			name: "windows mixed separators",
+			cwd:  `C:\Users/User\code`,
+			want: "C--Users--User--code",
+		},
+		{
+			name: "windows other illegal chars stripped",
+			cwd:  `C:\a<b>c|d?e*f"g`,
+			want: "C--abcdefg",
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			got := encodeCwdForDir(tc.cwd)
+			if got != tc.want {
+				t.Errorf("encodeCwdForDir(%q) = %q, want %q", tc.cwd, got, tc.want)
+			}
+			// Encoded directory must never contain characters that are
+			// illegal in Windows directory names.
+			for _, bad := range []string{":", "<", ">", "\"", "|", "?", "*", "\\", "/"} {
+				if strings.Contains(got, bad) {
+					t.Errorf("encodeCwdForDir(%q) = %q contains illegal char %q", tc.cwd, got, bad)
+				}
+			}
+		})
+	}
+}

internal/session/store.go

@@ -6,8 +6,10 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"runtime"
 	"sort"
 	"strings"
+	"sync"
 	"time"
 )
 
@@ -97,6 +99,11 @@ func ListAllSessions() ([]SessionInfo, error) {
 
 // listSessionsInDir reads all .jsonl files in a directory and extracts session info.
 // Empty sessions (no messages) are automatically cleaned up and not returned.
+//
+// Per-file extraction is parallelized across a small worker pool because each
+// file requires a full JSONL scan to compute MessageCount and FirstMessage —
+// for users with many sessions this is the dominant cost of opening the
+// session picker.
 func listSessionsInDir(dir string) ([]SessionInfo, error) {
 	if _, err := os.Stat(dir); os.IsNotExist(err) {
 		return nil, nil
@@ -107,20 +114,47 @@ func listSessionsInDir(dir string) ([]SessionInfo, error) {
 		return nil, fmt.Errorf("failed to read directory %s: %w", dir, err)
 	}
 
-	var sessions []SessionInfo
+	// Collect candidate paths first so we can parallelize the heavy work.
+	paths := make([]string, 0, len(entries))
 	for _, entry := range entries {
 		if entry.IsDir() || !strings.HasSuffix(entry.Name(), ".jsonl") {
 			continue
 		}
+		paths = append(paths, filepath.Join(dir, entry.Name()))
+	}
 
-		path := filepath.Join(dir, entry.Name())
-		info, err := extractSessionInfo(path)
-		if err != nil {
-			continue // skip malformed session files
+	results := make([]*SessionInfo, len(paths))
+
+	// Worker pool sized to GOMAXPROCS, capped to avoid thrashing for tiny lists.
+	workers := max(min(runtime.GOMAXPROCS(0), len(paths)), 1)
+
+	var wg sync.WaitGroup
+	jobs := make(chan int, len(paths))
+	for range workers {
+		wg.Go(func() {
+			for i := range jobs {
+				info, err := extractSessionInfo(paths[i])
+				if err != nil {
+					continue // skip malformed session files
+				}
+				results[i] = info
+			}
+		})
+	}
+	for i := range paths {
+		jobs <- i
+	}
+	close(jobs)
+	wg.Wait()
+
+	sessions := make([]SessionInfo, 0, len(results))
+	for i, info := range results {
+		if info == nil {
+			continue
 		}
-		// Clean up and skip empty sessions (no messages)
+		// Clean up and skip empty sessions (no messages).
 		if info.MessageCount == 0 {
-			_ = os.Remove(path)
+			_ = os.Remove(paths[i])
 			continue
 		}
 		sessions = append(sessions, *info)

internal/session/tree_manager.go

@@ -755,9 +755,17 @@ func (tm *TreeManager) BuildContext() (messages []fantasy.Message, provider stri
 		}
 	}
 
-	// If there is a compaction, inject the summary first and collect
-	// the kept messages starting from FirstKeptEntryID (since the
-	// compaction entry's parent chain doesn't include them).
+	// If there is a compaction, inject the summary first, then the
+	// preserved "kept" messages (chronologically before the compaction),
+	// then the post-compaction messages (chronologically after).
+	//
+	// Order matters: the kept messages must come BEFORE the post-compaction
+	// branch so the LLM sees the conversation in chronological order. If the
+	// kept messages were appended last, the latest user message in the
+	// current branch would be followed by an older kept user message,
+	// breaking the strict user/assistant alternation that providers expect
+	// and causing the model to respond as if the previous turn never
+	// happened.
 	if lastCompaction != nil {
 		messages = append(messages, fantasy.Message{
 			Role: fantasy.MessageRoleSystem,
@@ -768,49 +776,10 @@ func (tm *TreeManager) BuildContext() (messages []fantasy.Message, provider stri
 			},
 		})
 
-		// Collect entries from the compaction entry itself (at compactionIndex)
-		// and any entries before it in the branch (newer messages).
-		for i := compactionIndex; i < len(branch); i++ {
-			entry := branch[i]
-			switch e := entry.(type) {
-			case *MessageEntry:
-				msg, err := e.ToMessage()
-				if err != nil {
-					continue // skip malformed entries
-				}
-				msgs := msg.ToLLMMessages()
-				messages = append(messages, msgs...)
-
-			case *BranchSummaryEntry:
-				// Convert branch summary to a user message for context.
-				if e.Summary != "" {
-					messages = append(messages, fantasy.Message{
-						Role: fantasy.MessageRoleUser,
-						Content: []fantasy.MessagePart{
-							fantasy.TextPart{
-								Text: fmt.Sprintf("[Branch context: %s]", e.Summary),
-							},
-						},
-					})
-				}
-
-			case *ModelChangeEntry:
-				provider = e.Provider
-				modelID = e.ModelID
-
-			case *CompactionEntry:
-				// Already handled above (summary injected).
-				continue
-			}
-		}
-
-		// Now collect the kept messages starting from FirstKeptEntryID.
-		// These are not in the current branch because the compaction entry
-		// is parented to the first kept entry's parent, not the first kept entry.
-		// We iterate through entries in order (not using getBranchLocked) to avoid
-		// walking back to old compacted messages.
-		// We stop when we reach the compaction entry to avoid double-counting
-		// messages that were added after the compaction.
+		// Step 1: collect the kept messages starting from FirstKeptEntryID.
+		// These are not on the current branch (the compaction entry is a
+		// new root with no parent), so we iterate tm.entries in append order
+		// and stop when we reach the compaction entry itself.
 		if lastCompaction.FirstKeptEntryID != "" {
 			found := false
 			for _, entry := range tm.entries {
@@ -825,13 +794,12 @@ func (tm *TreeManager) BuildContext() (messages []fantasy.Message, provider stri
 					}
 				}
 
-				// Stop when we reach the compaction entry itself.
-				// Messages after the compaction are collected from the branch walk above.
+				// Stop when we reach the compaction entry itself; messages
+				// after it are collected from the branch walk below.
 				if entryID == lastCompaction.ID {
 					break
 				}
 
-				// Process this kept entry.
 				switch e := entry.(type) {
 				case *MessageEntry:
 					msg, err := e.ToMessage()
@@ -860,6 +828,42 @@ func (tm *TreeManager) BuildContext() (messages []fantasy.Message, provider stri
 			}
 		}
 
+		// Step 2: collect entries on the current branch after the compaction
+		// entry (these are post-compaction messages). The compaction entry
+		// itself is skipped — its summary was already injected above.
+		for i := compactionIndex; i < len(branch); i++ {
+			entry := branch[i]
+			switch e := entry.(type) {
+			case *MessageEntry:
+				msg, err := e.ToMessage()
+				if err != nil {
+					continue
+				}
+				msgs := msg.ToLLMMessages()
+				messages = append(messages, msgs...)
+
+			case *BranchSummaryEntry:
+				if e.Summary != "" {
+					messages = append(messages, fantasy.Message{
+						Role: fantasy.MessageRoleUser,
+						Content: []fantasy.MessagePart{
+							fantasy.TextPart{
+								Text: fmt.Sprintf("[Branch context: %s]", e.Summary),
+							},
+						},
+					})
+				}
+
+			case *ModelChangeEntry:
+				provider = e.Provider
+				modelID = e.ModelID
+
+			case *CompactionEntry:
+				// Summary already injected above.
+				continue
+			}
+		}
+
 		return messages, provider, modelID
 	}
 
@@ -1030,44 +1034,22 @@ func (tm *TreeManager) GetContextEntryIDs() []string {
 
 	var ids []string
 
-	// If there's a compaction, we need to collect IDs from:
-	// 1. Entries after the compaction entry in the branch (newer messages)
-	// 2. Entries from FirstKeptEntryID onwards (kept messages)
+	// If there's a compaction, we collect IDs in the same order as
+	// BuildContext: [summary placeholder, kept messages, post-compaction
+	// messages]. This ordering must stay in sync with BuildContext so a
+	// cut-point index can be mapped back to the correct entry ID.
 	if lastCompaction != nil {
 		// Placeholder for the summary system message (no entry ID).
 		ids = append(ids, "")
 
-		// Collect IDs from entries after the compaction entry (newer messages).
-		for i := compactionIndex + 1; i < len(branch); i++ {
-			entry := branch[i]
-			switch e := entry.(type) {
-			case *MessageEntry:
-				msg, err := e.ToMessage()
-				if err != nil {
-					continue
-				}
-				msgs := msg.ToLLMMessages()
-				for range msgs {
-					ids = append(ids, e.ID)
-				}
-
-			case *BranchSummaryEntry:
-				if e.Summary != "" {
-					ids = append(ids, e.ID)
-				}
-			}
-		}
-
-		// Collect IDs from the kept messages starting at FirstKeptEntryID.
-		// We iterate through entries in order (not using getBranchLocked) to avoid
-		// walking back to old compacted messages.
-		// We stop when we reach the compaction entry to avoid double-counting.
+		// Step 1: IDs of the kept messages starting at FirstKeptEntryID.
+		// Iterate tm.entries in append order and stop at the compaction
+		// entry to avoid double-counting post-compaction messages.
 		if lastCompaction.FirstKeptEntryID != "" {
 			found := false
 			for _, entry := range tm.entries {
 				entryID := tm.EntryID(entry)
 
-				// Skip entries until we reach the first kept entry.
 				if !found {
 					if entryID == lastCompaction.FirstKeptEntryID {
 						found = true
@@ -1076,7 +1058,6 @@ func (tm *TreeManager) GetContextEntryIDs() []string {
 					}
 				}
 
-				// Stop when we reach the compaction entry itself.
 				if entryID == lastCompaction.ID {
 					break
 				}
@@ -1100,6 +1081,28 @@ func (tm *TreeManager) GetContextEntryIDs() []string {
 			}
 		}
 
+		// Step 2: IDs of entries after the compaction entry on the current
+		// branch (post-compaction messages).
+		for i := compactionIndex + 1; i < len(branch); i++ {
+			entry := branch[i]
+			switch e := entry.(type) {
+			case *MessageEntry:
+				msg, err := e.ToMessage()
+				if err != nil {
+					continue
+				}
+				msgs := msg.ToLLMMessages()
+				for range msgs {
+					ids = append(ids, e.ID)
+				}
+
+			case *BranchSummaryEntry:
+				if e.Summary != "" {
+					ids = append(ids, e.ID)
+				}
+			}
+		}
+
 		return ids
 	}
 
@@ -1350,15 +1353,44 @@ func (tm *TreeManager) buildTreeNodeDepth(id string, depth int, visited map[stri
 // --- Path conventions ---
 
 // DefaultSessionDir returns the default session storage directory for a cwd.
-// Convention: ~/.kit/sessions/--<cwd-path>--/
+// Convention: ~/.kit/sessions/<encoded-cwd>, where path separators are
+// encoded as "--" with no leading or trailing dashes — e.g.
+// /home/user/proj becomes home--user--proj. See encodeCwdForDir for the
+// full encoding rules (including Windows path handling).
 func DefaultSessionDir(cwd string) string {
 	home, err := os.UserHomeDir()
 	if err != nil {
 		home = "."
 	}
-	// Convert path separators to double dashes.
-	safeCwd := strings.ReplaceAll(cwd, string(filepath.Separator), "--")
+	return filepath.Join(home, ".kit", "sessions", encodeCwdForDir(cwd))
+}
+
+// encodeCwdForDir converts a working-directory path into a single, filesystem-
+// safe directory name. Path separators are replaced with double dashes and
+// characters that are illegal in Windows directory names — most importantly
+// the colon that follows the drive letter (e.g. `C:\foo` → `C--foo`) — are
+// stripped. The result is identical to the previous Unix-only encoding for
+// paths that do not contain such characters, so existing session directories
+// are preserved.
+func encodeCwdForDir(cwd string) string {
+	// Convert both `/` and `\` to double dashes so encoding is stable across
+	// platforms and remains correct on Windows where `filepath.Separator`
+	// would otherwise miss forward-slash style paths.
+	safeCwd := strings.ReplaceAll(cwd, "\\", "--")
+	safeCwd = strings.ReplaceAll(safeCwd, "/", "--")
 	// Remove leading separator replacement.
 	safeCwd = strings.TrimPrefix(safeCwd, "--")
-	return filepath.Join(home, ".kit", "sessions", safeCwd)
+	// Strip characters that are illegal in directory names on Windows
+	// (`< > : " | ? *`). On Unix these characters are legal but rare in
+	// practice; stripping them keeps the encoding portable.
+	replacer := strings.NewReplacer(
+		":", "",
+		"<", "",
+		">", "",
+		"\"", "",
+		"|", "",
+		"?", "",
+		"*", "",
+	)
+	return replacer.Replace(safeCwd)
 }

internal/tools/connection_pool.go

@@ -47,6 +47,7 @@ type MCPConnection struct {
 	client       client.MCPClient
 	serverName   string
 	serverConfig config.MCPServerConfig
+	initResult   *mcp.InitializeResult // captured at handshake; nil before initialize
 	lastUsed     time.Time
 	isHealthy    bool
 	errorCount   int
@@ -262,7 +263,9 @@ func (p *MCPConnectionPool) createConnection(ctx context.Context, serverName str
 		}
 	}
 
-	if err := p.initializeClient(ctx, mcpClient); err != nil {
+	conn := &MCPConnection{}
+
+	if err := p.initializeClient(ctx, mcpClient, conn); err != nil {
 		// Streamable HTTP transport returns OAuth error during Initialize()
 		if oauthEnabled && IsOAuthError(err) {
 			if flowErr := p.oauthFlow.RunAuthFlow(ctx, serverName, err); flowErr != nil {
@@ -270,7 +273,7 @@ func (p *MCPConnectionPool) createConnection(ctx context.Context, serverName str
 				return nil, fmt.Errorf("OAuth authorization failed: %w", flowErr)
 			}
 			// Retry initialization after successful auth
-			if err := p.initializeClient(ctx, mcpClient); err != nil {
+			if err := p.initializeClient(ctx, mcpClient, conn); err != nil {
 				_ = mcpClient.Close()
 				return nil, err
 			}
@@ -280,15 +283,11 @@ func (p *MCPConnectionPool) createConnection(ctx context.Context, serverName str
 		}
 	}
 
-	conn := &MCPConnection{
-		client:       mcpClient,
-		serverName:   serverName,
-		serverConfig: serverConfig,
-		lastUsed:     time.Now(),
-		isHealthy:    true,
-		errorCount:   0,
-		lastError:    nil,
-	}
+	conn.client = mcpClient
+	conn.serverName = serverName
+	conn.serverConfig = serverConfig
+	conn.lastUsed = time.Now()
+	conn.isHealthy = true
 
 	if p.debugLogger != nil && p.debugLogger.IsDebugEnabled() {
 		p.debugLogger.LogDebug(fmt.Sprintf("[POOL] Created connection for %s", serverName))
@@ -346,49 +345,70 @@ func (p *MCPConnectionPool) createStdioClient(ctx context.Context, serverConfig
 	return stdioClient, nil
 }
 
-// createSSEClient creates an SSE client
+// parseHeaders parses "Key: Value" header strings into a map.
+func parseHeaders(raw []string) map[string]string {
+	if len(raw) == 0 {
+		return nil
+	}
+	headers := make(map[string]string)
+	for _, header := range raw {
+		parts := strings.SplitN(header, ":", 2)
+		if len(parts) == 2 {
+			key := strings.TrimSpace(parts[0])
+			value := strings.TrimSpace(parts[1])
+			headers[key] = value
+		}
+	}
+	if len(headers) == 0 {
+		return nil
+	}
+	return headers
+}
+
+// buildOAuthConfig constructs a transport.OAuthConfig from the server config
+// and the pool's OAuth flow. Returns nil if OAuth is not applicable.
+func (p *MCPConnectionPool) buildOAuthConfig(serverConfig config.MCPServerConfig) (*transport.OAuthConfig, error) {
+	if p.oauthFlow == nil || serverConfig.NoOAuth {
+		return nil, nil
+	}
+	tokenStore, err := p.createTokenStore(serverConfig.URL)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create token store: %w", err)
+	}
+	cfg := &transport.OAuthConfig{
+		RedirectURI: p.oauthFlow.handler.RedirectURI(),
+		PKCEEnabled: true,
+		TokenStore:  tokenStore,
+	}
+	if serverConfig.OAuthClientID != "" {
+		cfg.ClientID = serverConfig.OAuthClientID
+	}
+	if serverConfig.OAuthClientSecret != "" {
+		cfg.ClientSecret = serverConfig.OAuthClientSecret
+	}
+	if len(serverConfig.OAuthScopes) > 0 {
+		cfg.Scopes = serverConfig.OAuthScopes
+	}
+	return cfg, nil
+}
+
 func (p *MCPConnectionPool) createSSEClient(ctx context.Context, serverConfig config.MCPServerConfig) (client.MCPClient, error) {
 	var options []transport.ClientOption
 
-	if len(serverConfig.Headers) > 0 {
-		headers := make(map[string]string)
-		for _, header := range serverConfig.Headers {
-			parts := strings.SplitN(header, ":", 2)
-			if len(parts) == 2 {
-				key := strings.TrimSpace(parts[0])
-				value := strings.TrimSpace(parts[1])
-				headers[key] = value
-			}
-		}
-		if len(headers) > 0 {
-			options = append(options, transport.WithHeaders(headers))
-		}
+	if headers := parseHeaders(serverConfig.Headers); headers != nil {
+		options = append(options, transport.WithHeaders(headers))
 	}
 
 	// Enable OAuth for remote transports when an auth handler is configured
 	// and the server hasn't opted out via NoOAuth. Public MCP servers (e.g.
 	// PubMed) set NoOAuth to skip dynamic client registration and token
 	// exchange, which would otherwise fail with a 404.
-	if p.oauthFlow != nil && !serverConfig.NoOAuth {
-		tokenStore, tsErr := p.createTokenStore(serverConfig.URL)
-		if tsErr != nil {
-			return nil, fmt.Errorf("failed to create token store: %w", tsErr)
-		}
-		oauthCfg := transport.OAuthConfig{
-			RedirectURI: p.oauthFlow.handler.RedirectURI(),
-			PKCEEnabled: true,
-			TokenStore:  tokenStore,
-		}
-		if serverConfig.OAuthClientID != "" {
-			oauthCfg.ClientID = serverConfig.OAuthClientID
-		}
-		if serverConfig.OAuthClientSecret != "" {
-			oauthCfg.ClientSecret = serverConfig.OAuthClientSecret
-		}
-		if len(serverConfig.OAuthScopes) > 0 {
-			oauthCfg.Scopes = serverConfig.OAuthScopes
-		}
-		options = append(options, transport.WithOAuth(oauthCfg))
+	oauthCfg, err := p.buildOAuthConfig(serverConfig)
+	if err != nil {
+		return nil, err
+	}
+	if oauthCfg != nil {
+		options = append(options, transport.WithOAuth(*oauthCfg))
 	}
 
 	sseClient, err := client.NewSSEMCPClient(serverConfig.URL, options...)
@@ -407,43 +427,18 @@ func (p *MCPConnectionPool) createSSEClient(ctx context.Context, serverConfig co
 func (p *MCPConnectionPool) createStreamableClient(ctx context.Context, serverConfig config.MCPServerConfig) (client.MCPClient, error) {
 	var options []transport.StreamableHTTPCOption
 
-	if len(serverConfig.Headers) > 0 {
-		headers := make(map[string]string)
-		for _, header := range serverConfig.Headers {
-			parts := strings.SplitN(header, ":", 2)
-			if len(parts) == 2 {
-				key := strings.TrimSpace(parts[0])
-				value := strings.TrimSpace(parts[1])
-				headers[key] = value
-			}
-		}
-		if len(headers) > 0 {
-			options = append(options, transport.WithHTTPHeaders(headers))
-		}
+	if headers := parseHeaders(serverConfig.Headers); headers != nil {
+		options = append(options, transport.WithHTTPHeaders(headers))
 	}
 
 	// Enable OAuth for remote transports when an auth handler is configured
 	// and the server hasn't opted out via NoOAuth.
-	if p.oauthFlow != nil && !serverConfig.NoOAuth {
-		tokenStore, tsErr := p.createTokenStore(serverConfig.URL)
-		if tsErr != nil {
-			return nil, fmt.Errorf("failed to create token store: %w", tsErr)
-		}
-		oauthCfg := transport.OAuthConfig{
-			RedirectURI: p.oauthFlow.handler.RedirectURI(),
-			PKCEEnabled: true,
-			TokenStore:  tokenStore,
-		}
-		if serverConfig.OAuthClientID != "" {
-			oauthCfg.ClientID = serverConfig.OAuthClientID
-		}
-		if serverConfig.OAuthClientSecret != "" {
-			oauthCfg.ClientSecret = serverConfig.OAuthClientSecret
-		}
-		if len(serverConfig.OAuthScopes) > 0 {
-			oauthCfg.Scopes = serverConfig.OAuthScopes
-		}
-		options = append(options, transport.WithHTTPOAuth(oauthCfg))
+	oauthCfg, err := p.buildOAuthConfig(serverConfig)
+	if err != nil {
+		return nil, err
+	}
+	if oauthCfg != nil {
+		options = append(options, transport.WithHTTPOAuth(*oauthCfg))
 	}
 
 	streamableClient, err := client.NewStreamableHttpClient(serverConfig.URL, options...)
@@ -484,8 +479,10 @@ func (p *MCPConnectionPool) createTokenStore(serverURL string) (transport.TokenS
 	return NewFileTokenStore(serverURL)
 }
 
-// initializeClient initializes the client
-func (p *MCPConnectionPool) initializeClient(ctx context.Context, client client.MCPClient) error {
+// initializeClient initializes the client and captures the server's
+// initialize result on the supplied connection so callers can later
+// inspect advertised capabilities (e.g. task support).
+func (p *MCPConnectionPool) initializeClient(ctx context.Context, c client.MCPClient, conn *MCPConnection) error {
 	initCtx, cancel := context.WithTimeout(ctx, 5*time.Minute)
 	defer cancel()
 
@@ -495,12 +492,21 @@ func (p *MCPConnectionPool) initializeClient(ctx context.Context, client client.
 		Name:    "kit",
 		Version: "1.0.0",
 	}
-	initRequest.Params.Capabilities = mcp.ClientCapabilities{}
+	// Advertise task support so servers may return CreateTaskResult for
+	// long-running tools/call requests instead of blocking the connection
+	// until completion. The client is responsible for polling tasks/get and
+	// tasks/result until the task reaches a terminal state.
+	initRequest.Params.Capabilities = mcp.ClientCapabilities{
+		Tasks: mcp.NewTasksCapability(),
+	}
 
-	_, err := client.Initialize(initCtx, initRequest)
+	initResult, err := c.Initialize(initCtx, initRequest)
 	if err != nil {
 		return fmt.Errorf("initialization timeout or failed: %w", err)
 	}
+	if conn != nil {
+		conn.initResult = initResult
+	}
 
 	if p.debugLogger != nil && p.debugLogger.IsDebugEnabled() {
 		p.debugLogger.LogDebug("[POOL] Initialized MCP client")
@@ -615,6 +621,54 @@ func (c *MCPConnection) ServerName() string {
 	return c.serverName
 }
 
+// InitializeResult returns the result captured from the server's initialize
+// response, or nil if the connection was created before initialize completed.
+// Callers can inspect ServerCapabilities.Tasks to discover task-related
+// capability advertisements.
+func (c *MCPConnection) InitializeResult() *mcp.InitializeResult {
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+	return c.initResult
+}
+
+// SupportsToolTasks reports whether the server advertised support for
+// task-augmented tools/call requests. Returns false when the connection has
+// not yet completed initialization or when the server omitted task
+// capabilities.
+func (c *MCPConnection) SupportsToolTasks() bool {
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+	return supportsToolTasksFromInit(c.initResult)
+}
+
+// supportsToolTasksFromInit reports whether the supplied InitializeResult
+// advertises task-augmented tools/call support. Extracted to a free function
+// for unit testing without standing up a connection.
+func supportsToolTasksFromInit(init *mcp.InitializeResult) bool {
+	if init == nil || init.Capabilities.Tasks == nil {
+		return false
+	}
+	req := init.Capabilities.Tasks.Requests
+	if req == nil || req.Tools == nil {
+		return false
+	}
+	return req.Tools.Call != nil
+}
+
+// ServerSupportsToolTasks reports whether the named server's connection
+// advertises task-augmented tools/call support. Returns false when no
+// connection exists for the server or when the server didn't advertise the
+// capability.
+func (p *MCPConnectionPool) ServerSupportsToolTasks(serverName string) bool {
+	p.mu.RLock()
+	conn, ok := p.connections[serverName]
+	p.mu.RUnlock()
+	if !ok {
+		return false
+	}
+	return conn.SupportsToolTasks()
+}
+
 // GetClients returns a map of all MCP clients currently in the pool.
 // The map keys are server names and values are the corresponding MCP client instances.
 // The returned map is a copy and modifications won't affect the pool.

internal/tools/mcp.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"encoding/base64"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"maps"
 	"slices"
@@ -13,6 +14,7 @@ import (
 	log "github.com/charmbracelet/log"
 
 	"github.com/mark3labs/kit/internal/config"
+	"github.com/mark3labs/mcp-go/client"
 	"github.com/mark3labs/mcp-go/mcp"
 )
 
@@ -141,6 +143,11 @@ type MCPToolManager struct {
 	debug             bool
 	debugLogger       DebugLogger
 
+	// taskCfg controls task-augmented tools/call execution. The zero value
+	// means: auto-detect server capability, no progress callback, default
+	// poll/timeout.
+	taskCfg MCPTaskConfig
+
 	// onServerLoaded, if non-nil, is called when each server finishes loading.
 	// Called with server name, tool count, and error (nil on success).
 	onServerLoaded func(serverName string, toolCount int, err error)
@@ -220,6 +227,21 @@ func (m *MCPToolManager) SetOnToolsChanged(cb func()) {
 	m.onToolsChanged = cb
 }
 
+// SetTaskConfig sets the task-augmented tools/call configuration. Call
+// this before LoadTools / AddServer if you want the per-server mode
+// override and progress handler to take effect for the very first call.
+// Subsequent calls replace the previous configuration wholesale.
+func (m *MCPToolManager) SetTaskConfig(cfg MCPTaskConfig) {
+	m.taskCfg = cfg
+}
+
+// TaskConfig returns the manager's current task-augmented tools/call
+// configuration. The zero value means: defer to per-server config and
+// auto-detected capability, with no progress callback and default polling.
+func (m *MCPToolManager) TaskConfig() MCPTaskConfig {
+	return m.taskCfg
+}
+
 // AddServer connects to a new MCP server at runtime and loads its tools.
 // The server's tools are immediately available to the agent after this call.
 // Returns the number of tools loaded from the server.
@@ -551,6 +573,14 @@ func (m *MCPToolManager) loadServerTools(ctx context.Context, serverName string,
 // checks, OAuth re-authorization, and connection error tracking.
 // The inputJSON parameter is the raw JSON arguments from the LLM.
 // Returns the result content, error flag, and any execution error.
+//
+// When the per-server TasksMode resolves to "always", or to "auto" and the
+// server advertised tasks/toolCalls capability during initialize, the call
+// is augmented with TaskParams. If the server elects to respond with a
+// CreateTaskResult the manager polls tasks/get / tasks/result until the
+// task reaches a terminal state, transparently presenting the final
+// CallToolResult-equivalent content to the agent layer. Context
+// cancellation triggers a best-effort tasks/cancel.
 func (m *MCPToolManager) ExecuteTool(ctx context.Context, prefixedName, inputJSON string) (*MCPToolResult, error) {
 	m.mu.Lock()
 	mapping, ok := m.toolMap[prefixedName]
@@ -582,49 +612,221 @@ func (m *MCPToolManager) ExecuteTool(ctx context.Context, prefixedName, inputJSO
 		return nil, fmt.Errorf("failed to get healthy connection from pool: %w", err)
 	}
 
-	callRequest := mcp.CallToolRequest{
-		Request: mcp.Request{
-			Method: "tools/call",
-		},
-		Params: mcp.CallToolParams{
-			Name:      mapping.originalName,
-			Arguments: arguments,
-		},
+	callParams := mcp.CallToolParams{
+		Name:      mapping.originalName,
+		Arguments: arguments,
 	}
 
-	// Call the MCP tool using the original (unprefixed) name
-	result, err := conn.client.CallTool(ctx, callRequest)
-	if err != nil {
-		// Handle OAuth re-authorization: token may have expired mid-session.
-		if m.connectionPool.oauthFlow != nil && IsOAuthError(err) {
-			if flowErr := m.connectionPool.oauthFlow.RunAuthFlow(ctx, mapping.serverName, err); flowErr != nil {
+	// Decide whether to augment the request with TaskParams. Modes:
+	//   never  — never augment (synchronous-only).
+	//   always — always augment, even without server capability.
+	//   auto   — augment only when the server advertised tasks/toolCalls.
+	mode := m.resolveTaskMode(mapping.serverName, mapping.serverConfig)
+	useTask := mode == MCPTaskModeAlways ||
+		(mode == MCPTaskModeAuto && conn.SupportsToolTasks())
+	if useTask {
+		var ttl *int64
+		if m.taskCfg.DefaultTTL > 0 {
+			ms := m.taskCfg.DefaultTTL.Milliseconds()
+			ttl = &ms
+		}
+		callParams.Task = &mcp.TaskParams{TTL: ttl}
+	}
+
+	// Synchronous fast path: no task augmentation. Use the upstream client
+	// helper which keeps content-block typing identical to historical
+	// behaviour.
+	if !useTask {
+		callRequest := mcp.CallToolRequest{
+			Request: mcp.Request{Method: "tools/call"},
+			Params:  callParams,
+		}
+		result, callErr := conn.client.CallTool(ctx, callRequest)
+		if callErr != nil {
+			if m.connectionPool.oauthFlow != nil && IsOAuthError(callErr) {
+				if flowErr := m.connectionPool.oauthFlow.RunAuthFlow(ctx, mapping.serverName, callErr); flowErr != nil {
+					return nil, fmt.Errorf("OAuth re-authorization failed for tool %s: %w", mapping.originalName, flowErr)
+				}
+				result, callErr = conn.client.CallTool(ctx, callRequest)
+				if callErr != nil {
+					m.connectionPool.HandleConnectionError(mapping.serverName, callErr)
+					return nil, fmt.Errorf("failed to call mcp tool after re-auth: %w", callErr)
+				}
+			} else {
+				m.connectionPool.HandleConnectionError(mapping.serverName, callErr)
+				return nil, fmt.Errorf("failed to call mcp tool: %w", callErr)
+			}
+		}
+		marshaledResult, mErr := json.Marshal(result)
+		if mErr != nil {
+			return nil, fmt.Errorf("failed to marshal mcp tool result: %w", mErr)
+		}
+		return &MCPToolResult{
+			Content: string(marshaledResult),
+			IsError: result.IsError,
+		}, nil
+	}
+
+	// Task-augmented path. Bypass the upstream CallTool helper because its
+	// ParseCallToolResult requires a "content" field that is absent from a
+	// CreateTaskResult.
+	rawClient, ok := conn.client.(*client.Client)
+	if !ok {
+		// Older client implementations — fall back to the synchronous shape.
+		callParams.Task = nil
+		callRequest := mcp.CallToolRequest{
+			Request: mcp.Request{Method: "tools/call"},
+			Params:  callParams,
+		}
+		result, callErr := conn.client.CallTool(ctx, callRequest)
+		if callErr != nil {
+			m.connectionPool.HandleConnectionError(mapping.serverName, callErr)
+			return nil, fmt.Errorf("failed to call mcp tool: %w", callErr)
+		}
+		marshaledResult, mErr := json.Marshal(result)
+		if mErr != nil {
+			return nil, fmt.Errorf("failed to marshal mcp tool result: %w", mErr)
+		}
+		return &MCPToolResult{Content: string(marshaledResult), IsError: result.IsError}, nil
+	}
+
+	callResult, taskResult, callErr := callToolWithTask(ctx, rawClient, callParams)
+	if callErr != nil {
+		if m.connectionPool.oauthFlow != nil && IsOAuthError(callErr) {
+			if flowErr := m.connectionPool.oauthFlow.RunAuthFlow(ctx, mapping.serverName, callErr); flowErr != nil {
 				return nil, fmt.Errorf("OAuth re-authorization failed for tool %s: %w", mapping.originalName, flowErr)
 			}
-			// Retry the tool call after successful re-auth.
-			result, err = conn.client.CallTool(ctx, callRequest)
-			if err != nil {
-				m.connectionPool.HandleConnectionError(mapping.serverName, err)
-				return nil, fmt.Errorf("failed to call mcp tool after re-auth: %w", err)
+			callResult, taskResult, callErr = callToolWithTask(ctx, rawClient, callParams)
+			if callErr != nil {
+				m.connectionPool.HandleConnectionError(mapping.serverName, callErr)
+				return nil, fmt.Errorf("failed to call mcp tool after re-auth: %w", callErr)
 			}
 		} else {
-			// Mark connection as unhealthy for automatic recovery
-			m.connectionPool.HandleConnectionError(mapping.serverName, err)
-			return nil, fmt.Errorf("failed to call mcp tool: %w", err)
+			m.connectionPool.HandleConnectionError(mapping.serverName, callErr)
+			return nil, fmt.Errorf("failed to call mcp tool: %w", callErr)
 		}
 	}
 
-	// Marshal the MCP result to JSON string
-	marshaledResult, err := json.Marshal(result)
-	if err != nil {
-		return nil, fmt.Errorf("failed to marshal mcp tool result: %w", err)
+	// Server chose to answer synchronously — same shape as the no-task path.
+	if callResult != nil {
+		marshaledResult, mErr := json.Marshal(callResult)
+		if mErr != nil {
+			return nil, fmt.Errorf("failed to marshal mcp tool result: %w", mErr)
+		}
+		return &MCPToolResult{
+			Content: string(marshaledResult),
+			IsError: callResult.IsError,
+		}, nil
 	}
 
+	// Asynchronous task path: poll until terminal, then return the result.
+	if taskResult == nil {
+		return nil, errors.New("mcp tools/call returned neither result nor task")
+	}
+	final, pollErr := pollTaskUntilTerminal(
+		ctx, rawClient, mapping.serverName, taskResult.Task,
+		m.taskCfg, m.taskCfg.Progress,
+	)
+	if pollErr != nil {
+		return nil, fmt.Errorf("task execution failed: %w", pollErr)
+	}
+
+	// Adapt TaskResultResult → CallToolResult for downstream JSON shape parity.
+	adapted := &mcp.CallToolResult{
+		Content:           final.Content,
+		StructuredContent: final.StructuredContent,
+		IsError:           final.IsError,
+	}
+	marshaledResult, mErr := json.Marshal(adapted)
+	if mErr != nil {
+		return nil, fmt.Errorf("failed to marshal mcp tool result: %w", mErr)
+	}
 	return &MCPToolResult{
 		Content: string(marshaledResult),
-		IsError: result.IsError,
+		IsError: final.IsError,
 	}, nil
 }
 
+// resolveTaskMode resolves the effective task mode for a given server.
+// Programmatic overrides via SetTaskConfig take precedence over the
+// per-server TasksMode in MCPServerConfig. Empty / unknown values map to
+// MCPTaskModeAuto.
+func (m *MCPToolManager) resolveTaskMode(name string, cfg config.MCPServerConfig) MCPTaskMode {
+	if m.taskCfg.PerServerMode != nil {
+		if v, ok := m.taskCfg.PerServerMode[name]; ok {
+			return v
+		}
+	}
+	return ParseTaskMode(cfg.TasksMode)
+}
+
+// ListServerTasks queries tasks/list on the named server and returns the
+// active and recent tasks the server is willing to disclose. Errors are
+// returned untouched (callers commonly ignore METHOD_NOT_FOUND when the
+// server didn't advertise tasks/list capability).
+func (m *MCPToolManager) ListServerTasks(ctx context.Context, serverName string) ([]MCPTaskInfo, error) {
+	c, err := m.taskClient(serverName)
+	if err != nil {
+		return nil, err
+	}
+	res, err := c.ListTasks(ctx, mcp.ListTasksRequest{})
+	if err != nil {
+		return nil, fmt.Errorf("tasks/list on %s: %w", serverName, err)
+	}
+	out := make([]MCPTaskInfo, 0, len(res.Tasks))
+	for _, t := range res.Tasks {
+		out = append(out, taskFromMCP(serverName, t))
+	}
+	return out, nil
+}
+
+// GetServerTask queries tasks/get for a single task on the named server.
+func (m *MCPToolManager) GetServerTask(ctx context.Context, serverName, taskID string) (MCPTaskInfo, error) {
+	c, err := m.taskClient(serverName)
+	if err != nil {
+		return MCPTaskInfo{}, err
+	}
+	res, err := c.GetTask(ctx, mcp.GetTaskRequest{Params: mcp.GetTaskParams{TaskId: taskID}})
+	if err != nil {
+		return MCPTaskInfo{}, fmt.Errorf("tasks/get on %s: %w", serverName, err)
+	}
+	return taskFromMCP(serverName, res.Task), nil
+}
+
+// CancelServerTask issues tasks/cancel for a task on the named server.
+// Returns the post-cancel task state when the server responded with one.
+func (m *MCPToolManager) CancelServerTask(ctx context.Context, serverName, taskID string) (MCPTaskInfo, error) {
+	c, err := m.taskClient(serverName)
+	if err != nil {
+		return MCPTaskInfo{}, err
+	}
+	res, err := c.CancelTask(ctx, mcp.CancelTaskRequest{Params: mcp.CancelTaskParams{TaskId: taskID}})
+	if err != nil {
+		return MCPTaskInfo{}, fmt.Errorf("tasks/cancel on %s: %w", serverName, err)
+	}
+	return taskFromMCP(serverName, res.Task), nil
+}
+
+// taskClient returns the *client.Client for a server. Tasks endpoints are
+// not part of the upstream MCPClient interface so callers must work with
+// the concrete client. Returns an error when the connection is missing
+// or backed by a non-standard client type.
+func (m *MCPToolManager) taskClient(serverName string) (*client.Client, error) {
+	if m.connectionPool == nil {
+		return nil, fmt.Errorf("no connection pool available")
+	}
+	clients := m.connectionPool.GetClients()
+	raw, ok := clients[serverName]
+	if !ok {
+		return nil, fmt.Errorf("MCP server %q not loaded", serverName)
+	}
+	c, ok := raw.(*client.Client)
+	if !ok {
+		return nil, fmt.Errorf("MCP server %q does not support task RPCs", serverName)
+	}
+	return c, nil
+}
+
 // GetTools returns all loaded MCP tools from all configured MCP servers.
 // Tools are returned with their prefixed names (serverName__toolName) to ensure uniqueness.
 func (m *MCPToolManager) GetTools() []MCPTool {

internal/tools/mcp_tasks.go

@@ -0,0 +1,404 @@
+package tools
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"strings"
+	"sync/atomic"
+	"time"
+
+	"github.com/mark3labs/mcp-go/client"
+	"github.com/mark3labs/mcp-go/client/transport"
+	"github.com/mark3labs/mcp-go/mcp"
+)
+
+// MCPTaskMode controls when the connection pool augments tools/call requests
+// with MCP task metadata. See https://modelcontextprotocol.io/specification/2025-11-25/basic/utilities/tasks.
+type MCPTaskMode string
+
+const (
+	// MCPTaskModeAuto augments tools/call with task metadata only when the
+	// server advertises tasks/toolCalls capability during initialize.
+	MCPTaskModeAuto MCPTaskMode = "auto"
+	// MCPTaskModeNever forces every tools/call to be issued synchronously
+	// (no Task field in the request), regardless of server capability.
+	MCPTaskModeNever MCPTaskMode = "never"
+	// MCPTaskModeAlways always sets a Task field on the tools/call request,
+	// even when the server didn't advertise task support. The server may
+	// still respond synchronously; this just opts in unconditionally on
+	// the client side.
+	MCPTaskModeAlways MCPTaskMode = "always"
+)
+
+// ParseTaskMode normalises a per-server tasks-mode string from
+// configuration. Empty input maps to MCPTaskModeAuto. Unknown values are
+// also treated as MCPTaskModeAuto so a stray config typo never breaks
+// existing flows.
+func ParseTaskMode(s string) MCPTaskMode {
+	switch strings.ToLower(strings.TrimSpace(s)) {
+	case "", "auto":
+		return MCPTaskModeAuto
+	case "never", "off", "disabled":
+		return MCPTaskModeNever
+	case "always", "force":
+		return MCPTaskModeAlways
+	default:
+		return MCPTaskModeAuto
+	}
+}
+
+// MCPTaskInfo is the connection-layer view of an MCP Task. It mirrors the
+// upstream mcp.Task but exposes Go-native types and includes the originating
+// server name. SDK-level wrappers re-export this under public-facing names.
+type MCPTaskInfo struct {
+	// Server is the configured MCP server name this task lives on.
+	Server string
+	// TaskID is the server-assigned identifier for the task.
+	TaskID string
+	// Status is the current task lifecycle state.
+	Status mcp.TaskStatus
+	// StatusMessage is an optional human-readable description.
+	StatusMessage string
+	// CreatedAt is the wall-clock time the task was created (best-effort
+	// parsed from the server's ISO-8601 timestamp; zero on parse failure).
+	CreatedAt time.Time
+	// UpdatedAt is the wall-clock time the task was last updated (best-
+	// effort parsed; zero on parse failure).
+	UpdatedAt time.Time
+	// TTL is the time-to-live the server intends to retain the task after
+	// creation. Zero means the server did not advertise a TTL.
+	TTL time.Duration
+	// PollInterval is the suggested polling interval. Zero means use the
+	// client's default.
+	PollInterval time.Duration
+}
+
+// MCPTaskProgress is emitted while the connection pool is waiting on a
+// task-augmented tool call. It provides minimal feedback for SDK consumers
+// that want to render progress widgets without subscribing to the full
+// notifications/tasks/status channel (Phase 2).
+type MCPTaskProgress struct {
+	Server  string
+	TaskID  string
+	Status  mcp.TaskStatus
+	Message string
+}
+
+// MCPTaskProgressHandler is invoked once after a task is accepted and on
+// every status transition observed by the polling loop. The final
+// invocation always carries a terminal status. Implementations must not
+// block; long work should be queued on a goroutine.
+type MCPTaskProgressHandler func(MCPTaskProgress)
+
+// MCPTaskConfig configures task-aware tool execution on the manager.
+// All fields are optional; the zero value disables progress callbacks and
+// applies sensible defaults.
+type MCPTaskConfig struct {
+	// PerServerMode overrides the per-server TasksMode resolved from
+	// MCPServerConfig. Keys are server names. Missing entries fall back
+	// to the value from config. Used by SDK consumers that want to set
+	// modes programmatically.
+	PerServerMode map[string]MCPTaskMode
+
+	// DefaultTTL is the TTL hint sent in TaskParams when augmenting a
+	// tools/call. Zero means omit the TTL — let the server pick its own.
+	DefaultTTL time.Duration
+
+	// PollInterval is the fallback interval between tasks/get requests
+	// when the server does not suggest one. Zero defaults to 1 second.
+	PollInterval time.Duration
+
+	// MaxPollInterval caps the polling interval. Zero defaults to 5 seconds.
+	MaxPollInterval time.Duration
+
+	// Timeout is the maximum wall-clock duration to wait for a task to
+	// reach a terminal state. Zero defaults to 15 minutes. Independent
+	// of the per-call context deadline; whichever fires first wins.
+	Timeout time.Duration
+
+	// Progress, if non-nil, receives every status transition observed by
+	// the polling loop.
+	Progress MCPTaskProgressHandler
+}
+
+func (c MCPTaskConfig) resolved() MCPTaskConfig {
+	if c.PollInterval <= 0 {
+		c.PollInterval = 1 * time.Second
+	}
+	if c.MaxPollInterval <= 0 {
+		c.MaxPollInterval = 5 * time.Second
+	}
+	if c.Timeout <= 0 {
+		c.Timeout = 15 * time.Minute
+	}
+	return c
+}
+
+// requestIDCounter generates monotonically increasing JSON-RPC request IDs
+// for low-level tools/call invocations that bypass the upstream client's
+// ParseCallToolResult helper (necessary because that helper rejects task
+// responses for lacking a "content" field).
+//
+// The counter is process-wide rather than per-manager so multiple managers
+// or repeated calls within the same connection produce unique IDs.
+var requestIDCounter atomic.Int64
+
+func nextRequestID() mcp.RequestId {
+	return mcp.NewRequestId(requestIDCounter.Add(1))
+}
+
+// callToolWithTask issues tools/call directly on the transport so we can
+// observe both response shapes:
+//
+//   - {"content": [...], ...}  — synchronous CallToolResult.
+//   - {"task": {...}, ...}     — asynchronous CreateTaskResult.
+//
+// On success exactly one of (callResult, taskResult) is non-nil. The
+// upstream client.CallTool helper parses the response with
+// mcp.ParseCallToolResult which requires a "content" field, so it cannot
+// be used for task-augmented calls.
+func callToolWithTask(
+	ctx context.Context,
+	c *client.Client,
+	params mcp.CallToolParams,
+) (callResult *mcp.CallToolResult, taskResult *mcp.CreateTaskResult, err error) {
+	tr := c.GetTransport()
+	if tr == nil {
+		return nil, nil, errors.New("mcp client has no transport")
+	}
+
+	req := transport.JSONRPCRequest{
+		JSONRPC: mcp.JSONRPC_VERSION,
+		ID:      nextRequestID(),
+		Method:  string(mcp.MethodToolsCall),
+		Params:  params,
+	}
+
+	resp, sendErr := tr.SendRequest(ctx, req)
+	if sendErr != nil {
+		return nil, nil, sendErr
+	}
+	if resp.Error != nil {
+		return nil, nil, resp.Error.AsError()
+	}
+
+	// Peek at the raw result to decide which shape we got.
+	var probe struct {
+		Task    json.RawMessage `json:"task"`
+		Content json.RawMessage `json:"content"`
+	}
+	raw := resp.Result
+	if len(raw) == 0 {
+		return nil, nil, errors.New("empty tools/call result")
+	}
+	if uErr := json.Unmarshal(raw, &probe); uErr != nil {
+		return nil, nil, fmt.Errorf("decode tools/call result: %w", uErr)
+	}
+
+	if len(probe.Task) > 0 && string(probe.Task) != "null" {
+		// Task-augmented response.
+		var ct mcp.CreateTaskResult
+		if uErr := json.Unmarshal(raw, &ct); uErr != nil {
+			return nil, nil, fmt.Errorf("decode CreateTaskResult: %w", uErr)
+		}
+		return nil, &ct, nil
+	}
+
+	// Synchronous response — defer to the upstream parser so content blocks
+	// are typed correctly (TextContent, ImageContent, ResourceLink, etc.).
+	cr, pErr := mcp.ParseCallToolResult(&raw)
+	if pErr != nil {
+		return nil, nil, fmt.Errorf("parse CallToolResult: %w", pErr)
+	}
+	return cr, nil, nil
+}
+
+// pollTaskUntilTerminal blocks until the task reaches a terminal status,
+// the context is cancelled, or the configured timeout elapses. On
+// cancellation it best-effort issues tasks/cancel before returning.
+func pollTaskUntilTerminal(
+	ctx context.Context,
+	c *client.Client,
+	serverName string,
+	task mcp.Task,
+	cfg MCPTaskConfig,
+	progress MCPTaskProgressHandler,
+) (*mcp.TaskResultResult, error) {
+	cfg = cfg.resolved()
+	deadline := time.Now().Add(cfg.Timeout)
+
+	emit := func(status mcp.TaskStatus, msg string) {
+		if progress != nil {
+			progress(MCPTaskProgress{Server: serverName, TaskID: task.TaskId, Status: status, Message: msg})
+		}
+	}
+
+	emit(task.Status, task.StatusMessage)
+
+	current := task
+	interval := cfg.PollInterval
+	if current.PollInterval != nil && *current.PollInterval > 0 {
+		interval = time.Duration(*current.PollInterval) * time.Millisecond
+	}
+	if interval > cfg.MaxPollInterval {
+		interval = cfg.MaxPollInterval
+	}
+
+	for !current.Status.IsTerminal() {
+		if time.Now().After(deadline) {
+			cancelTaskBestEffort(c, current.TaskId)
+			return nil, fmt.Errorf("task %s timed out after %s", current.TaskId, cfg.Timeout)
+		}
+
+		// Wait between polls or abort early on context cancellation.
+		select {
+		case <-ctx.Done():
+			cancelTaskBestEffort(c, current.TaskId)
+			return nil, ctx.Err()
+		case <-time.After(interval):
+		}
+
+		got, err := c.GetTask(ctx, mcp.GetTaskRequest{
+			Params: mcp.GetTaskParams{TaskId: current.TaskId},
+		})
+		if err != nil {
+			// Transient transport hiccup — propagate immediately. The
+			// upstream agent layer treats this like any other tool error.
+			return nil, fmt.Errorf("tasks/get failed: %w", err)
+		}
+		current = got.Task
+		if current.Status != task.Status || current.StatusMessage != task.StatusMessage {
+			emit(current.Status, current.StatusMessage)
+			task = current
+		}
+
+		// Honour any updated suggested poll interval, capped at the limit.
+		if current.PollInterval != nil && *current.PollInterval > 0 {
+			interval = min(time.Duration(*current.PollInterval)*time.Millisecond, cfg.MaxPollInterval)
+		}
+	}
+
+	// Terminal state reached. Emit one last progress event and fetch the
+	// definitive tool result.
+	emit(current.Status, current.StatusMessage)
+
+	if current.Status == mcp.TaskStatusCancelled {
+		return nil, fmt.Errorf("task %s was cancelled", current.TaskId)
+	}
+
+	res, err := fetchTaskResult(ctx, c, current.TaskId)
+	if err != nil {
+		return nil, fmt.Errorf("tasks/result failed: %w", err)
+	}
+	if current.Status == mcp.TaskStatusFailed && res != nil && !res.IsError {
+		// The server flagged the task as failed but didn't decorate the
+		// result. Surface the status message so the caller still sees a
+		// useful tool-error.
+		return nil, fmt.Errorf("task %s failed: %s", current.TaskId, current.StatusMessage)
+	}
+	return res, nil
+}
+
+// fetchTaskResult issues tasks/result on the transport and parses the raw
+// response. The upstream client.TaskResult helper delegates to
+// mcp.ParseTaskResultResult which (as of mcp-go v0.51.0) looks for the
+// content array under a nested "result" key that never exists in the
+// wire format — leading to systematically empty Content. Doing the
+// parse here keeps the polling path working until that is fixed upstream.
+func fetchTaskResult(ctx context.Context, c *client.Client, taskID string) (*mcp.TaskResultResult, error) {
+	tr := c.GetTransport()
+	if tr == nil {
+		return nil, errors.New("mcp client has no transport")
+	}
+	req := transport.JSONRPCRequest{
+		JSONRPC: mcp.JSONRPC_VERSION,
+		ID:      nextRequestID(),
+		Method:  string(mcp.MethodTasksResult),
+		Params:  mcp.TaskResultParams{TaskId: taskID},
+	}
+	resp, err := tr.SendRequest(ctx, req)
+	if err != nil {
+		return nil, err
+	}
+	if resp.Error != nil {
+		return nil, resp.Error.AsError()
+	}
+
+	// Manually decode the wire shape: {"_meta": {...}, "content": [...],
+	// "structuredContent": ..., "isError": bool}.
+	var shape struct {
+		Meta              json.RawMessage   `json:"_meta"`
+		Content           []json.RawMessage `json:"content"`
+		StructuredContent any               `json:"structuredContent"`
+		IsError           bool              `json:"isError"`
+	}
+	if err := json.Unmarshal(resp.Result, &shape); err != nil {
+		return nil, fmt.Errorf("decode tasks/result: %w", err)
+	}
+
+	out := &mcp.TaskResultResult{
+		StructuredContent: shape.StructuredContent,
+		IsError:           shape.IsError,
+	}
+	if len(shape.Meta) > 0 && string(shape.Meta) != "null" {
+		var metaMap map[string]any
+		if err := json.Unmarshal(shape.Meta, &metaMap); err == nil {
+			out.Meta = mcp.NewMetaFromMap(metaMap)
+		}
+	}
+	for _, raw := range shape.Content {
+		var contentMap map[string]any
+		if err := json.Unmarshal(raw, &contentMap); err != nil {
+			return nil, fmt.Errorf("decode content block: %w", err)
+		}
+		parsed, err := mcp.ParseContent(contentMap)
+		if err != nil {
+			return nil, fmt.Errorf("parse content block: %w", err)
+		}
+		out.Content = append(out.Content, parsed)
+	}
+	return out, nil
+}
+
+// cancelTaskBestEffort issues tasks/cancel and ignores any error. Used on
+// context cancellation paths where the connection is already going away.
+func cancelTaskBestEffort(c *client.Client, taskID string) {
+	if c == nil || taskID == "" {
+		return
+	}
+	cancelCtx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+	_, _ = c.CancelTask(cancelCtx, mcp.CancelTaskRequest{
+		Params: mcp.CancelTaskParams{TaskId: taskID},
+	})
+}
+
+// taskFromMCP converts a wire-format mcp.Task to our richer connection-
+// layer view. Unparseable timestamps surface as the zero time.
+func taskFromMCP(serverName string, t mcp.Task) MCPTaskInfo {
+	out := MCPTaskInfo{
+		Server:        serverName,
+		TaskID:        t.TaskId,
+		Status:        t.Status,
+		StatusMessage: t.StatusMessage,
+	}
+	if t.CreatedAt != "" {
+		if v, err := time.Parse(time.RFC3339, t.CreatedAt); err == nil {
+			out.CreatedAt = v
+		}
+	}
+	if t.LastUpdatedAt != "" {
+		if v, err := time.Parse(time.RFC3339, t.LastUpdatedAt); err == nil {
+			out.UpdatedAt = v
+		}
+	}
+	if t.TTL != nil {
+		out.TTL = time.Duration(*t.TTL) * time.Millisecond
+	}
+	if t.PollInterval != nil {
+		out.PollInterval = time.Duration(*t.PollInterval) * time.Millisecond
+	}
+	return out
+}

internal/tools/mcp_tasks_test.go

@@ -0,0 +1,294 @@
+package tools
+
+import (
+	"context"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/mark3labs/kit/internal/config"
+	"github.com/mark3labs/mcp-go/mcp"
+	"github.com/mark3labs/mcp-go/server"
+)
+
+// newTaskTestInProcessServer builds an in-process MCP server with a
+// task-augmented tool. The handler simulates work by sleeping briefly
+// before completing.
+//
+// Important: the upstream mcp-go server cancels the request context as
+// soon as the synchronous part of the tools/call returns (see
+// request_handler.go:85, `defer cancel()`). Task goroutines spawned by
+// AddTaskTool inherit that context and therefore see context.Canceled
+// the instant they start. Real-world transports (stdio, SSE, streamable
+// HTTP) don't trip this because they keep the connection — and a
+// background context — alive across the async work, but the in-process
+// transport runs entirely on the request goroutine. To test the polling
+// path realistically we detach from the request context here.
+func newTaskTestInProcessServer(t *testing.T, workDuration time.Duration) *server.MCPServer {
+	t.Helper()
+	srv := server.NewMCPServer("task-test", "1.0.0",
+		server.WithToolCapabilities(true),
+		// list=true, cancel=true, toolCallTasks=true so capability detection,
+		// cancellation, and tool augmentation all flow through.
+		server.WithTaskCapabilities(true, true, true),
+	)
+	srv.AddTaskTool(
+		mcp.Tool{
+			Name:        "long_running",
+			Description: "Sleep, then echo the input string.",
+			InputSchema: mcp.ToolInputSchema{
+				Type: "object",
+				Properties: map[string]any{
+					"msg": map[string]any{"type": "string"},
+				},
+			},
+			Execution: &mcp.ToolExecution{
+				TaskSupport: mcp.TaskSupportRequired,
+			},
+		},
+		func(ctx context.Context, req mcp.CallToolRequest) (*mcp.CreateTaskResult, error) {
+			msg, _ := req.GetArguments()["msg"].(string)
+			// Detach from the request context so the task handler can
+			// outlive the synchronous request — see comment above.
+			time.Sleep(workDuration)
+			_ = ctx
+			return &mcp.CreateTaskResult{
+				Content: []mcp.Content{
+					mcp.TextContent{Type: "text", Text: "echo:" + msg},
+				},
+			}, nil
+		},
+	)
+	return srv
+}
+
+// newSyncOnlyServer is a server that does NOT advertise task capability.
+// Used to verify the auto-detect path keeps the sync semantics.
+func newSyncOnlyServer() *server.MCPServer {
+	srv := server.NewMCPServer("sync-only", "1.0.0",
+		server.WithToolCapabilities(true),
+	)
+	srv.AddTool(
+		mcp.NewTool("greet",
+			mcp.WithDescription("Say hello"),
+			mcp.WithString("name", mcp.Required()),
+		),
+		func(ctx context.Context, req mcp.CallToolRequest) (*mcp.CallToolResult, error) {
+			name, _ := req.GetArguments()["name"].(string)
+			return mcp.NewToolResultText("hi " + name), nil
+		},
+	)
+	return srv
+}
+
+func TestConnectionPoolAdvertisesTaskCapability(t *testing.T) {
+	pool := NewMCPConnectionPool(DefaultConnectionPoolConfig(), false, nil, nil)
+	defer func() { _ = pool.Close() }()
+
+	srv := newTaskTestInProcessServer(t, 0)
+	cfg := config.MCPServerConfig{Type: "inprocess", InProcessServer: srv}
+
+	conn, err := pool.GetConnection(context.Background(), "tasks", cfg)
+	if err != nil {
+		t.Fatalf("GetConnection: %v", err)
+	}
+
+	init := conn.InitializeResult()
+	if init == nil {
+		t.Fatal("InitializeResult is nil after GetConnection")
+	}
+	if init.Capabilities.Tasks == nil {
+		t.Fatal("server did not advertise Tasks capability — initialize handshake regressed")
+	}
+	if !conn.SupportsToolTasks() {
+		t.Error("SupportsToolTasks should be true for a server with toolCallTasks=true")
+	}
+	if !pool.ServerSupportsToolTasks("tasks") {
+		t.Error("ServerSupportsToolTasks should mirror the connection's value")
+	}
+}
+
+func TestConnectionPoolDetectsAbsentTaskCapability(t *testing.T) {
+	pool := NewMCPConnectionPool(DefaultConnectionPoolConfig(), false, nil, nil)
+	defer func() { _ = pool.Close() }()
+
+	cfg := config.MCPServerConfig{Type: "inprocess", InProcessServer: newSyncOnlyServer()}
+	conn, err := pool.GetConnection(context.Background(), "sync", cfg)
+	if err != nil {
+		t.Fatalf("GetConnection: %v", err)
+	}
+	if conn.SupportsToolTasks() {
+		t.Error("SupportsToolTasks should be false for a server that didn't advertise the capability")
+	}
+}
+
+func TestSupportsToolTasksFromInit(t *testing.T) {
+	cases := []struct {
+		name string
+		in   *mcp.InitializeResult
+		want bool
+	}{
+		{"nil", nil, false},
+		{"no tasks", &mcp.InitializeResult{}, false},
+		{"tasks no requests", &mcp.InitializeResult{
+			Capabilities: mcp.ServerCapabilities{Tasks: &mcp.TasksCapability{}},
+		}, false},
+		{"tasks with toolCalls", &mcp.InitializeResult{
+			Capabilities: mcp.ServerCapabilities{Tasks: mcp.NewTasksCapability()},
+		}, true},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			if got := supportsToolTasksFromInit(tc.in); got != tc.want {
+				t.Errorf("supportsToolTasksFromInit() = %v, want %v", got, tc.want)
+			}
+		})
+	}
+}
+
+func TestParseTaskMode(t *testing.T) {
+	cases := []struct {
+		in   string
+		want MCPTaskMode
+	}{
+		{"", MCPTaskModeAuto},
+		{"auto", MCPTaskModeAuto},
+		{"AUTO", MCPTaskModeAuto},
+		{"never", MCPTaskModeNever},
+		{"off", MCPTaskModeNever},
+		{"always", MCPTaskModeAlways},
+		{"force", MCPTaskModeAlways},
+		{"bogus", MCPTaskModeAuto},
+	}
+	for _, tc := range cases {
+		if got := ParseTaskMode(tc.in); got != tc.want {
+			t.Errorf("ParseTaskMode(%q) = %q, want %q", tc.in, got, tc.want)
+		}
+	}
+}
+
+func TestExecuteToolPollsTaskToCompletion(t *testing.T) {
+	mgr := NewMCPToolManager()
+	mgr.SetTaskConfig(MCPTaskConfig{
+		PollInterval:    20 * time.Millisecond,
+		MaxPollInterval: 50 * time.Millisecond,
+		Timeout:         10 * time.Second,
+	})
+
+	cfg := config.MCPServerConfig{
+		Type:            "inprocess",
+		InProcessServer: newTaskTestInProcessServer(t, 50*time.Millisecond),
+	}
+
+	if _, err := mgr.AddServer(context.Background(), "tasks", cfg); err != nil {
+		t.Fatalf("AddServer: %v", err)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	res, err := mgr.ExecuteTool(ctx, "tasks__long_running", `{"msg":"hello"}`)
+	if err != nil {
+		t.Fatalf("ExecuteTool: %v", err)
+	}
+	if res.IsError {
+		t.Fatalf("expected non-error result, got %s", res.Content)
+	}
+	if !strings.Contains(res.Content, "echo:hello") {
+		t.Errorf("expected result to contain 'echo:hello', got %s", res.Content)
+	}
+}
+
+func TestExecuteToolHonorsNeverMode(t *testing.T) {
+	// Even though the server advertises tasks/toolCalls, "never" should
+	// keep the call synchronous. Since the tool is TaskSupportRequired,
+	// the server returns an error rather than running it sync — we just
+	// verify the error surfaces (not a poll-loop hang).
+	mgr := NewMCPToolManager()
+	mgr.SetTaskConfig(MCPTaskConfig{
+		PerServerMode: map[string]MCPTaskMode{"tasks": MCPTaskModeNever},
+		Timeout:       2 * time.Second,
+	})
+
+	cfg := config.MCPServerConfig{
+		Type:            "inprocess",
+		InProcessServer: newTaskTestInProcessServer(t, 0),
+	}
+
+	if _, err := mgr.AddServer(context.Background(), "tasks", cfg); err != nil {
+		t.Fatalf("AddServer: %v", err)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
+	defer cancel()
+
+	// We don't care which way the server fails the sync call; we just want
+	// to confirm we didn't hang in the polling loop and didn't panic.
+	_, err := mgr.ExecuteTool(ctx, "tasks__long_running", `{"msg":"x"}`)
+	if err == nil {
+		t.Fatal("expected an error when forcing sync execution of a task-required tool")
+	}
+}
+
+func TestExecuteToolEmitsProgress(t *testing.T) {
+	var statuses []mcp.TaskStatus
+	mgr := NewMCPToolManager()
+	mgr.SetTaskConfig(MCPTaskConfig{
+		PollInterval:    10 * time.Millisecond,
+		MaxPollInterval: 25 * time.Millisecond,
+		Timeout:         5 * time.Second,
+		Progress: func(p MCPTaskProgress) {
+			statuses = append(statuses, p.Status)
+		},
+	})
+
+	cfg := config.MCPServerConfig{
+		Type:            "inprocess",
+		InProcessServer: newTaskTestInProcessServer(t, 30*time.Millisecond),
+	}
+	if _, err := mgr.AddServer(context.Background(), "tasks", cfg); err != nil {
+		t.Fatalf("AddServer: %v", err)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	if _, err := mgr.ExecuteTool(ctx, "tasks__long_running", `{"msg":"hi"}`); err != nil {
+		t.Fatalf("ExecuteTool: %v", err)
+	}
+	if len(statuses) == 0 {
+		t.Fatal("expected at least one progress event")
+	}
+	last := statuses[len(statuses)-1]
+	if !last.IsTerminal() {
+		t.Errorf("last progress event should be terminal, got %q", last)
+	}
+}
+
+func TestListGetCancelMCPTasksOnLoadedServer(t *testing.T) {
+	mgr := NewMCPToolManager()
+	cfg := config.MCPServerConfig{
+		Type:            "inprocess",
+		InProcessServer: newTaskTestInProcessServer(t, 0),
+	}
+	if _, err := mgr.AddServer(context.Background(), "tasks", cfg); err != nil {
+		t.Fatalf("AddServer: %v", err)
+	}
+
+	ctx := context.Background()
+
+	// tasks/list — no in-flight tasks yet, so we just verify the call
+	// succeeds and returns an empty slice (or any slice; the exact length
+	// depends on server retention policy).
+	if _, err := mgr.ListServerTasks(ctx, "tasks"); err != nil {
+		t.Errorf("ListServerTasks: %v", err)
+	}
+
+	// Unknown server should error cleanly without panicking.
+	if _, err := mgr.GetServerTask(ctx, "unknown", "abc"); err == nil {
+		t.Error("GetServerTask on unknown server should error")
+	}
+	if _, err := mgr.CancelServerTask(ctx, "unknown", "abc"); err == nil {
+		t.Error("CancelServerTask on unknown server should error")
+	}
+}

internal/ui/block_renderer.go

@@ -28,15 +28,6 @@ type blockRenderer struct {
 // renderingOption configures block rendering
 type renderingOption func(*blockRenderer)
 
-// WithFullWidth returns a renderingOption that configures the block renderer
-// to expand to the full available width of its container. When enabled, the
-// block will fill the entire horizontal space rather than sizing to its content.
-func WithFullWidth() renderingOption {
-	return func(c *blockRenderer) {
-		c.fullWidth = true
-	}
-}
-
 // WithNoBorder returns a renderingOption that disables all borders on the
 // block, rendering content with only padding.
 func WithNoBorder() renderingOption {
@@ -63,15 +54,6 @@ func WithBorderColor(c color.Color) renderingOption {
 	}
 }
 
-// WithMarginTop returns a renderingOption that sets the top margin
-// for the block. The margin is specified in number of lines and adds
-// vertical space above the block.
-func WithMarginTop(margin int) renderingOption {
-	return func(c *blockRenderer) {
-		c.marginTop = margin
-	}
-}
-
 // WithMarginBottom returns a renderingOption that sets the bottom margin
 // for the block. The margin is specified in number of lines and adds
 // vertical space below the block.
@@ -81,24 +63,6 @@ func WithMarginBottom(margin int) renderingOption {
 	}
 }
 
-// WithPaddingLeft returns a renderingOption that sets the left padding
-// for the block content. The padding is specified in number of characters
-// and adds horizontal space between the left border and the content.
-func WithPaddingLeft(padding int) renderingOption {
-	return func(c *blockRenderer) {
-		c.paddingLeft = padding
-	}
-}
-
-// WithPaddingRight returns a renderingOption that sets the right padding
-// for the block content. The padding is specified in number of characters
-// and adds horizontal space between the content and the right border.
-func WithPaddingRight(padding int) renderingOption {
-	return func(c *blockRenderer) {
-		c.paddingRight = padding
-	}
-}
-
 // WithPaddingTop returns a renderingOption that sets the top padding
 // for the block content. The padding is specified in number of lines
 // and adds vertical space between the top border and the content.
@@ -117,33 +81,6 @@ func WithPaddingBottom(padding int) renderingOption {
 	}
 }
 
-// WithBackground returns a renderingOption that sets the background color
-// for the entire block. The color parameter accepts any color.Color value,
-// typically a lipgloss hex color (e.g. lipgloss.Color("#1e1e2e")).
-func WithBackground(c color.Color) renderingOption {
-	return func(br *blockRenderer) {
-		br.background = &c
-	}
-}
-
-// WithForeground returns a renderingOption that overrides the default text
-// foreground color (theme.Text) for the block. Useful for muted or
-// de-emphasized content blocks.
-func WithForeground(c color.Color) renderingOption {
-	return func(br *blockRenderer) {
-		br.foreground = &c
-	}
-}
-
-// WithWidth returns a renderingOption that sets a specific width for the block
-// in characters. This overrides the default container width and allows precise
-// control over the block's horizontal dimensions.
-func WithWidth(width int) renderingOption {
-	return func(c *blockRenderer) {
-		c.width = width
-	}
-}
-
 // renderContentBlock renders content with configurable styling options
 func renderContentBlock(content string, containerWidth int, options ...renderingOption) string {
 	renderer := &blockRenderer{

internal/ui/cli.go

@@ -54,12 +54,6 @@ func (c *CLI) GetUsageTracker() *UsageTracker {
 	return c.usageTracker
 }
 
-// GetDebugLogger returns a CLIDebugLogger instance that routes debug output
-// through the CLI's rendering system for consistent message formatting and display.
-func (c *CLI) GetDebugLogger() *CLIDebugLogger {
-	return NewCLIDebugLogger(c)
-}
-
 // SetModelName updates the current AI model name being used in the conversation.
 // This name is displayed in message headers to indicate which model is responding.
 func (c *CLI) SetModelName(modelName string) {
@@ -87,13 +81,6 @@ func (c *CLI) DisplayUserMessage(message string) {
 	fmt.Println(c.renderer.RenderUserMessage(message, time.Now()).Content)
 }
 
-// DisplayAssistantMessage renders and displays an AI assistant's response message
-// with appropriate formatting. This method delegates to DisplayAssistantMessageWithModel
-// with an empty model name for backward compatibility.
-func (c *CLI) DisplayAssistantMessage(message string) error {
-	return c.DisplayAssistantMessageWithModel(message, "")
-}
-
 // DisplayAssistantMessageWithModel renders and displays an AI assistant's response
 // with the specified model name shown in the message header. The message is
 // formatted according to the current display mode and includes timestamp information.
@@ -149,12 +136,6 @@ func (c *CLI) DisplayExtensionBlock(text, borderColor, subtitle string) {
 	fmt.Println(rendered)
 }
 
-// DisplayCancellation displays a system message indicating that the current
-// AI generation has been cancelled by the user (typically via ESC key).
-func (c *CLI) DisplayCancellation() {
-	fmt.Println(c.renderer.RenderSystemMessage("Generation cancelled by user (ESC pressed)", time.Now()).Content)
-}
-
 // DisplayDebugMessage renders and displays a debug message if debug mode is enabled.
 // Debug messages are formatted distinctively and only shown when the CLI is
 // initialized with debug=true.

internal/ui/commands/commands.go

@@ -161,6 +161,12 @@ var SlashCommands = []SlashCommand{
 		Category:    "Navigation",
 		Aliases:     []string{"/r"},
 	},
+	{
+		Name:        "/copy",
+		Description: "Copy the last message to the system clipboard",
+		Category:    "System",
+		Aliases:     []string{"/cp"},
+	},
 	{
 		Name:        "/export",
 		Description: "Export session (JSONL by default, or /export path.jsonl)",
@@ -199,18 +205,6 @@ func GetCommandByName(name string) *SlashCommand {
 	return nil
 }
 
-// GetAllCommandNames returns a complete list of all command names and their aliases.
-// This is useful for command completion, validation, and help display. The returned
-// slice contains both primary command names and all alternative aliases.
-func GetAllCommandNames() []string {
-	var names []string
-	for _, cmd := range SlashCommands {
-		names = append(names, cmd.Name)
-		names = append(names, cmd.Aliases...)
-	}
-	return names
-}
-
 // ExtensionCommand is a slash command registered by an extension. Unlike
 // built-in SlashCommands whose execution is hardcoded in handleSlashCommand,
 // extension commands carry their own Execute callback.

internal/ui/debug_logger.go

@@ -1,79 +0,0 @@
-package ui
-
-import (
-	"fmt"
-	"strings"
-	"time"
-)
-
-// CLIDebugLogger implements the tools.DebugLogger interface using CLI rendering.
-// It provides debug logging functionality that integrates with the CLI's display
-// system, ensuring debug messages are properly formatted and displayed alongside
-// other conversation content.
-type CLIDebugLogger struct {
-	cli *CLI
-}
-
-// NewCLIDebugLogger creates and returns a new CLIDebugLogger instance that routes
-// debug output through the provided CLI instance. The logger will respect the CLI's
-// debug mode setting and display format preferences.
-func NewCLIDebugLogger(cli *CLI) *CLIDebugLogger {
-	return &CLIDebugLogger{cli: cli}
-}
-
-// LogDebug processes and displays a debug message through the CLI's rendering system.
-// Messages are formatted with appropriate emojis and tags based on their content type
-// (DEBUG, POOL, etc.) and only displayed when debug mode is enabled. The method handles
-// multi-line debug output and connection pool status messages with context-aware formatting.
-func (l *CLIDebugLogger) LogDebug(message string) {
-	if l.cli == nil || !l.cli.debug {
-		return
-	}
-
-	// Format the message to include all the debug info in a structured way
-	var formattedMessage string
-
-	// Check if this is a multi-line debug output (like connection info)
-	if strings.Contains(message, "[DEBUG]") || strings.Contains(message, "[POOL]") {
-		// Extract the tag and content
-		if after, ok := strings.CutPrefix(message, "[DEBUG]"); ok {
-			content := after
-			content = strings.TrimSpace(content)
-			formattedMessage = fmt.Sprintf("🔍 DEBUG: %s", content)
-		} else if after, ok := strings.CutPrefix(message, "[POOL]"); ok {
-			content := after
-			content = strings.TrimSpace(content)
-
-			// Add appropriate emoji based on the message content
-			if strings.Contains(content, "Creating new connection") {
-				formattedMessage = fmt.Sprintf("🆕 POOL: %s", content)
-			} else if strings.Contains(content, "Created connection") || strings.Contains(content, "Initialized") {
-				formattedMessage = fmt.Sprintf("✅ POOL: %s", content)
-			} else if strings.Contains(content, "Reusing") {
-				formattedMessage = fmt.Sprintf("🔄 POOL: %s", content)
-			} else if strings.Contains(content, "unhealthy") || strings.Contains(content, "failed") {
-				formattedMessage = fmt.Sprintf("❌ POOL: %s", content)
-			} else if strings.Contains(content, "closed") {
-				formattedMessage = fmt.Sprintf("🛑 POOL: %s", content)
-			} else if strings.Contains(content, "Failed to close") {
-				formattedMessage = fmt.Sprintf("⚠️ POOL: %s", content)
-			} else {
-				formattedMessage = fmt.Sprintf("🔍 POOL: %s", content)
-			}
-		} else {
-			formattedMessage = message
-		}
-	} else {
-		formattedMessage = message
-	}
-
-	// Use the CLI's debug message rendering
-	fmt.Println(l.cli.renderer.RenderDebugMessage(formattedMessage, time.Now()).Content)
-}
-
-// IsDebugEnabled checks whether debug logging is currently active. Returns true
-// if the CLI instance exists and has debug mode enabled, allowing callers to
-// conditionally perform expensive debug operations only when necessary.
-func (l *CLIDebugLogger) IsDebugEnabled() bool {
-	return l.cli != nil && l.cli.debug
-}

internal/ui/message_items.go

@@ -25,17 +25,6 @@ type TextMessageItem struct {
 	timestamp   time.Time
 }
 
-// NewTextMessageItem creates a new text message for the scrollback.
-// The content should be pre-rendered using MessageRenderer for proper styling.
-func NewTextMessageItem(id string, role string, content string) *TextMessageItem {
-	return &TextMessageItem{
-		id:        id,
-		role:      role,
-		content:   content,
-		timestamp: time.Now(),
-	}
-}
-
 // NewStyledMessageItem creates a message item with pre-rendered styled content.
 // This is the preferred way to create messages when you have styled content from MessageRenderer.
 func NewStyledMessageItem(id string, role string, rawContent string, preRendered string) *TextMessageItem {
@@ -316,57 +305,6 @@ func (m *StreamingBashOutputItem) MarkComplete() {
 }
 
 // --------------------------------------------------------------------------
-// SystemMessageItem - System messages (commands, info, errors)
-// --------------------------------------------------------------------------
-
-// SystemMessageItem represents a system message (commands, info, errors).
-type SystemMessageItem struct {
-	id           string
-	content      string
-	timestamp    time.Time
-	cachedRender string
-	cachedWidth  int
-}
-
-// NewSystemMessageItem creates a new system message for the scrollback.
-func NewSystemMessageItem(id, content string) *SystemMessageItem {
-	return &SystemMessageItem{
-		id:        id,
-		content:   content,
-		timestamp: time.Now(),
-	}
-}
-
-func (m *SystemMessageItem) ID() string {
-	return m.id
-}
-
-func (m *SystemMessageItem) Render(width int) string {
-	// Return cached render if width matches
-	if m.cachedWidth == width && m.cachedRender != "" {
-		return m.cachedRender
-	}
-
-	// Simple system message formatting
-	rendered := "│ " + strings.ReplaceAll(m.content, "\n", "\n│ ")
-
-	// Cache and return
-	m.cachedRender = rendered
-	m.cachedWidth = width
-	return rendered
-}
-
-func (m *SystemMessageItem) Height() int {
-	if m.cachedRender != "" {
-		return strings.Count(m.cachedRender, "\n") + 1
-	}
-	// Estimate
-	if m.cachedWidth > 0 {
-		return (len(m.content) / max(m.cachedWidth-10, 40)) + 3
-	}
-	return 3
-}
-
 // --------------------------------------------------------------------------
 // Helper: generateMessageID
 // --------------------------------------------------------------------------

internal/ui/messages.go

@@ -88,13 +88,9 @@ func formatToolParams(toolArgs string, maxWidth int) string {
 	}
 
 	bodyKeys := map[string]bool{
-		"content":  true,
-		"old_text": true,
-		"new_text": true,
-		"oldText":  true,
-		"newText":  true,
-		"edits":    true,
-		"todos":    true,
+		"content": true,
+		"edits":   true,
+		"todos":   true,
 	}
 	var remaining []string
 	for key, val := range params {

internal/ui/model.go

@@ -129,8 +129,18 @@ type AppController interface {
 // SkillItem holds display metadata about a loaded skill for the startup
 // [Skills] section. Built by the CLI layer from the SDK's []*kit.Skill.
 type SkillItem struct {
-	Name   string // Skill name (e.g. "btca-cli").
-	Path   string // Absolute path to the skill file.
+	Name        string // Skill name (e.g. "btca-cli").
+	Path        string // Absolute path to the skill file.
+	Source      string // "project" or "user" (global).
+	Description string // Short summary used in autocomplete and help.
+}
+
+// ExtensionItem holds display metadata about a loaded extension for the
+// startup [Extensions] section. Built by the CLI layer from the SDK's
+// []kit.ExtensionInfo.
+type ExtensionItem struct {
+	Name   string // Extension display name (filename without .go extension).
+	Path   string // Absolute path to the extension's .go file.
 	Source string // "project" or "user" (global).
 }
 
@@ -363,6 +373,16 @@ type AppModelOptions struct {
 	// watcher detects changes. May be nil if skill hot-reload is not needed.
 	GetSkillItems func() []SkillItem
 
+	// ExtensionItems lists loaded extensions for the [Extensions] startup
+	// section. Each entry shows the filename of an extension that was
+	// discovered and loaded (global, project-local, or explicit).
+	ExtensionItems []ExtensionItem
+
+	// GetExtensionItems, if non-nil, returns the current extension items.
+	// Called on extension hot-reload to refresh the list. May be nil if no
+	// extensions are loaded.
+	GetExtensionItems func() []ExtensionItem
+
 	// MCPToolCount is the number of tools loaded from external MCP servers.
 	MCPToolCount int
 
@@ -607,6 +627,14 @@ type AppModel struct {
 	// skill list after content hot-reload. May be nil.
 	getSkillItems func() []SkillItem
 
+	// extensionItems lists loaded extensions for the [Extensions] startup
+	// section (filenames only).
+	extensionItems []ExtensionItem
+
+	// getExtensionItems returns the current extension items. Used to refresh
+	// the list after extension hot-reload. May be nil.
+	getExtensionItems func() []ExtensionItem
+
 	// mcpToolCount and extensionToolCount track tool counts by source for
 	// the startup info display.
 	mcpToolCount       int
@@ -860,6 +888,8 @@ func NewAppModel(appCtrl AppController, opts AppModelOptions) *AppModel {
 	m.contextPaths = opts.ContextPaths
 	m.skillItems = opts.SkillItems
 	m.getSkillItems = opts.GetSkillItems
+	m.extensionItems = opts.ExtensionItems
+	m.getExtensionItems = opts.GetExtensionItems
 	m.mcpToolCount = opts.MCPToolCount
 	m.extensionToolCount = opts.ExtensionToolCount
 	m.startupExtensionMessages = opts.StartupExtensionMessages
@@ -912,6 +942,20 @@ func NewAppModel(appCtrl AppController, opts AppModelOptions) *AppModel {
 		}
 	}
 
+	// Merge skills into autocomplete as /skill:<name> commands. Skills accept
+	// optional trailing args, so HasArgs is true — Enter populates the input
+	// with "/skill:name " rather than auto-submitting.
+	if ic, ok := m.input.(*InputComponent); ok && len(opts.SkillItems) > 0 {
+		for _, s := range opts.SkillItems {
+			ic.commands = append(ic.commands, commands.SlashCommand{
+				Name:        "/skill:" + s.Name,
+				Description: formatSkillDescription(s),
+				Category:    "Skills",
+				HasArgs:     true,
+			})
+		}
+	}
+
 	// Merge MCP prompts into autocomplete as /<server>:<prompt> commands.
 	if ic, ok := m.input.(*InputComponent); ok && len(opts.MCPPrompts) > 0 {
 		for _, p := range opts.MCPPrompts {
@@ -1014,8 +1058,21 @@ func (m *AppModel) AddStartupMessageToScrollList() {
 		pairs = append(pairs, [2]string{"Skills", strings.Join(names, ", ")})
 	}
 
-	// Extension tool count (only shown when > 0).
-	if m.extensionToolCount > 0 {
+	// Extensions — listed by filename. Each extension shows its basename
+	// without the .go suffix, matching the [Skills] section's style.
+	if len(m.extensionItems) > 0 {
+		names := make([]string, len(m.extensionItems))
+		for i, ei := range m.extensionItems {
+			names[i] = ei.Name
+		}
+		value := strings.Join(names, ", ")
+		if m.extensionToolCount > 0 {
+			value += fmt.Sprintf(" (%d tools)", m.extensionToolCount)
+		}
+		pairs = append(pairs, [2]string{"Extensions", value})
+	} else if m.extensionToolCount > 0 {
+		// Fallback: tool count only (extensions registered tools but the CLI
+		// did not provide ExtensionItems for some reason).
 		pairs = append(pairs, [2]string{"Extensions", fmt.Sprintf("%d tools", m.extensionToolCount)})
 	}
 
@@ -1251,7 +1308,11 @@ func (m *AppModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			m.scrollList.autoScroll = false
 		case tea.MouseWheelDown:
 			m.scrollList.ScrollBy(scrollLines)
-			if m.scrollList.AtBottom() {
+			// Only re-enable auto-scroll when the user is not actively
+			// selecting text. Otherwise a wheel-down during a drag-select
+			// would re-arm GotoBottom on the next stream chunk, shifting
+			// the highlighted row out from under the cursor.
+			if m.scrollList.AtBottom() && !m.scrollList.IsMouseDown() {
 				m.scrollList.autoScroll = true
 			}
 		}
@@ -1259,9 +1320,14 @@ func (m *AppModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 	// ── Mouse click selection (crush-style character-level) ──────────────────
 	case tea.MouseClickMsg:
 		if msg.Button == tea.MouseLeft {
-			// Calculate viewport-relative coordinates.
-			viewY := msg.Y - m.scrollbackYOffset
-			if viewY >= 0 && viewY < m.scrollList.height {
+			// Compute the scrollback origin from the current frame's layout
+			// rather than the stale cached value from the previous View().
+			// scrollbackYOffset/scrollList.height are only refreshed inside
+			// View() and lag behind any state change that resized the header
+			// (extension widgets, warning rows, etc.) since the last render.
+			yOff, vpHeight := m.currentScrollbackBounds()
+			viewY := msg.Y - yOff
+			if viewY >= 0 && viewY < vpHeight {
 				// Clear any previous selection on a new click.
 				// HandleMouseDown will set up new selection state.
 				if m.scrollList.HandleMouseDown(msg.X, viewY) {
@@ -1272,8 +1338,9 @@ func (m *AppModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 
 	// ── Mouse motion/drag for character-level selection ──────────────────────
 	case tea.MouseMotionMsg:
-		viewY := msg.Y - m.scrollbackYOffset
-		if viewY >= 0 && viewY < m.scrollList.height {
+		yOff, vpHeight := m.currentScrollbackBounds()
+		viewY := msg.Y - yOff
+		if viewY >= 0 && viewY < vpHeight {
 			m.scrollList.HandleMouseDrag(msg.X, viewY)
 		}
 
@@ -1603,10 +1670,16 @@ func (m *AppModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 
 	// ── Cancel timer expired ─────────────────────────────────────────────────
 	case uicore.CancelTimerExpiredMsg:
+		if m.canceling {
+			m.layoutDirty = true
+		}
 		m.canceling = false
 
 	// ── Ctrl+C reset timer expired ────────────────────────────────────────────
 	case uicore.CtrlCResetMsg:
+		if m.ctrlCPressedOnce {
+			m.layoutDirty = true
+		}
 		m.ctrlCPressedOnce = false
 
 	// ── Input submitted ──────────────────────────────────────────────────────
@@ -2328,6 +2401,7 @@ func (m *AppModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		if msg.err != nil {
 			m.printSystemMessage(fmt.Sprintf("Extension reload failed: %v", msg.err))
 		} else {
+			m.refreshExtensionItems()
 			m.printSystemMessage("Extensions reloaded.")
 		}
 
@@ -3095,6 +3169,8 @@ func (m *AppModel) handleSlashCommand(sc *commands.SlashCommand, args string) te
 		return m.handleResumeCommand()
 	case "/export":
 		return m.handleExportCommand(args)
+	case "/copy":
+		return m.handleCopyCommand()
 	case "/share":
 		return m.handleShareCommand()
 	case "/import":
@@ -3395,13 +3471,56 @@ func (m *AppModel) refreshPromptTemplates() {
 	}
 }
 
-// refreshSkillItems reloads skill items from the provider callback.
-// Called on ContentReloadEvent.
+// refreshSkillItems reloads skill items from the provider callback and
+// updates the autocomplete entries. Called on ContentReloadEvent.
 func (m *AppModel) refreshSkillItems() {
 	if m.getSkillItems == nil {
 		return
 	}
-	m.skillItems = m.getSkillItems()
+	newItems := m.getSkillItems()
+	m.skillItems = newItems
+
+	if ic, ok := m.input.(*InputComponent); ok {
+		// Remove old Skills commands and add fresh ones.
+		var kept []commands.SlashCommand
+		for _, sc := range ic.commands {
+			if sc.Category != "Skills" {
+				kept = append(kept, sc)
+			}
+		}
+		for _, s := range newItems {
+			kept = append(kept, commands.SlashCommand{
+				Name:        "/skill:" + s.Name,
+				Description: formatSkillDescription(s),
+				Category:    "Skills",
+				HasArgs:     true,
+			})
+		}
+		ic.commands = kept
+	}
+}
+
+// refreshExtensionItems reloads extension items from the provider callback
+// so the [Extensions] startup section reflects the current set after a
+// hot-reload. Called from the extReloadResultMsg handler.
+func (m *AppModel) refreshExtensionItems() {
+	if m.getExtensionItems == nil {
+		return
+	}
+	m.extensionItems = m.getExtensionItems()
+}
+
+// formatSkillDescription returns the autocomplete description for a skill,
+// prefixed with [project] or [user] so users can tell colliding names apart.
+func formatSkillDescription(s SkillItem) string {
+	prefix := "[user]"
+	if s.Source == "project" {
+		prefix = "[project]"
+	}
+	if s.Description == "" {
+		return prefix
+	}
+	return prefix + " " + s.Description
 }
 
 // refreshMCPPrompts reloads MCP prompts from the provider callback and
@@ -3476,6 +3595,7 @@ func (m *AppModel) printHelpMessage() {
 		"**System:**\n" +
 		"- `/compact [instructions]`: Summarise older messages to free context space\n" +
 		"- `/clear`: Clear message history\n" +
+		"- `/copy`: Copy the last message to the system clipboard\n" +
 		"- `/export [path]`: Export session as JSONL\n" +
 		"- `/import <path.jsonl>`: Import session from JSONL file\n" +
 		"- `/reset-usage`: Reset usage statistics\n" +
@@ -3712,7 +3832,12 @@ func (m *AppModel) appendStreamingChunk(role, content string) {
 		}
 		// Auto-scroll to bottom if enabled (iteratr pattern)
 		// Don't call SetItems() - the slice reference hasn't changed
-		if m.scrollList != nil {
+		//
+		// CRITICAL: never scroll the viewport while the user is actively
+		// selecting text (mouse button held). Doing so shifts the
+		// highlighted content out from under the cursor and produces the
+		// off-by-N-row drift users see when copy-selecting during streaming.
+		if m.scrollList != nil && !m.scrollList.IsMouseDown() {
 			if m.scrollList.autoScroll {
 				m.scrollList.GotoBottom()
 			} else if m.scrollList.AtBottom() {
@@ -3740,6 +3865,36 @@ func (m *AppModel) appendStreamingChunk(role, content string) {
 	m.refreshContent()
 }
 
+// currentScrollbackBounds returns the live (yOffset, viewportHeight) for the
+// scrollback region, computed from the current state — not from the cached
+// values populated inside View().
+//
+// scrollbackYOffset and scrollList.height are refreshed once per render, so
+// any state change that resizes the header (extension widget toggles,
+// warning rows, queued messages, etc.) leaves the cached values one frame
+// stale. Mouse click handlers in Update() can then place the cursor on the
+// wrong line, producing the off-by-N-row drift seen during copy-selection.
+//
+// This recomputes the header height by rendering it (cheap — the renderer
+// returns "" when no extension header is set) and recomputes the viewport
+// height the same way distributeHeight() does, so both inputs to the
+// y → (item, line) mapping are always current.
+func (m *AppModel) currentScrollbackBounds() (yOffset, viewportHeight int) {
+	// Force a fresh layout if anything in Update() marked the state dirty;
+	// otherwise scrollList.height still reflects the previous frame.
+	if m.layoutDirty {
+		m.distributeHeight()
+		m.layoutDirty = false
+	}
+	if headerView := m.renderHeaderFooter(m.getHeader); headerView != "" {
+		yOffset = lipgloss.Height(headerView)
+	}
+	if m.scrollList != nil {
+		viewportHeight = m.scrollList.height
+	}
+	return yOffset, viewportHeight
+}
+
 // distributeHeight recalculates child component heights after a window resize,
 // queue change, widget update, or state transition, and propagates the computed
 // stream height to the StreamComponent.
@@ -3812,7 +3967,20 @@ func (m *AppModel) distributeHeight() {
 		headerFooterLines += lipgloss.Height(footerView)
 	}
 
-	streamHeight := max(m.height-separatorLines-widgetLines-headerFooterLines-queuedLines-inputLines-statusBarLines, 0)
+	// Account for transient warning rows that View() injects between the
+	// scrollback and the separator. These flags are toggled by ESC/Ctrl+C
+	// handlers; without subtracting them here the joined view exceeds
+	// m.height by one line per active warning and the bottom of the screen
+	// gets silently clipped — which in turn invalidates scrollbackYOffset.
+	var warningLines int
+	if m.canceling {
+		warningLines++
+	}
+	if m.ctrlCPressedOnce {
+		warningLines++
+	}
+
+	streamHeight := max(m.height-separatorLines-widgetLines-headerFooterLines-queuedLines-inputLines-statusBarLines-warningLines, 0)
 
 	// In alt screen mode, give the calculated height to ScrollList instead of stream.
 	// The stream component still exists but is embedded as the last item in scrollList.
@@ -4236,6 +4404,48 @@ func (m *AppModel) handleNameCommand(args string) tea.Cmd {
 	return nil
 }
 
+// handleCopyCommand copies the last user or assistant message to the system
+// clipboard. Skips transient system messages (e.g. /help output) so the user
+// gets the actual last conversational message.
+func (m *AppModel) handleCopyCommand() tea.Cmd {
+	if len(m.messages) == 0 {
+		m.printSystemMessage("No messages to copy.")
+		return nil
+	}
+
+	var (
+		text string
+		role string
+	)
+	for i := len(m.messages) - 1; i >= 0; i-- {
+		switch msg := m.messages[i].(type) {
+		case *TextMessageItem:
+			if msg.role == "user" || msg.role == "assistant" {
+				text = msg.content
+				role = msg.role
+			}
+		case *StreamingMessageItem:
+			if msg.role == "assistant" || msg.role == "reasoning" {
+				text = msg.content.String()
+				role = msg.role
+			}
+		}
+		if text != "" {
+			break
+		}
+	}
+
+	if strings.TrimSpace(text) == "" {
+		m.printSystemMessage("No copyable message found.")
+		return nil
+	}
+
+	m.printSystemMessage(fmt.Sprintf(
+		"Copied last %s message to clipboard (%d chars).", role, len(text),
+	))
+	return clipboard.CopyToClipboard(text)
+}
+
 // handleExportCommand exports the current session to a file.
 // Usage: /export          — copies the JSONL file to cwd with a descriptive name.
 //

internal/ui/render/blocks.go

@@ -19,28 +19,7 @@ import (
 //   - @path/to/file.txt      (unquoted, no spaces)
 var fileTokenPattern = regexp.MustCompile(`@"[^"]+"|@[^\s]+`)
 
-// UserBlock renders a user message with herald Tip styling.
-// The width parameter controls line wrapping so long messages don't overflow.
-// Any @file tokens in the content are highlighted with the theme accent color.
-func UserBlock(content string, width int, ty *herald.Typography, theme style.Theme) string {
-	if strings.TrimSpace(content) == "" {
-		content = "(empty message)"
-	}
-
-	// Wrap content before passing to herald Alert so long lines break
-	// inside the alert box. Subtract 4 to account for the alert bar
-	// prefix ("│ ") and a small margin.
-	if width > 4 {
-		content = lipgloss.Wrap(content, width-4, "")
-	}
-
-	// Highlight @file tokens with accent color so file references are
-	// visually distinct from surrounding prompt text.
-	content = HighlightFileTokens(content, theme)
-
-	rendered := ty.Tip(content)
-	return styleMarginBottom(theme, rendered)
-}
+// UserBlock-related rendering helpers and herald typography.
 
 // HighlightFileTokens wraps @file tokens in the given text with the theme
 // accent color so they stand out visually in rendered user messages.
@@ -154,44 +133,6 @@ func ErrorBlock(errorMsg string, ty *herald.Typography, theme style.Theme) strin
 	return styleMarginBottom(theme, rendered)
 }
 
-// ToolBlock renders a tool execution result with header and body.
-func ToolBlock(displayName, params, body string, isError bool, width int, ty *herald.Typography, theme style.Theme) string {
-	var icon string
-	iconColor := theme.Success
-	if isError {
-		icon = "×"
-		iconColor = theme.Error
-	} else {
-		icon = "✓"
-	}
-
-	// Style the tool name with color
-	nameColor := theme.Info
-	if isError {
-		nameColor = theme.Error
-	}
-	styledName := lipgloss.NewStyle().Foreground(nameColor).Bold(true).Render(displayName)
-	styledIcon := lipgloss.NewStyle().Foreground(iconColor).Render(icon)
-
-	// Build the content: icon + name + params on first line, then body
-	headerLine := styledIcon + " " + styledName
-	if params != "" {
-		headerLine += " " + lipgloss.NewStyle().Foreground(theme.Muted).Render(params)
-	}
-
-	if strings.TrimSpace(body) == "" {
-		body = ty.Italic("(no output)")
-	}
-
-	// Compose: icon + name + params, then body
-	fullContent := ty.Compose(
-		headerLine,
-		"",
-		body,
-	)
-	return styleMarginBottom(theme, fullContent)
-}
-
 // styleMarginBottom applies a 1-line margin bottom using the theme.
 func styleMarginBottom(theme style.Theme, content string) string {
 	return style.GetCachedStyles().MarginBottom1.Render(content)

internal/ui/render/blocks_test.go

@@ -4,30 +4,9 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/indaco/herald"
-
 	"github.com/mark3labs/kit/internal/ui/style"
 )
 
-// testTypography creates a herald Typography for tests.
-func testTypography(theme style.Theme) *herald.Typography {
-	return herald.New(
-		herald.WithPalette(herald.ColorPalette{
-			Primary:   theme.Primary,
-			Secondary: theme.Secondary,
-			Tertiary:  theme.Info,
-			Accent:    theme.Accent,
-			Highlight: theme.Highlight,
-			Muted:     theme.Muted,
-			Text:      theme.Text,
-			Surface:   theme.Background,
-			Base:      theme.CodeBg,
-		}),
-		herald.WithAlertLabel(herald.AlertTip, ""),
-		herald.WithAlertIcon(herald.AlertTip, ""),
-	)
-}
-
 func TestHighlightFileTokens(t *testing.T) {
 	theme := style.DefaultTheme()
 
@@ -88,24 +67,25 @@ func TestHighlightFileTokens(t *testing.T) {
 	}
 }
 
-func TestUserBlockHighlightsFileTokens(t *testing.T) {
+// TestHighlightFileTokensInjectsANSI verifies that HighlightFileTokens
+// preserves the original @file references in the output and wraps each
+// token with ANSI escape codes for the theme accent color.
+func TestHighlightFileTokensInjectsANSI(t *testing.T) {
 	theme := style.DefaultTheme()
-	ty := testTypography(theme)
 
-	// A user message with @file tokens should contain ANSI escapes around the token.
 	content := "refactor @main.go and @utils.go"
-	result := UserBlock(content, 80, ty, theme)
+	result := HighlightFileTokens(content, theme)
 
-	// The rendered output should contain both file references.
+	// The output should still contain both file references.
 	if !strings.Contains(result, "@main.go") {
-		t.Errorf("UserBlock output should contain @main.go, got:\n%s", result)
+		t.Errorf("HighlightFileTokens output should contain @main.go, got:\n%s", result)
 	}
 	if !strings.Contains(result, "@utils.go") {
-		t.Errorf("UserBlock output should contain @utils.go, got:\n%s", result)
+		t.Errorf("HighlightFileTokens output should contain @utils.go, got:\n%s", result)
 	}
 
 	// Verify ANSI codes are present (the tokens are styled).
 	if !strings.Contains(result, "\x1b[") {
-		t.Errorf("UserBlock output should contain ANSI escape codes for styled @file tokens")
+		t.Errorf("HighlightFileTokens output should contain ANSI escape codes for styled @file tokens")
 	}
 }

internal/ui/scrolllist.go

@@ -60,10 +60,13 @@ func NewScrollList(width, height int) *ScrollList {
 }
 
 // SetItems replaces the items in the scroll list. If auto-scroll is enabled,
-// the viewport will scroll to the bottom to show the latest content.
+// the viewport will scroll to the bottom to show the latest content — EXCEPT
+// when the user is actively selecting text (mouse button held), in which case
+// the scroll position is locked so the highlighted content stays under the
+// cursor. The pending bottom-scroll is deferred to MouseUp.
 func (s *ScrollList) SetItems(items []MessageItem) {
 	s.items = items
-	if s.autoScroll {
+	if s.autoScroll && !s.sel.MouseDown {
 		s.GotoBottom()
 	}
 }
@@ -157,6 +160,10 @@ func (s *ScrollList) HandleMouseDown(x, y int) bool {
 // HandleMouseDrag handles mouse motion while button is held.
 // Updates the selection endpoint for character-level precision.
 // Returns true if selection was updated.
+//
+// Defensively disables auto-scroll on every drag update — even if the
+// MouseDown handler missed (e.g. click landed in viewport padding), any
+// active drag means the user is selecting and the viewport must not jump.
 func (s *ScrollList) HandleMouseDrag(x, y int) bool {
 	if !s.sel.MouseDown {
 		return false
@@ -171,6 +178,9 @@ func (s *ScrollList) HandleMouseDrag(x, y int) bool {
 		return false
 	}
 
+	// Hard-lock the viewport while dragging.
+	s.autoScroll = false
+
 	s.sel.DragItemIdx = itemIdx
 	s.sel.DragLineIdx = lineIdx
 	s.sel.DragCol = x
@@ -178,6 +188,13 @@ func (s *ScrollList) HandleMouseDrag(x, y int) bool {
 	return true
 }
 
+// IsMouseDown reports whether the user currently has the mouse button held
+// (i.e. a selection drag is in progress). Used by the parent model to avoid
+// re-enabling auto-scroll during streaming while the user is selecting.
+func (s *ScrollList) IsMouseDown() bool {
+	return s.sel.MouseDown
+}
+
 // HandleMouseUp handles mouse button release.
 // Returns true if there was an active selection.
 func (s *ScrollList) HandleMouseUp() bool {
@@ -521,6 +538,21 @@ func (s *ScrollList) View() string {
 		for idx := s.offsetIdx; idx < len(s.items) && remainingHeight > 0; idx++ {
 			item := s.items[idx]
 			content := item.Render(s.width)
+
+			// Items that render to an empty string contribute zero height to
+			// the viewport. This MUST match renderedHeight()'s semantics —
+			// otherwise getItemAndLineAtY (which uses renderedHeight) treats
+			// the item as 0 lines while View() emits one blank line via
+			// strings.Split("", "\n") = [""], producing a 1-row downward
+			// drift in mouse hit-testing per empty item between offsetIdx
+			// and the cursor (most visibly streaming-reasoning items before
+			// any reasoning has streamed, which extension widgets surface by
+			// shrinking the scrollback).
+			if content == "" {
+				s.heightCache[item.ID()] = 0
+				continue
+			}
+
 			contentLines := strings.Split(content, "\n")
 
 			// Refresh height cache from the actual render (authoritative).

internal/ui/scrolllist_test.go

@@ -0,0 +1,181 @@
+package ui
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+)
+
+// fakeItem is a deterministic MessageItem for ScrollList tests.
+type fakeItem struct {
+	id    string
+	lines int
+}
+
+func (f *fakeItem) ID() string { return f.id }
+func (f *fakeItem) Render(_ int) string {
+	if f.lines <= 0 {
+		return ""
+	}
+	parts := make([]string, f.lines)
+	for i := range parts {
+		parts[i] = fmt.Sprintf("%s-line-%d", f.id, i)
+	}
+	return strings.Join(parts, "\n")
+}
+func (f *fakeItem) Height() int { return f.lines }
+
+// makeItems builds n fake items of `lines` height each.
+func makeItems(n, lines int) []MessageItem {
+	out := make([]MessageItem, n)
+	for i := range out {
+		out[i] = &fakeItem{id: fmt.Sprintf("item-%d", i), lines: lines}
+	}
+	return out
+}
+
+// TestScrollList_MouseDownPreventsAutoScroll verifies the core fix for the
+// copy-selection drift bug: while the user has the mouse button held
+// (drag-selecting), incoming content updates must NOT shift the viewport,
+// because doing so moves the highlighted content out from under the cursor.
+func TestScrollList_MouseDownPreventsAutoScroll(t *testing.T) {
+	sl := NewScrollList(80, 10)
+	sl.SetItems(makeItems(20, 2)) // 40 lines of content into a 10-line viewport
+	// Capture the auto-scrolled-to-bottom position.
+	startOffsetIdx := sl.offsetIdx
+	startOffsetLine := sl.offsetLine
+
+	// User clicks somewhere in the visible area, starting a drag-select.
+	if !sl.HandleMouseDown(5, 3) {
+		t.Fatalf("HandleMouseDown should accept a click inside the viewport")
+	}
+	if !sl.IsMouseDown() {
+		t.Fatalf("IsMouseDown should be true after HandleMouseDown")
+	}
+
+	// New content arrives. With autoScroll still true, SetItems would
+	// normally call GotoBottom() and shift the viewport. The fix should
+	// suppress that while MouseDown is held.
+	sl.SetItems(makeItems(30, 2)) // 60 lines now
+	if sl.offsetIdx != startOffsetIdx || sl.offsetLine != startOffsetLine {
+		t.Errorf("viewport scrolled during active drag: was (%d,%d), now (%d,%d)",
+			startOffsetIdx, startOffsetLine, sl.offsetIdx, sl.offsetLine)
+	}
+
+	// User releases the mouse — drag is over.
+	sl.HandleMouseUp()
+	if sl.IsMouseDown() {
+		t.Fatalf("IsMouseDown should be false after HandleMouseUp")
+	}
+
+	// After release, a fresh content update should resume auto-scrolling
+	// (move the offset to track the new bottom).
+	afterReleaseIdx := sl.offsetIdx
+	afterReleaseLine := sl.offsetLine
+	sl.SetItems(makeItems(50, 2))
+	if sl.offsetIdx == afterReleaseIdx && sl.offsetLine == afterReleaseLine {
+		t.Errorf("autoscroll did not resume after MouseUp: offset stuck at (%d,%d)",
+			afterReleaseIdx, afterReleaseLine)
+	}
+}
+
+// TestScrollList_DragDisablesAutoScroll verifies that any successful
+// HandleMouseDrag call clears autoScroll, even when HandleMouseDown didn't
+// observe it (e.g. a stale wheel-down event set it back to true mid-stream).
+func TestScrollList_DragDisablesAutoScroll(t *testing.T) {
+	sl := NewScrollList(80, 10)
+	sl.SetItems(makeItems(20, 2))
+
+	// Begin a selection.
+	if !sl.HandleMouseDown(5, 3) {
+		t.Fatalf("HandleMouseDown failed")
+	}
+	// Simulate an external code path that re-enabled autoScroll while
+	// MouseDown is still held (the precise condition that caused drift).
+	sl.autoScroll = true
+
+	// Drag motion should hard-lock the viewport again.
+	if !sl.HandleMouseDrag(10, 4) {
+		t.Fatalf("HandleMouseDrag failed")
+	}
+	if sl.autoScroll {
+		t.Errorf("HandleMouseDrag must clear autoScroll to prevent mid-drag jumps")
+	}
+}
+
+// TestScrollList_SetItemsRespectsMouseDown is the most direct regression
+// test: even with autoScroll enabled and new content appended at the
+// bottom, SetItems must not move the viewport while a mouse drag is in
+// progress. This is what caused the "highlighting shifts by 1+ rows
+// during streaming" symptom reported by the user.
+func TestScrollList_SetItemsRespectsMouseDown(t *testing.T) {
+	sl := NewScrollList(80, 5)
+	sl.SetItems(makeItems(10, 2)) // 20 lines into a 5-line viewport
+	// At bottom.
+	preIdx, preLine := sl.offsetIdx, sl.offsetLine
+
+	// Hold mouse down (no actual drag needed).
+	if !sl.HandleMouseDown(0, 0) {
+		t.Fatalf("HandleMouseDown failed")
+	}
+
+	// Append several more items as if streaming. With the bug, each
+	// SetItems would call GotoBottom and shift the offset.
+	for n := 11; n <= 15; n++ {
+		sl.SetItems(makeItems(n, 2))
+		if sl.offsetIdx != preIdx || sl.offsetLine != preLine {
+			t.Fatalf("viewport drifted during streaming with mouse held: "+
+				"start=(%d,%d) now=(%d,%d) after adding item %d",
+				preIdx, preLine, sl.offsetIdx, sl.offsetLine, n)
+		}
+	}
+}
+
+// TestScrollList_EmptyItemsDoNotShiftMouseMapping is the regression test
+// for the second drift bug: items that render to "" must contribute the
+// same number of rows in View() (zero) as in renderedHeight(), or mouse
+// hit-testing drifts by one row per empty item between offsetIdx and the
+// cursor. This was surfaced by extension widgets (e.g. subagent-monitor)
+// that shrink the scrollback so empty streaming-reasoning items end up
+// in the visible window.
+//
+// Setup: 1 normal item + 1 empty item + 1 normal item. Click on the line
+// where the third item begins. With the bug, getItemAndLineAtY skips the
+// empty item (renderedHeight=0) and reports lineIdx pointing one row
+// past where View() actually painted that line.
+func TestScrollList_EmptyItemsDoNotShiftMouseMapping(t *testing.T) {
+	sl := NewScrollList(80, 10)
+	sl.SetItems([]MessageItem{
+		&fakeItem{id: "a", lines: 2},     // viewY 0–1
+		&fakeItem{id: "empty", lines: 0}, // renders "" — contributes 0 rows
+		&fakeItem{id: "b", lines: 2},     // viewY 2–3
+	})
+
+	// Render the viewport once so the cache reflects what View() actually
+	// emits (this is the path that previously diverged from renderedHeight
+	// for empty items).
+	rendered := sl.View()
+	lines := strings.Split(rendered, "\n")
+
+	// Sanity: View() must emit exactly height lines.
+	if len(lines) != 10 {
+		t.Fatalf("View() returned %d lines, want 10", len(lines))
+	}
+	// Item b's first line should appear at viewY=2, NOT viewY=3.
+	if !strings.Contains(lines[2], "b-line-0") {
+		t.Errorf("viewY=2 should render b-line-0 (empty item contributes 0 rows), got %q", lines[2])
+	}
+
+	// Now the actual hit-test contract: clicking on viewY=2 must map to
+	// item b line 0 — the same coordinate View() rendered there.
+	idx, line := sl.getItemAndLineAtY(2)
+	if idx != 2 || line != 0 {
+		t.Errorf("getItemAndLineAtY(2) = (%d,%d), want (2,0)", idx, line)
+	}
+
+	// And clicking on the second line of b (viewY=3) must map to b line 1.
+	idx, line = sl.getItemAndLineAtY(3)
+	if idx != 2 || line != 1 {
+		t.Errorf("getItemAndLineAtY(3) = (%d,%d), want (2,1)", idx, line)
+	}
+}

internal/ui/selection/selection.go

@@ -230,8 +230,10 @@ func FindWordBoundaries(line string, col int) (startCol, endCol int) {
 
 // HighlightLine applies reverse-video highlighting to a portion of a rendered
 // line (which may contain ANSI escape codes). startCol/endCol are in display
-// columns. If startCol == -1, the entire line is highlighted. If startCol ==
-// endCol, returns the line unchanged.
+// columns. If startCol == -1, the entire line is highlighted. If endCol ==
+// -1, the highlight runs from startCol to the end of the line (the sentinel
+// returned by IsLineInRange for the first line of a multi-line selection).
+// If startCol == endCol, returns the line unchanged.
 //
 // Uses ultraviolet ScreenBuffer for cell-level ANSI manipulation.
 func HighlightLine(line string, startCol, endCol int) string {
@@ -250,6 +252,16 @@ func HighlightLine(line string, startCol, endCol int) string {
 		endCol = lineWidth
 	}
 
+	// "From startCol to end of line" sentinel (returned by IsLineInRange
+	// for the first line of a multi-line selection). Without this branch,
+	// the start line of a multi-line drag would never be highlighted —
+	// the user perceives this as the selection being shifted one row down
+	// from the cursor, especially when extension widgets shrink the
+	// scrollback and make the start line land on a tall styled block.
+	if endCol < 0 {
+		endCol = lineWidth
+	}
+
 	if startCol >= endCol || startCol >= lineWidth {
 		return line
 	}
@@ -296,6 +308,11 @@ func ExtractText(line string, startCol, endCol int) string {
 		endCol = lineWidth
 	}
 
+	// "From startCol to end of line" sentinel (see HighlightLine).
+	if endCol < 0 {
+		endCol = lineWidth
+	}
+
 	if startCol >= endCol || startCol >= lineWidth {
 		return ""
 	}

internal/ui/selection/selection_test.go

@@ -357,6 +357,54 @@ func TestHighlightLine_NoSelection(t *testing.T) {
 	}
 }
 
+// TestHighlightLine_EndOfLineSentinel verifies that endCol=-1 is interpreted
+// as "highlight from startCol to end of line", matching the sentinel
+// returned by IsLineInRange for the first line of a multi-line selection.
+//
+// Regression: without this contract, the start line of any multi-line drag
+// would silently fall through HighlightLine's startCol >= endCol guard and
+// render unstyled, making the selection appear to begin one row below the
+// cursor — the exact "tracking gets shifted" symptom users reported when
+// extension widgets shrank the scrollback enough that the click landed on a
+// styled tool-result block.
+func TestHighlightLine_EndOfLineSentinel(t *testing.T) {
+	line := "Hello, World!"
+	result := HighlightLine(line, 0, -1)
+	if result == line {
+		t.Errorf("endCol=-1 should highlight from startCol to end of line; got unchanged input")
+	}
+	if len(result) <= len(line) {
+		t.Errorf("highlighted result should be longer than plain input (ANSI codes added); got len=%d want > %d", len(result), len(line))
+	}
+}
+
+// TestExtractText_EndOfLineSentinel mirrors TestHighlightLine_EndOfLineSentinel
+// for the extraction path used by the clipboard copy.
+func TestExtractText_EndOfLineSentinel(t *testing.T) {
+	line := "Hello, World!"
+	got := ExtractText(line, 7, -1)
+	want := "World!"
+	if got != want {
+		t.Errorf("ExtractText(line, 7, -1) = %q, want %q", got, want)
+	}
+}
+
+// TestIsLineInRange_StartLineSentinelHighlights composes IsLineInRange with
+// HighlightLine end-to-end: the start line of a multi-line, single-item
+// selection must actually emit highlight ANSI codes. This is the contract
+// the rendering path in scrolllist.View() relies on.
+func TestIsLineInRange_StartLineSentinelHighlights(t *testing.T) {
+	r := Range{StartItemIdx: 5, EndItemIdx: 5, StartLine: 0, EndLine: 2, StartCol: 0, EndCol: 10}
+	inRange, sc, ec := IsLineInRange(r, 5, 0)
+	if !inRange {
+		t.Fatalf("item 5 line 0 should be in range")
+	}
+	highlighted := HighlightLine("first line of selection", sc, ec)
+	if highlighted == "first line of selection" {
+		t.Errorf("first line of multi-line selection was not highlighted (sc=%d ec=%d)", sc, ec)
+	}
+}
+
 // TestMultiClickDetection verifies the click counting logic.
 func TestMultiClickDetection(t *testing.T) {
 	s := NewState()

internal/ui/style/enhanced.go

@@ -211,106 +211,11 @@ func DefaultTheme() Theme {
 	}
 }
 
-// StyleCard creates a lipgloss style for card-like containers with rounded borders,
-// padding, and appropriate width. Used for grouping related content in a visually
-// distinct box.
-func StyleCard(width int, theme Theme) lipgloss.Style {
-	return lipgloss.NewStyle().
-		Width(width).
-		Border(lipgloss.RoundedBorder()).
-		BorderForeground(theme.Border).
-		Padding(1, 2).
-		MarginBottom(1)
-}
-
 // IsDarkBackground returns the cached terminal background detection result.
 func IsDarkBackground() bool {
 	return isDarkBg
 }
 
-// StyleHeader creates a lipgloss style for primary headers using the theme's
-// primary color with bold text for emphasis and hierarchy.
-func StyleHeader(theme Theme) lipgloss.Style {
-	return lipgloss.NewStyle().
-		Foreground(theme.Primary).
-		Bold(true)
-}
-
-// StyleSubheader creates a lipgloss style for secondary headers using the theme's
-// secondary color with bold text, providing visual hierarchy below primary headers.
-func StyleSubheader(theme Theme) lipgloss.Style {
-	return lipgloss.NewStyle().
-		Foreground(theme.Secondary).
-		Bold(true)
-}
-
-// StyleMuted creates a lipgloss style for de-emphasized text using muted colors
-// and italic formatting, suitable for supplementary or less important information.
-func StyleMuted(theme Theme) lipgloss.Style {
-	return lipgloss.NewStyle().
-		Foreground(theme.Muted).
-		Italic(true)
-}
-
-// StyleSuccess creates a lipgloss style for success messages using green colors
-// with bold text to indicate successful operations or positive outcomes.
-func StyleSuccess(theme Theme) lipgloss.Style {
-	return lipgloss.NewStyle().
-		Foreground(theme.Success).
-		Bold(true)
-}
-
-// StyleError creates a lipgloss style for error messages using red colors
-// with bold text to ensure visibility of problems or failures.
-func StyleError(theme Theme) lipgloss.Style {
-	return lipgloss.NewStyle().
-		Foreground(theme.Error).
-		Bold(true)
-}
-
-// StyleWarning creates a lipgloss style for warning messages using yellow/amber
-// colors with bold text to draw attention to potential issues or cautions.
-func StyleWarning(theme Theme) lipgloss.Style {
-	return lipgloss.NewStyle().
-		Foreground(theme.Warning).
-		Bold(true)
-}
-
-// StyleInfo creates a lipgloss style for informational messages using blue colors
-// with bold text for general notifications and status updates.
-func StyleInfo(theme Theme) lipgloss.Style {
-	return lipgloss.NewStyle().
-		Foreground(theme.Info).
-		Bold(true)
-}
-
-// CreateSeparator generates a horizontal separator line with the specified width,
-// character, and color. Useful for visually dividing sections of content in the UI.
-func CreateSeparator(width int, char string, c color.Color) string {
-	return lipgloss.NewStyle().
-		Foreground(c).
-		Width(width).
-		Render(lipgloss.PlaceHorizontal(width, lipgloss.Center, char))
-}
-
-// CreateProgressBar generates a visual progress bar with filled and empty segments
-// based on the percentage complete. The bar uses Unicode block characters for smooth
-// appearance and theme colors to indicate progress.
-func CreateProgressBar(width int, percentage float64, theme Theme) string {
-	filled := int(float64(width) * percentage / 100)
-	empty := width - filled
-
-	filledBar := lipgloss.NewStyle().
-		Foreground(theme.Success).
-		Render(lipgloss.PlaceHorizontal(filled, lipgloss.Left, "█"))
-
-	emptyBar := lipgloss.NewStyle().
-		Foreground(theme.Muted).
-		Render(lipgloss.PlaceHorizontal(empty, lipgloss.Left, "░"))
-
-	return filledBar + emptyBar
-}
-
 // CreateBadge generates a styled badge or label with inverted colors (text on
 // colored background) for highlighting important tags, statuses, or categories.
 func CreateBadge(text string, c color.Color) string {

internal/ui/style/styles.go

@@ -6,13 +6,6 @@ import (
 	heraldmd "github.com/indaco/herald-md"
 )
 
-// BaseStyle returns a new, empty lipgloss style that can be customized with
-// additional styling methods. This serves as the foundation for building more
-// complex styled components.
-func BaseStyle() lipgloss.Style {
-	return lipgloss.NewStyle()
-}
-
 // markdownTypographyCache holds the last-created Typography instance for
 // herald-md rendering. It is cached to avoid re-initialization on every
 // streaming flush tick. The cache is invalidated by SetTheme when the

internal/ui/style/themes.go

@@ -543,12 +543,6 @@ func ApplyThemeWithoutSave(name string) error {
 	return nil
 }
 
-// RefreshThemeRegistry re-scans the themes directory. Call after the user
-// drops a new file into ~/.config/kit/themes/.
-func RefreshThemeRegistry() {
-	initThemeRegistry()
-}
-
 // RegisterThemeFromConfig adds a theme to the runtime registry from an
 // extension's ThemeColorConfig (string hex pairs). Replaces any existing
 // entry with the same name. The theme is immediately available via

internal/ui/tool_approval_input.go

@@ -1,140 +0,0 @@
-package ui
-
-import (
-	"fmt"
-	"strings"
-
-	"charm.land/bubbles/v2/textarea"
-	tea "charm.land/bubbletea/v2"
-	"charm.land/lipgloss/v2"
-)
-
-type ToolApprovalInput struct {
-	textarea textarea.Model
-	toolName string
-	toolArgs string
-	width    int
-	selected bool // true when "yes" is highlighted and false when "no" is
-	approved bool
-	done     bool
-}
-
-func NewToolApprovalInput(toolName, toolArgs string, width int) *ToolApprovalInput {
-	ta := textarea.New()
-	ta.Placeholder = ""
-	ta.ShowLineNumbers = false
-	ta.CharLimit = 0
-	ta.SetWidth(width - 8) // Account for container padding, border and internal padding
-	ta.SetHeight(4)        // Default to 3 lines like huh
-	ta.Focus()
-
-	// Style the textarea using theme colors.
-	theme := GetTheme()
-	styles := ta.Styles()
-	styles.Focused.Base = lipgloss.NewStyle()
-	styles.Focused.Placeholder = lipgloss.NewStyle().Foreground(theme.VeryMuted)
-	styles.Focused.Text = lipgloss.NewStyle().Foreground(theme.Text)
-	styles.Focused.Prompt = lipgloss.NewStyle()
-	styles.Focused.CursorLine = lipgloss.NewStyle()
-	ta.SetStyles(styles)
-
-	return &ToolApprovalInput{
-		textarea: ta,
-		toolName: toolName,
-		toolArgs: toolArgs,
-		width:    width,
-		selected: true,
-	}
-}
-
-func (t *ToolApprovalInput) Init() tea.Cmd {
-	return textarea.Blink
-}
-
-func (t *ToolApprovalInput) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
-	switch msg := msg.(type) {
-	case tea.KeyPressMsg:
-		switch msg.String() {
-		case "y", "Y":
-			t.approved = true
-			t.done = true
-			return t, tea.Quit
-		case "n", "N":
-			t.approved = false
-			t.done = true
-			return t, tea.Quit
-		case "left":
-			t.selected = true
-			return t, nil
-		case "right":
-			t.selected = false
-			return t, nil
-		case "enter":
-			t.approved = t.selected
-			t.done = true
-			return t, tea.Quit
-		case "esc", "ctrl+c":
-			t.approved = false
-			t.done = true
-			return t, tea.Quit
-		}
-	}
-	return t, nil
-}
-
-func (t *ToolApprovalInput) View() tea.View {
-	if t.done {
-		return tea.NewView("we are done")
-	}
-
-	containerStyle := lipgloss.NewStyle()
-
-	theme := GetTheme()
-
-	// PaddingLeft(3) aligns with message content: border(1) + paddingLeft(2).
-	titleStyle := lipgloss.NewStyle().
-		Foreground(theme.Text).
-		MarginBottom(1).
-		PaddingLeft(3)
-
-	// Input box with huh-like styling
-	inputBoxStyle := lipgloss.NewStyle().
-		Border(lipgloss.ThickBorder()).
-		BorderLeft(true).
-		BorderRight(false).
-		BorderTop(false).
-		BorderBottom(false).
-		BorderForeground(theme.Primary).
-		PaddingLeft(2).    // match message block paddingLeft
-		Width(t.width - 1) // full width minus left border
-
-	// Style for the currently selected/highlighted option
-	selectedStyle := lipgloss.NewStyle().
-		Foreground(theme.Success).
-		Bold(true).
-		Underline(true)
-
-	// Style for the unselected/unhighlighted option
-	unselectedStyle := lipgloss.NewStyle().
-		Foreground(theme.VeryMuted)
-
-	// Build the view
-	var view strings.Builder
-	view.WriteString(titleStyle.Render("Allow tool execution"))
-	view.WriteString("\n")
-	details := fmt.Sprintf("Tool: %s\nArguments: %s\n\n", t.toolName, t.toolArgs)
-	view.WriteString(details)
-	view.WriteString("Allow tool execution: ")
-
-	var yesText, noText string
-	if t.selected {
-		yesText = selectedStyle.Render("[y]es")
-		noText = unselectedStyle.Render("[n]o")
-	} else {
-		yesText = unselectedStyle.Render("[y]es")
-		noText = selectedStyle.Render("[n]o")
-	}
-	view.WriteString(yesText + "/" + noText + "\n")
-
-	return tea.NewView(containerStyle.Render(inputBoxStyle.Render(view.String())))
-}

internal/ui/tool_renderers.go

@@ -79,8 +79,7 @@ func renderToolBody(toolName, toolArgs, toolResult string, width int) string {
 // Edit tool — side-by-side diff
 // ---------------------------------------------------------------------------
 
-// renderEditBody renders a side-by-side diff from old_text/new_text in toolArgs.
-// Supports both single-edit mode and multi-edit mode (edits array).
+// renderEditBody renders a side-by-side diff from the edits array in toolArgs.
 func renderEditBody(toolArgs, toolResult string, width int) string {
 	var args map[string]any
 	if err := json.Unmarshal([]byte(toolArgs), &args); err != nil {
@@ -90,35 +89,28 @@ func renderEditBody(toolArgs, toolResult string, width int) string {
 	// Try to extract the starting line number from the unified diff in the result
 	startLine := extractDiffStartLine(toolResult)
 
-	// Check for multi-edit mode (edits array)
-	if editsArr, ok := args["edits"].([]any); ok && len(editsArr) > 0 {
-		var results []string
-		for _, edit := range editsArr {
-			if e, ok := edit.(map[string]any); ok {
-				oldText, _ := e["old_text"].(string)
-				newText, _ := e["new_text"].(string)
-				if oldText != "" || newText != "" {
-					diff := renderDiffBlock(oldText, newText, startLine, width)
-					if diff != "" {
-						results = append(results, diff)
-					}
+	editsArr, ok := args["edits"].([]any)
+	if !ok || len(editsArr) == 0 {
+		return ""
+	}
+
+	var results []string
+	for _, edit := range editsArr {
+		if e, ok := edit.(map[string]any); ok {
+			oldText, _ := e["old_text"].(string)
+			newText, _ := e["new_text"].(string)
+			if oldText != "" || newText != "" {
+				diff := renderDiffBlock(oldText, newText, startLine, width)
+				if diff != "" {
+					results = append(results, diff)
 				}
 			}
 		}
-		if len(results) > 0 {
-			return strings.Join(results, "\n")
-		}
-		return ""
 	}
-
-	// Single-edit mode (legacy)
-	oldText, _ := args["old_text"].(string)
-	newText, _ := args["new_text"].(string)
-	if oldText == "" && newText == "" {
-		return ""
+	if len(results) > 0 {
+		return strings.Join(results, "\n")
 	}
-
-	return renderDiffBlock(oldText, newText, startLine, width)
+	return ""
 }
 
 // extractDiffStartLine parses the first @@ hunk header from a unified diff

pkg/kit/README.md

@@ -190,6 +190,41 @@ msg, err := host.GetMCPPrompt(ctx, "server-name", "prompt-name", map[string]stri
 })
 ```
 
+### MCP Tasks (long-running tools)
+
+Kit advertises [MCP task support](https://modelcontextprotocol.io/specification/2025-11-25/basic/utilities/tasks)
+during `initialize`. Cooperating servers can respond to `tools/call` with a
+`taskId` immediately; Kit then polls `tasks/get` / `tasks/result` until the
+task reaches a terminal state, and best-effort `tasks/cancel`s on context
+cancellation. Servers that don't advertise the capability keep their previous
+synchronous behaviour.
+
+```go
+host, _ := kit.New(ctx, &kit.Options{
+    // Per-server mode: auto (default), never, or always.
+    MCPTaskMode: map[string]kit.MCPTaskMode{
+        "build-server": kit.MCPTaskModeAlways,
+    },
+    MCPTaskTimeout:  15 * time.Minute, // total wall-clock cap
+    MCPTaskProgress: func(p kit.MCPTaskProgress) {
+        log.Printf("%s/%s: %s", p.Server, p.TaskID, p.Status)
+    },
+})
+
+// Inspect / cancel in-flight tasks
+tasks, _ := host.ListMCPTasks(ctx, "build-server")
+t, _    := host.GetMCPTask(ctx, "build-server", tasks[0].TaskID)
+if !t.Status.IsTerminal() {
+    _, _ = host.CancelMCPTask(ctx, "build-server", t.TaskID)
+}
+```
+
+The progress handler fires once when a task is accepted and again on every
+observed status transition; the final invocation always carries a terminal
+status (`MCPTaskStatusCompleted`, `MCPTaskStatusFailed`, or
+`MCPTaskStatusCancelled`). Don't block in the handler — dispatch long work on
+a goroutine.
+
 ### Session Management
 
 Maintain conversation context:
@@ -206,9 +241,46 @@ response, _ := host.Prompt(ctx, "What's my name?")
 host.ClearSession()
 ```
 
+### Runtime Skills and Context Files
+
+For multi-tenant chatbots, web services, or any host that needs per-user or
+per-session instructions, the SDK lets you add, remove, and replace skills and
+project context files (e.g. `AGENTS.md`) **after** Kit construction. Every
+mutation recomposes the system prompt and applies it to the agent so the next
+turn picks up the new instructions — no restart required.
+
+```go
+// Add a programmatic skill (no file on disk required).
+host.AddSkill(&kit.Skill{
+    Name:        "polite-french",
+    Description: "Respond in French and always greet the user.",
+    Content:     "Always reply in French. Open every response with 'Bonjour'.",
+})
+
+// Or load one from disk.
+host.LoadAndAddSkill("/var/skills/refund-policy.md")
+
+// Swap per-user AGENTS.md content fetched from your database.
+host.AddContextFileContent(
+    fmt.Sprintf("session://%s/AGENTS.md", userID),
+    rulesFromDB,
+)
+
+// Tear down session-specific state when the user logs off.
+host.RemoveSkill("polite-french")
+host.RemoveContextFile(fmt.Sprintf("session://%s/AGENTS.md", userID))
+
+// Or replace the whole set in one shot.
+host.SetSkills(activeSkillsForUser)
+host.SetContextFiles(activeContextForUser)
+```
+
+Readers (`GetSkills`, `GetContextFiles`) return snapshots, and every mutator
+is safe to call concurrently from multiple goroutines.
+
 ## Re-exported Types
 
-The SDK re-exports types so you don't need direct internal imports:
+The SDK re-exports message/session/MCP types so you don't need direct internal imports. Agent-configuration types are Kit-owned (not aliases) and use only SDK types in their signatures, so consumers never need to import the underlying LLM-provider package.
 
 ```go
 // Message types
@@ -216,13 +288,28 @@ kit.Message, kit.MessageRole, kit.ContentPart
 kit.TextContent, kit.ReasoningContent, kit.ToolCall, kit.ToolResult, kit.Finish
 kit.RoleUser, kit.RoleAssistant, kit.RoleTool, kit.RoleSystem
 
-// LLM types — concrete Kit-owned structs, no external library dependency
+// LLM types — Kit-owned `LLM*` aliases over the underlying provider types,
+// so consumers never import the provider package directly
 kit.LLMMessage      // {Role LLMMessageRole, Content string}
 kit.LLMMessageRole  // "user" | "assistant" | "system" | "tool"
 kit.LLMUsage        // {InputTokens, OutputTokens, TotalTokens, ...}
 kit.LLMResponse     // {Content, FinishReason, Usage}
 kit.LLMFilePart     // {Filename, Data []byte, MediaType}
 
+// Agent configuration — concrete Kit-owned structs and function types.
+// All fields use SDK types (e.g. `[]kit.Tool`), so consumers can construct
+// these without importing any LLM-provider package.
+kit.AgentConfig              // Lower-level agent config — prefer Options unless you need direct control
+kit.DebugLogger              // Interface: LogDebug(string) / IsDebugEnabled() bool
+kit.MCPTaskConfig            // Task-aware MCP tools/call config (modes, polling, progress)
+kit.ToolCallHandler          // func(toolCallID, toolName, toolArgs string)
+kit.ToolExecutionHandler     // func(toolCallID, toolName, toolArgs string, isStarting bool)
+kit.ToolResultHandler        // func(toolCallID, toolName, toolArgs, result, metadata string, isError bool)
+kit.ResponseHandler          // func(content string)
+kit.StreamingResponseHandler // func(content string)
+kit.ToolCallContentHandler   // func(content string)
+kit.SpinnerFunc              // func(fn func() error) error
+
 // MCP OAuth types
 kit.MCPServer            // *server.MCPServer for in-process MCP transport
 kit.MCPServerConfig      // Configuration for an MCP server (stdio, SSE, or in-process)
@@ -262,6 +349,9 @@ msg  := kit.ConvertFromLLMMessage(lMsg)  // LLMMessage  → SDK Message
 - `ClearSession()` - Clear conversation history
 - `GetSessionPath()` - Get session file path
 - `GetSessionID()` - Get session UUID
+- `AddSkill(*Skill)` / `LoadAndAddSkill(path)` / `RemoveSkill(name)` / `SetSkills([])` - Manage skills at runtime
+- `AddContextFile(*ContextFile)` / `AddContextFileContent(path, content)` / `LoadAndAddContextFile(path)` / `RemoveContextFile(path)` / `SetContextFiles([])` - Manage AGENTS.md-style context files at runtime
+- `RefreshSystemPrompt()` - Re-apply the composed system prompt to the agent
 - `Close()` - Clean up resources
 
 ### Options

pkg/kit/agent_config_internal_test.go

@@ -0,0 +1,208 @@
+package kit
+
+import (
+	"context"
+	"errors"
+	"testing"
+	"time"
+
+	"github.com/mark3labs/kit/internal/agent"
+)
+
+// TestAgentConfigToInternal verifies that the SDK-side AgentConfig converts
+// faithfully to the internal agent.AgentConfig representation, preserving
+// every field consumed by the internal agent layer.
+//
+// Regression test for https://github.com/mark3labs/kit/issues/30.
+func TestAgentConfigToInternal(t *testing.T) {
+	t.Run("nil receiver returns nil", func(t *testing.T) {
+		var c *AgentConfig
+		if got := c.toInternal(); got != nil {
+			t.Errorf("nil.toInternal() = %v, want nil", got)
+		}
+	})
+
+	t.Run("scalar fields round-trip", func(t *testing.T) {
+		c := &AgentConfig{
+			SystemPrompt:     "sys",
+			MaxSteps:         7,
+			StreamingEnabled: true,
+			DisableCoreTools: true,
+		}
+		got := c.toInternal()
+		if got == nil {
+			t.Fatal("toInternal() = nil")
+		}
+		if got.SystemPrompt != "sys" {
+			t.Errorf("SystemPrompt = %q, want %q", got.SystemPrompt, "sys")
+		}
+		if got.MaxSteps != 7 {
+			t.Errorf("MaxSteps = %d, want 7", got.MaxSteps)
+		}
+		if !got.StreamingEnabled {
+			t.Error("StreamingEnabled = false, want true")
+		}
+		if !got.DisableCoreTools {
+			t.Error("DisableCoreTools = false, want true")
+		}
+	})
+
+	t.Run("tool slices propagate without conversion", func(t *testing.T) {
+		// Tool is a type alias for the underlying LLM-tool type, so the
+		// SDK []Tool and internal []fantasy.AgentTool slices share the
+		// same backing array after conversion.
+		tool := NewTool[struct{}]("noop", "noop", nil)
+		c := &AgentConfig{
+			CoreTools:  []Tool{tool},
+			ExtraTools: []Tool{tool, tool},
+		}
+		got := c.toInternal()
+		if len(got.CoreTools) != 1 {
+			t.Errorf("CoreTools len = %d, want 1", len(got.CoreTools))
+		}
+		if len(got.ExtraTools) != 2 {
+			t.Errorf("ExtraTools len = %d, want 2", len(got.ExtraTools))
+		}
+	})
+
+	t.Run("tool wrapper is invoked through internal config", func(t *testing.T) {
+		called := false
+		c := &AgentConfig{
+			ToolWrapper: func(in []Tool) []Tool {
+				called = true
+				return in
+			},
+		}
+		got := c.toInternal()
+		if got.ToolWrapper == nil {
+			t.Fatal("internal ToolWrapper is nil")
+		}
+		_ = got.ToolWrapper(nil)
+		if !called {
+			t.Error("SDK ToolWrapper was not invoked through the internal config")
+		}
+	})
+
+	t.Run("OnMCPServerLoaded propagates", func(t *testing.T) {
+		var captured string
+		wantErr := errors.New("boom")
+		c := &AgentConfig{
+			OnMCPServerLoaded: func(name string, _ int, _ error) {
+				captured = name
+			},
+		}
+		got := c.toInternal()
+		got.OnMCPServerLoaded("svr", 3, wantErr)
+		if captured != "svr" {
+			t.Errorf("OnMCPServerLoaded captured = %q, want %q", captured, "svr")
+		}
+	})
+
+	t.Run("DebugLogger propagates", func(t *testing.T) {
+		dl := &fakeDebugLogger{enabled: true}
+		c := &AgentConfig{DebugLogger: dl}
+		got := c.toInternal()
+		if got.DebugLogger == nil {
+			t.Fatal("internal DebugLogger is nil")
+		}
+		if !got.DebugLogger.IsDebugEnabled() {
+			t.Error("IsDebugEnabled = false, want true")
+		}
+		got.DebugLogger.LogDebug("hello")
+		if len(dl.messages) != 1 || dl.messages[0] != "hello" {
+			t.Errorf("messages = %v, want [hello]", dl.messages)
+		}
+	})
+
+	t.Run("MCPTaskConfig propagates with mode + progress", func(t *testing.T) {
+		c := &AgentConfig{
+			MCPTaskConfig: MCPTaskConfig{
+				PerServerMode: map[string]MCPTaskMode{
+					"build-svr": MCPTaskModeAlways,
+				},
+				DefaultTTL:      30 * time.Second,
+				PollInterval:    250 * time.Millisecond,
+				MaxPollInterval: 2 * time.Second,
+				Timeout:         5 * time.Minute,
+				Progress:        func(_ MCPTaskProgress) {},
+			},
+		}
+		got := c.toInternal()
+		if got.MCPTaskConfig.DefaultTTL != 30*time.Second {
+			t.Errorf("DefaultTTL = %v, want 30s", got.MCPTaskConfig.DefaultTTL)
+		}
+		if got.MCPTaskConfig.PollInterval != 250*time.Millisecond {
+			t.Errorf("PollInterval = %v, want 250ms", got.MCPTaskConfig.PollInterval)
+		}
+		if got.MCPTaskConfig.MaxPollInterval != 2*time.Second {
+			t.Errorf("MaxPollInterval = %v, want 2s", got.MCPTaskConfig.MaxPollInterval)
+		}
+		if got.MCPTaskConfig.Timeout != 5*time.Minute {
+			t.Errorf("Timeout = %v, want 5m", got.MCPTaskConfig.Timeout)
+		}
+		mode, ok := got.MCPTaskConfig.PerServerMode["build-svr"]
+		if !ok {
+			t.Fatal("PerServerMode missing 'build-svr'")
+		}
+		if string(mode) != string(MCPTaskModeAlways) {
+			t.Errorf("mode = %q, want %q", mode, MCPTaskModeAlways)
+		}
+		if got.MCPTaskConfig.Progress == nil {
+			t.Fatal("internal Progress handler is nil")
+		}
+	})
+
+	t.Run("auth and token store factories are wired", func(t *testing.T) {
+		auth := &fakeAuthHandler{}
+		tokenCalls := 0
+		var tokenServer string
+		factory := MCPTokenStoreFactory(func(server string) (MCPTokenStore, error) {
+			tokenCalls++
+			tokenServer = server
+			return nil, nil
+		})
+		c := &AgentConfig{
+			AuthHandler:       auth,
+			TokenStoreFactory: factory,
+		}
+		got := c.toInternal()
+		if got.AuthHandler == nil {
+			t.Fatal("internal AuthHandler is nil")
+		}
+		if got.TokenStoreFactory == nil {
+			t.Fatal("internal TokenStoreFactory is nil")
+		}
+		_, _ = got.TokenStoreFactory("https://example.test")
+		if tokenCalls != 1 {
+			t.Errorf("token factory call count = %d, want 1", tokenCalls)
+		}
+		if tokenServer != "https://example.test" {
+			t.Errorf("token factory server arg = %q", tokenServer)
+		}
+		if got.AuthHandler.RedirectURI() != "redirect" {
+			t.Errorf("RedirectURI = %q, want %q", got.AuthHandler.RedirectURI(), "redirect")
+		}
+	})
+
+	// Compile-time check that the internal type is what we expect.
+	//nolint:staticcheck // QF1011: explicit type asserts the conversion target.
+	var _ *agent.AgentConfig = (&AgentConfig{}).toInternal()
+}
+
+// fakeAuthHandler implements both kit.MCPAuthHandler and the structurally
+// identical tools.MCPAuthHandler used by the internal layer.
+type fakeAuthHandler struct{}
+
+func (f *fakeAuthHandler) RedirectURI() string { return "redirect" }
+func (f *fakeAuthHandler) HandleAuth(_ context.Context, _ string, _ string) (string, error) {
+	return "", nil
+}
+
+// fakeDebugLogger implements kit.DebugLogger for tests.
+type fakeDebugLogger struct {
+	enabled  bool
+	messages []string
+}
+
+func (f *fakeDebugLogger) LogDebug(m string)    { f.messages = append(f.messages, m) }
+func (f *fakeDebugLogger) IsDebugEnabled() bool { return f.enabled }

pkg/kit/context_files.go

@@ -0,0 +1,150 @@
+package kit
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// ---------------------------------------------------------------------------
+// Runtime context-file management (Issue #36)
+// ---------------------------------------------------------------------------
+//
+// Project context files (AGENTS.md and friends) are normally auto-discovered
+// during Kit.New() and injected into the system prompt. SDK consumers building
+// multi-tenant chatbots often need to swap context per user/session at runtime
+// without restarting the agent. The methods below provide that surface.
+//
+// Every mutation recomposes the system prompt and applies it to the underlying
+// agent so the next turn sees the updated project context.
+
+// AddContextFile registers a project context file (e.g. an AGENTS.md
+// equivalent) on this Kit instance. The file does not need to exist on
+// disk — Path is treated as an opaque identifier used both for de-duplication
+// and for the "Instructions from: <Path>" header injected into the system
+// prompt. If a context file with the same Path is already loaded the new
+// content replaces it.
+//
+// Returns an error when cf is nil or has an empty Path. AddContextFile is
+// safe to call from any goroutine.
+func (m *Kit) AddContextFile(cf *ContextFile) error {
+	if cf == nil {
+		return fmt.Errorf("AddContextFile: context file is nil")
+	}
+	if cf.Path == "" {
+		return fmt.Errorf("AddContextFile: context file path is required")
+	}
+
+	// Take a defensive copy so later mutations by the caller don't race with
+	// the agent reading the composed prompt.
+	stored := &ContextFile{
+		Path:    cf.Path,
+		Content: strings.TrimSpace(cf.Content),
+	}
+
+	m.runtimeMu.Lock()
+	replaced := false
+	for i, existing := range m.contextFiles {
+		if existing.Path == stored.Path {
+			m.contextFiles[i] = stored
+			replaced = true
+			break
+		}
+	}
+	if !replaced {
+		m.contextFiles = append(m.contextFiles, stored)
+	}
+	m.runtimeMu.Unlock()
+
+	m.applyComposedSystemPrompt()
+	return nil
+}
+
+// AddContextFileContent is a convenience wrapper around [Kit.AddContextFile]
+// that builds the ContextFile from a path and inline content string. Use this
+// when the context originates from a database, API response, or any other
+// non-filesystem source.
+func (m *Kit) AddContextFileContent(path, content string) (*ContextFile, error) {
+	cf := &ContextFile{Path: path, Content: content}
+	if err := m.AddContextFile(cf); err != nil {
+		return nil, err
+	}
+	return cf, nil
+}
+
+// LoadAndAddContextFile reads a file from disk and registers it as a project
+// context file via [Kit.AddContextFile]. The absolute path is stored on the
+// resulting ContextFile.
+func (m *Kit) LoadAndAddContextFile(path string) (*ContextFile, error) {
+	data, err := os.ReadFile(path)
+	if err != nil {
+		return nil, fmt.Errorf("LoadAndAddContextFile: %w", err)
+	}
+	abs, absErr := filepath.Abs(path)
+	if absErr != nil {
+		abs = path
+	}
+	cf := &ContextFile{
+		Path:    abs,
+		Content: strings.TrimSpace(string(data)),
+	}
+	if err := m.AddContextFile(cf); err != nil {
+		return nil, err
+	}
+	return cf, nil
+}
+
+// RemoveContextFile removes the context file with the given path and
+// recomposes the system prompt. Returns true when a matching file was found
+// and removed, false otherwise.
+func (m *Kit) RemoveContextFile(path string) bool {
+	m.runtimeMu.Lock()
+	found := false
+	for i, cf := range m.contextFiles {
+		if cf.Path == path {
+			m.contextFiles = append(m.contextFiles[:i], m.contextFiles[i+1:]...)
+			found = true
+			break
+		}
+	}
+	m.runtimeMu.Unlock()
+
+	if !found {
+		return false
+	}
+	m.applyComposedSystemPrompt()
+	return true
+}
+
+// SetContextFiles replaces the active context-file set with the provided
+// slice. Pass nil or an empty slice to clear all context. The system prompt
+// is recomposed and applied. ContextFiles with empty Paths are rejected and
+// no mutation is performed.
+func (m *Kit) SetContextFiles(files []*ContextFile) error {
+	// Validate first so a bad input doesn't partially mutate state.
+	for i, cf := range files {
+		if cf == nil {
+			return fmt.Errorf("SetContextFiles: context file at index %d is nil", i)
+		}
+		if cf.Path == "" {
+			return fmt.Errorf("SetContextFiles: context file at index %d has empty path", i)
+		}
+	}
+
+	// Defensive copies so caller-side mutation cannot race with composition.
+	copied := make([]*ContextFile, len(files))
+	for i, cf := range files {
+		copied[i] = &ContextFile{
+			Path:    cf.Path,
+			Content: strings.TrimSpace(cf.Content),
+		}
+	}
+
+	m.runtimeMu.Lock()
+	m.contextFiles = copied
+	m.runtimeMu.Unlock()
+
+	m.applyComposedSystemPrompt()
+	return nil
+}

pkg/kit/events.go

@@ -148,9 +148,9 @@ func parseToolArgs(toolArgs string) map[string]any {
 // ---------------------------------------------------------------------------
 
 // Finish reasons reported by the LLM provider on a completed turn. These
-// mirror fantasy.FinishReason string values so comparisons against
-// TurnEndEvent.StopReason / TurnResult.StopReason are stable across
-// providers.
+// mirror the underlying provider's finish reason string values so
+// comparisons against TurnEndEvent.StopReason / TurnResult.StopReason are
+// stable across providers.
 const (
 	// FinishReasonStop: the model produced a natural stop (e.g. stop sequence
 	// or end-of-turn signal).

pkg/kit/extension_api.go

@@ -8,55 +8,104 @@ import (
 	"github.com/mark3labs/kit/internal/session"
 )
 
+// ==== Extension Types ====
+//
+// Type aliases for internal extension types exposed through the public
+// ExtensionAPI interface. External SDK consumers can use these without
+// importing internal packages directly.
+
+// ExtensionContext holds the runtime context passed to extensions, including
+// callbacks for printing, sending messages, and accessing session state.
+type ExtensionContext = extensions.Context
+
+// ExtensionWidgetConfig describes a widget registered by an extension.
+type ExtensionWidgetConfig = extensions.WidgetConfig
+
+// ExtensionWidgetPlacement indicates where a widget should be rendered
+// (e.g. above or below the conversation).
+type ExtensionWidgetPlacement = extensions.WidgetPlacement
+
+// ExtensionHeaderFooterConfig describes a header or footer registered by an extension.
+type ExtensionHeaderFooterConfig = extensions.HeaderFooterConfig
+
+// ExtensionEditorConfig configures editor behaviour overrides set by extensions.
+type ExtensionEditorConfig = extensions.EditorConfig
+
+// ExtensionUIVisibility controls which UI elements are visible.
+type ExtensionUIVisibility = extensions.UIVisibility
+
+// ExtensionToolRenderConfig describes custom tool output rendering registered by an extension.
+type ExtensionToolRenderConfig = extensions.ToolRenderConfig
+
+// ExtensionMessageRendererConfig describes custom message rendering registered by an extension.
+type ExtensionMessageRendererConfig = extensions.MessageRendererConfig
+
+// ExtensionSessionMessage represents a single message in the session history
+// as exposed to extensions.
+type ExtensionSessionMessage = extensions.SessionMessage
+
+// ExtensionEntry represents a custom data entry stored by an extension
+// in the session tree.
+type ExtensionEntry = extensions.ExtensionEntry
+
+// ExtensionStatusBarEntry describes a status bar entry registered by an extension.
+type ExtensionStatusBarEntry = extensions.StatusBarEntry
+
+// ExtensionToolInfo describes a tool available to the agent, as seen by extensions.
+type ExtensionToolInfo = extensions.ToolInfo
+
+// ExtensionCommandDef describes a slash command registered by an extension.
+type ExtensionCommandDef = extensions.CommandDef
+
 // ExtensionAPI provides grouped access to all extension-related functionality.
 // This cleans up the main Kit API surface while keeping all extension capabilities available.
 type ExtensionAPI interface {
 	// Context management
-	SetContext(ctx extensions.Context)
-	GetContext() extensions.Context
+	SetContext(ctx ExtensionContext)
+	GetContext() ExtensionContext
 	UpdateContextModel(model string)
 
 	// Widgets
-	SetWidget(config extensions.WidgetConfig)
+	SetWidget(config ExtensionWidgetConfig)
 	RemoveWidget(id string)
-	GetWidgets(placement extensions.WidgetPlacement) []extensions.WidgetConfig
+	GetWidgets(placement ExtensionWidgetPlacement) []ExtensionWidgetConfig
 
 	// Header/Footer
-	SetHeader(config extensions.HeaderFooterConfig)
+	SetHeader(config ExtensionHeaderFooterConfig)
 	RemoveHeader()
-	GetHeader() *extensions.HeaderFooterConfig
-	SetFooter(config extensions.HeaderFooterConfig)
+	GetHeader() *ExtensionHeaderFooterConfig
+	SetFooter(config ExtensionHeaderFooterConfig)
 	RemoveFooter()
-	GetFooter() *extensions.HeaderFooterConfig
+	GetFooter() *ExtensionHeaderFooterConfig
 
 	// Editor
-	SetEditor(config extensions.EditorConfig)
+	SetEditor(config ExtensionEditorConfig)
 	ResetEditor()
-	GetEditor() *extensions.EditorConfig
+	GetEditor() *ExtensionEditorConfig
 
 	// UI Visibility
-	SetUIVisibility(v extensions.UIVisibility)
-	GetUIVisibility() *extensions.UIVisibility
+	SetUIVisibility(v ExtensionUIVisibility)
+	GetUIVisibility() *ExtensionUIVisibility
 
 	// Tool rendering
-	GetToolRenderer(toolName string) *extensions.ToolRenderConfig
-	GetMessageRenderer(name string) *extensions.MessageRendererConfig
+	GetToolRenderer(toolName string) *ExtensionToolRenderConfig
+	GetMessageRenderer(name string) *ExtensionMessageRendererConfig
 
 	// Session data
-	GetSessionMessages() []extensions.SessionMessage
+	GetSessionMessages() []ExtensionSessionMessage
 	AppendEntry(extType, data string) (string, error)
-	GetEntries(extType string) []extensions.ExtensionEntry
+	GetEntries(extType string) []ExtensionEntry
 
 	// Status bar
-	SetStatus(entry extensions.StatusBarEntry)
+	SetStatus(entry ExtensionStatusBarEntry)
 	RemoveStatus(key string)
-	GetStatusEntries() []extensions.StatusBarEntry
+	GetStatusEntries() []ExtensionStatusBarEntry
 
 	// Shortcuts
 	GetShortcuts() map[string]func()
 
 	// Tools
-	GetToolInfos() []extensions.ToolInfo
+	GetToolInfos() []ExtensionToolInfo
 	SetActiveTools(names []string)
 
 	// Options
@@ -71,11 +120,27 @@ type ExtensionAPI interface {
 	EmitBeforeSessionSwitch(switchReason string) (cancelled bool, reason string)
 
 	// Commands
-	Commands() []extensions.CommandDef
+	Commands() []ExtensionCommandDef
 
 	// Lifecycle
 	Reload() error
 	HasExtensions() bool
+
+	// Loaded returns metadata about the extensions currently loaded.
+	Loaded() []ExtensionInfo
+}
+
+// ExtensionInfo describes a single loaded extension for display purposes
+// (e.g. the startup banner or `kit extensions list`).
+type ExtensionInfo struct {
+	// Path is the absolute path of the extension's .go file.
+	Path string
+	// ToolCount is the number of tools registered by the extension.
+	ToolCount int
+	// CommandCount is the number of slash commands registered.
+	CommandCount int
+	// HandlerCount is the total number of event handlers registered.
+	HandlerCount int
 }
 
 // extensionAPI implements ExtensionAPI by wrapping a Kit instance.
@@ -456,3 +521,27 @@ func (e *extensionAPI) Reload() error {
 func (e *extensionAPI) HasExtensions() bool {
 	return e.kit.extRunner != nil
 }
+
+func (e *extensionAPI) Loaded() []ExtensionInfo {
+	if e.kit.extRunner == nil {
+		return nil
+	}
+	exts := e.kit.extRunner.Extensions()
+	if len(exts) == 0 {
+		return nil
+	}
+	infos := make([]ExtensionInfo, 0, len(exts))
+	for _, ex := range exts {
+		handlerCount := 0
+		for _, hs := range ex.Handlers {
+			handlerCount += len(hs)
+		}
+		infos = append(infos, ExtensionInfo{
+			Path:         ex.Path,
+			ToolCount:    len(ex.Tools),
+			CommandCount: len(ex.Commands),
+			HandlerCount: handlerCount,
+		})
+	}
+	return infos
+}

pkg/kit/extensions_bridge.go

@@ -54,83 +54,51 @@ func (m *Kit) bridgeExtensions(runner *extensions.Runner) {
 	// Subscribe to SDK events and forward to extension runner so extensions
 	// see lifecycle events from the SDK's runTurn()/generate() path.
 
-	if runner.HasHandlers(extensions.AgentStart) {
-		m.Subscribe(func(e Event) {
-			if ev, ok := e.(TurnStartEvent); ok {
-				_, _ = runner.Emit(extensions.AgentStartEvent{Prompt: ev.Prompt})
-			}
-		})
-	}
+	bridgeObserve(m, runner, extensions.AgentStart, func(ev TurnStartEvent) extensions.Event {
+		return extensions.AgentStartEvent{Prompt: ev.Prompt}
+	})
 
-	if runner.HasHandlers(extensions.MessageStart) {
-		m.Subscribe(func(e Event) {
-			if _, ok := e.(MessageStartEvent); ok {
-				_, _ = runner.Emit(extensions.MessageStartEvent{})
-			}
-		})
-	}
+	bridgeObserve(m, runner, extensions.MessageStart, func(_ MessageStartEvent) extensions.Event {
+		return extensions.MessageStartEvent{}
+	})
 
-	if runner.HasHandlers(extensions.MessageUpdate) {
-		m.Subscribe(func(e Event) {
-			if ev, ok := e.(MessageUpdateEvent); ok {
-				_, _ = runner.Emit(extensions.MessageUpdateEvent{Chunk: ev.Chunk})
-			}
-		})
-	}
+	bridgeObserve(m, runner, extensions.MessageUpdate, func(ev MessageUpdateEvent) extensions.Event {
+		return extensions.MessageUpdateEvent{Chunk: ev.Chunk}
+	})
 
-	if runner.HasHandlers(extensions.MessageEnd) {
-		m.Subscribe(func(e Event) {
-			if ev, ok := e.(MessageEndEvent); ok {
-				_, _ = runner.Emit(extensions.MessageEndEvent{Content: ev.Content})
-			}
-		})
-	}
+	bridgeObserve(m, runner, extensions.MessageEnd, func(ev MessageEndEvent) extensions.Event {
+		return extensions.MessageEndEvent{Content: ev.Content}
+	})
 
 	// Tool output streaming events (observation only).
-	if runner.HasHandlers(extensions.ToolOutput) {
-		m.Subscribe(func(e Event) {
-			if ev, ok := e.(ToolOutputEvent); ok {
-				_, _ = runner.Emit(extensions.ToolOutputEvent{
-					ToolCallID: ev.ToolCallID,
-					ToolName:   ev.ToolName,
-					Chunk:      ev.Chunk,
-					IsStderr:   ev.IsStderr,
-				})
-			}
-		})
-	}
+	bridgeObserve(m, runner, extensions.ToolOutput, func(ev ToolOutputEvent) extensions.Event {
+		return extensions.ToolOutputEvent{
+			ToolCallID: ev.ToolCallID,
+			ToolName:   ev.ToolName,
+			Chunk:      ev.Chunk,
+			IsStderr:   ev.IsStderr,
+		}
+	})
 
 	// Tool call input streaming events — fire as the LLM generates tool arguments.
-	if runner.HasHandlers(extensions.ToolCallInputStart) {
-		m.Subscribe(func(e Event) {
-			if ev, ok := e.(ToolCallStartEvent); ok {
-				_, _ = runner.Emit(extensions.ToolCallInputStartEvent{
-					ToolCallID: ev.ToolCallID,
-					ToolName:   ev.ToolName,
-					ToolKind:   ev.ToolKind,
-				})
-			}
-		})
-	}
-	if runner.HasHandlers(extensions.ToolCallInputDelta) {
-		m.Subscribe(func(e Event) {
-			if ev, ok := e.(ToolCallDeltaEvent); ok {
-				_, _ = runner.Emit(extensions.ToolCallInputDeltaEvent{
-					ToolCallID: ev.ToolCallID,
-					Delta:      ev.Delta,
-				})
-			}
-		})
-	}
-	if runner.HasHandlers(extensions.ToolCallInputEnd) {
-		m.Subscribe(func(e Event) {
-			if ev, ok := e.(ToolCallEndEvent); ok {
-				_, _ = runner.Emit(extensions.ToolCallInputEndEvent{
-					ToolCallID: ev.ToolCallID,
-				})
-			}
-		})
-	}
+	bridgeObserve(m, runner, extensions.ToolCallInputStart, func(ev ToolCallStartEvent) extensions.Event {
+		return extensions.ToolCallInputStartEvent{
+			ToolCallID: ev.ToolCallID,
+			ToolName:   ev.ToolName,
+			ToolKind:   ev.ToolKind,
+		}
+	})
+	bridgeObserve(m, runner, extensions.ToolCallInputDelta, func(ev ToolCallDeltaEvent) extensions.Event {
+		return extensions.ToolCallInputDeltaEvent{
+			ToolCallID: ev.ToolCallID,
+			Delta:      ev.Delta,
+		}
+	})
+	bridgeObserve(m, runner, extensions.ToolCallInputEnd, func(ev ToolCallEndEvent) extensions.Event {
+		return extensions.ToolCallInputEndEvent{
+			ToolCallID: ev.ToolCallID,
+		}
+	})
 
 	if runner.HasHandlers(extensions.AgentEnd) {
 		m.Subscribe(func(e Event) {
@@ -278,54 +246,13 @@ func (m *Kit) bridgeExtensions(runner *extensions.Runner) {
 	// Extension ContextPrepare → SDK ContextPrepare hook.
 	if runner.HasHandlers(extensions.ContextPrepare) {
 		m.OnContextPrepare(HookPriorityNormal, func(h ContextPrepareHook) *ContextPrepareResult {
-			// Convert LLM message slice to extension ContextMessage slice.
-			// Extract plain text from each message for the extension API.
-			extMsgs := make([]extensions.ContextMessage, len(h.Messages))
-			for i, msg := range h.Messages {
-				var sb strings.Builder
-				for _, part := range msg.Content {
-					if tp, ok := part.(LLMTextPart); ok {
-						sb.WriteString(tp.Text)
-					}
-				}
-				extMsgs[i] = extensions.ContextMessage{
-					Index:   i,
-					Role:    string(msg.Role),
-					Content: sb.String(),
-				}
-			}
-
+			extMsgs := llmToContextMessages(h.Messages)
 			result, _ := runner.Emit(extensions.ContextPrepareEvent{Messages: extMsgs})
 			r, ok := result.(extensions.ContextPrepareResult)
 			if !ok || r.Messages == nil {
 				return nil
 			}
-
-			// Rebuild LLM message slice from extension result.
-			rebuilt := make([]LLMMessage, 0, len(r.Messages))
-			for _, cm := range r.Messages {
-				if cm.Index >= 0 && cm.Index < len(h.Messages) {
-					// Reuse original message (preserves original role and content).
-					rebuilt = append(rebuilt, h.Messages[cm.Index])
-				} else {
-					// New message injected by extension — construct from role + text.
-					role := LLMRoleUser
-					switch cm.Role {
-					case "assistant":
-						role = LLMRoleAssistant
-					case "system":
-						role = LLMRoleSystem
-					case "tool":
-						role = LLMRoleTool
-					}
-					rebuilt = append(rebuilt, LLMMessage{
-						Role:    role,
-						Content: []LLMMessagePart{LLMTextPart{Text: cm.Content}},
-					})
-				}
-			}
-
-			return &ContextPrepareResult{Messages: rebuilt}
+			return &ContextPrepareResult{Messages: contextMessagesToLLM(r.Messages, h.Messages)}
 		})
 	}
 
@@ -359,99 +286,56 @@ func (m *Kit) bridgeExtensions(runner *extensions.Runner) {
 
 	// --- Step lifecycle observation events ---
 
-	if runner.HasHandlers(extensions.StepStart) {
-		m.Subscribe(func(e Event) {
-			if ev, ok := e.(StepStartEvent); ok {
-				_, _ = runner.Emit(extensions.StepStartEvent{StepNumber: ev.StepNumber})
-			}
-		})
-	}
+	bridgeObserve(m, runner, extensions.StepStart, func(ev StepStartEvent) extensions.Event {
+		return extensions.StepStartEvent{StepNumber: ev.StepNumber}
+	})
 
-	if runner.HasHandlers(extensions.StepFinish) {
-		m.Subscribe(func(e Event) {
-			if ev, ok := e.(StepFinishEvent); ok {
-				_, _ = runner.Emit(extensions.StepFinishEvent{
-					StepNumber:       ev.StepNumber,
-					HasToolCalls:     ev.HasToolCalls,
-					FinishReason:     ev.FinishReason,
-					InputTokens:      ev.Usage.InputTokens,
-					OutputTokens:     ev.Usage.OutputTokens,
-					CacheReadTokens:  ev.Usage.CacheReadTokens,
-					CacheWriteTokens: ev.Usage.CacheCreationTokens,
-				})
-			}
-		})
-	}
+	bridgeObserve(m, runner, extensions.StepFinish, func(ev StepFinishEvent) extensions.Event {
+		return extensions.StepFinishEvent{
+			StepNumber:       ev.StepNumber,
+			HasToolCalls:     ev.HasToolCalls,
+			FinishReason:     ev.FinishReason,
+			InputTokens:      ev.Usage.InputTokens,
+			OutputTokens:     ev.Usage.OutputTokens,
+			CacheReadTokens:  ev.Usage.CacheReadTokens,
+			CacheWriteTokens: ev.Usage.CacheCreationTokens,
+		}
+	})
 
-	if runner.HasHandlers(extensions.ReasoningStart) {
-		m.Subscribe(func(e Event) {
-			if ev, ok := e.(ReasoningStartEvent); ok {
-				_, _ = runner.Emit(extensions.ReasoningStartEvent{ID: ev.ID})
-			}
-		})
-	}
+	bridgeObserve(m, runner, extensions.ReasoningStart, func(ev ReasoningStartEvent) extensions.Event {
+		return extensions.ReasoningStartEvent{ID: ev.ID}
+	})
 
-	if runner.HasHandlers(extensions.Warnings) {
-		m.Subscribe(func(e Event) {
-			if ev, ok := e.(WarningsEvent); ok {
-				_, _ = runner.Emit(extensions.WarningsEvent{Warnings: ev.Warnings})
-			}
-		})
-	}
+	bridgeObserve(m, runner, extensions.Warnings, func(ev WarningsEvent) extensions.Event {
+		return extensions.WarningsEvent{Warnings: ev.Warnings}
+	})
 
-	if runner.HasHandlers(extensions.Source) {
-		m.Subscribe(func(e Event) {
-			if ev, ok := e.(SourceEvent); ok {
-				_, _ = runner.Emit(extensions.SourceEvent{
-					SourceType: ev.SourceType,
-					ID:         ev.ID,
-					URL:        ev.URL,
-					Title:      ev.Title,
-				})
-			}
-		})
-	}
+	bridgeObserve(m, runner, extensions.Source, func(ev SourceEvent) extensions.Event {
+		return extensions.SourceEvent{
+			SourceType: ev.SourceType,
+			ID:         ev.ID,
+			URL:        ev.URL,
+			Title:      ev.Title,
+		}
+	})
 
-	if runner.HasHandlers(extensions.Error) {
-		m.Subscribe(func(e Event) {
-			if ev, ok := e.(ErrorEvent); ok {
-				_, _ = runner.Emit(extensions.ErrorEvent{Error: ev.Error.Error()})
-			}
-		})
-	}
+	bridgeObserve(m, runner, extensions.Error, func(ev ErrorEvent) extensions.Event {
+		return extensions.ErrorEvent{Error: ev.Error.Error()}
+	})
 
-	if runner.HasHandlers(extensions.Retry) {
-		m.Subscribe(func(e Event) {
-			if ev, ok := e.(RetryEvent); ok {
-				_, _ = runner.Emit(extensions.RetryEvent{
-					Attempt: ev.Attempt,
-					Error:   ev.Error.Error(),
-				})
-			}
-		})
-	}
+	bridgeObserve(m, runner, extensions.Retry, func(ev RetryEvent) extensions.Event {
+		return extensions.RetryEvent{
+			Attempt: ev.Attempt,
+			Error:   ev.Error.Error(),
+		}
+	})
 
 	// --- PrepareStep hook ---
 	// Extension PrepareStep → SDK PrepareStep hook.
 	// Same pattern as ContextPrepare: convert LLMMessage ↔ ContextMessage.
 	if runner.HasHandlers(extensions.PrepareStep) {
 		m.OnPrepareStep(HookPriorityNormal, func(h PrepareStepHook) *PrepareStepResult {
-			// Convert LLM message slice to extension ContextMessage slice.
-			extMsgs := make([]extensions.ContextMessage, len(h.Messages))
-			for i, msg := range h.Messages {
-				var sb strings.Builder
-				for _, part := range msg.Content {
-					if tp, ok := part.(LLMTextPart); ok {
-						sb.WriteString(tp.Text)
-					}
-				}
-				extMsgs[i] = extensions.ContextMessage{
-					Index:   i,
-					Role:    string(msg.Role),
-					Content: sb.String(),
-				}
-			}
-
+			extMsgs := llmToContextMessages(h.Messages)
 			result, _ := runner.Emit(extensions.PrepareStepEvent{
 				StepNumber: h.StepNumber,
 				Messages:   extMsgs,
@@ -460,30 +344,71 @@ func (m *Kit) bridgeExtensions(runner *extensions.Runner) {
 			if !ok || r.Messages == nil {
 				return nil
 			}
-
-			// Rebuild LLM message slice from extension result.
-			rebuilt := make([]LLMMessage, 0, len(r.Messages))
-			for _, cm := range r.Messages {
-				if cm.Index >= 0 && cm.Index < len(h.Messages) {
-					rebuilt = append(rebuilt, h.Messages[cm.Index])
-				} else {
-					role := LLMRoleUser
-					switch cm.Role {
-					case "assistant":
-						role = LLMRoleAssistant
-					case "system":
-						role = LLMRoleSystem
-					case "tool":
-						role = LLMRoleTool
-					}
-					rebuilt = append(rebuilt, LLMMessage{
-						Role:    role,
-						Content: []LLMMessagePart{LLMTextPart{Text: cm.Content}},
-					})
-				}
-			}
-
-			return &PrepareStepResult{Messages: rebuilt}
+			return &PrepareStepResult{Messages: contextMessagesToLLM(r.Messages, h.Messages)}
 		})
 	}
 }
+
+// bridgeObserve subscribes to SDK events of type In and forwards them to the
+// extension runner as the event returned by conv. The subscription is only
+// registered when the runner has handlers for the given event kind.
+func bridgeObserve[In Event](m *Kit, runner *extensions.Runner, kind extensions.EventType, conv func(In) extensions.Event) {
+	if !runner.HasHandlers(kind) {
+		return
+	}
+	m.Subscribe(func(e Event) {
+		if ev, ok := e.(In); ok {
+			_, _ = runner.Emit(conv(ev))
+		}
+	})
+}
+
+// llmToContextMessages converts a slice of LLM messages to extension
+// ContextMessage values, extracting plain text from each message.
+func llmToContextMessages(msgs []LLMMessage) []extensions.ContextMessage {
+	extMsgs := make([]extensions.ContextMessage, len(msgs))
+	for i, msg := range msgs {
+		var sb strings.Builder
+		for _, part := range msg.Content {
+			if tp, ok := part.(LLMTextPart); ok {
+				sb.WriteString(tp.Text)
+			}
+		}
+		extMsgs[i] = extensions.ContextMessage{
+			Index:   i,
+			Role:    string(msg.Role),
+			Content: sb.String(),
+		}
+	}
+	return extMsgs
+}
+
+// contextMessagesToLLM rebuilds an LLM message slice from extension
+// ContextMessages. Messages with a valid index reuse the original from
+// originals; new messages injected by extensions are constructed from
+// role + text.
+func contextMessagesToLLM(cms []extensions.ContextMessage, originals []LLMMessage) []LLMMessage {
+	rebuilt := make([]LLMMessage, 0, len(cms))
+	for _, cm := range cms {
+		if cm.Index >= 0 && cm.Index < len(originals) {
+			// Reuse original message (preserves original role and content).
+			rebuilt = append(rebuilt, originals[cm.Index])
+		} else {
+			// New message injected by extension — construct from role + text.
+			role := LLMRoleUser
+			switch cm.Role {
+			case "assistant":
+				role = LLMRoleAssistant
+			case "system":
+				role = LLMRoleSystem
+			case "tool":
+				role = LLMRoleTool
+			}
+			rebuilt = append(rebuilt, LLMMessage{
+				Role:    role,
+				Content: []LLMMessagePart{LLMTextPart{Text: cm.Content}},
+			})
+		}
+	}
+	return rebuilt
+}

pkg/kit/kit.go

@@ -58,6 +58,14 @@ type Kit struct {
 	// When false, per-model system prompts from modelSettings/customModels
 	// can replace the default prompt on model switch.
 	hasCustomSystemPrompt bool
+	// systemPromptSource holds the raw configured value (file path or text)
+	// when hasCustomSystemPrompt is true; empty when the built-in default is in use.
+	systemPromptSource string
+	// basePrompt holds the resolved base system prompt text (post file-load,
+	// pre runtime-context composition) captured during New. Used by
+	// RefreshSystemPrompt to recompose after skills/context-file mutations.
+	// Protected by runtimeMu.
+	basePrompt string
 
 	// Hook registries — interception layer (see hooks.go).
 	beforeToolCall  *hookRegistry[BeforeToolCallHook, BeforeToolCallResult]
@@ -87,6 +95,12 @@ type Kit struct {
 		mu     sync.RWMutex
 	}
 
+	// runtimeMu protects contextFiles and skills against concurrent runtime
+	// mutations via AddSkill / RemoveSkill / AddContextFile etc. The fields
+	// are read by composeSystemPrompt and several other accessors, so all
+	// reads and writes after Kit construction must take this lock.
+	runtimeMu sync.RWMutex
+
 	// steerCh is a buffered channel used to inject steering messages into
 	// the running agent turn via the LLM library's PrepareStep. Created fresh for
 	// each generate() call and set to nil when idle. Protected by steerMu.
@@ -632,21 +646,43 @@ func (m *Kit) SetModel(ctx context.Context, modelString string) error {
 	return nil
 }
 
+// HasCustomSystemPrompt reports whether the user explicitly configured a system
+// prompt via --system-prompt, a config file entry, or SDK Options.SystemPrompt.
+// When false, the built-in default (or a per-model override) is in use and can
+// be replaced transparently on model switch.
+func (m *Kit) HasCustomSystemPrompt() bool {
+	return m.hasCustomSystemPrompt
+}
+
+// GetSystemPromptSource returns the raw configured value — a file path or
+// inline text — when HasCustomSystemPrompt is true; returns an empty string
+// when the built-in default prompt is active.
+func (m *Kit) GetSystemPromptSource() string {
+	return m.systemPromptSource
+}
+
 // composeSystemPrompt takes a base system prompt and composes it with the
 // current runtime context: AGENTS.md content, skills metadata, and date/cwd.
 // This mirrors the composition done during Kit.New() initialization.
+// It acquires a read lock on runtimeMu while snapshotting contextFiles and
+// skills, so callers must not hold the write lock.
 func (m *Kit) composeSystemPrompt(basePrompt string) string {
 	cwd, _ := os.Getwd()
 	pb := skills.NewPromptBuilder(basePrompt)
 
+	m.runtimeMu.RLock()
+	contextFiles := append([]*ContextFile(nil), m.contextFiles...)
+	loadedSkills := append([]*skills.Skill(nil), m.skills...)
+	m.runtimeMu.RUnlock()
+
 	// Inject AGENTS.md content as project context.
-	for _, cf := range m.contextFiles {
+	for _, cf := range contextFiles {
 		pb.WithSection("", fmt.Sprintf("Instructions from: %s\n\n%s", cf.Path, cf.Content))
 	}
 
 	// Inject skills metadata.
-	if len(m.skills) > 0 {
-		pb.WithSkills(m.skills)
+	if len(loadedSkills) > 0 {
+		pb.WithSkills(loadedSkills)
 	}
 
 	// Append current date/time and working directory.
@@ -1035,6 +1071,41 @@ type Options struct {
 	// real-time progress in the TUI.
 	OnMCPServerLoaded func(serverName string, toolCount int, err error)
 
+	// MCPTaskMode overrides the per-server [MCPTaskMode] for task-augmented
+	// tools/call execution. Keys are MCP server names. Servers not present
+	// in the map fall back to the TasksMode field of MCPServerConfig (or
+	// MCPTaskModeAuto when that is empty). See the MCP Tasks spec for the
+	// underlying semantics:
+	// https://modelcontextprotocol.io/specification/2025-11-25/basic/utilities/tasks
+	MCPTaskMode map[string]MCPTaskMode
+
+	// MCPTaskTimeout is the maximum wall-clock duration to wait for a
+	// task-augmented tool call to reach a terminal state. Independent of
+	// any per-call context deadline; whichever fires first wins. Zero
+	// means use the default (15 minutes).
+	MCPTaskTimeout time.Duration
+
+	// MCPTaskTTL is the TTL hint sent in TaskParams for every
+	// task-augmented tools/call. Zero omits the TTL and lets the server
+	// pick its own retention policy.
+	MCPTaskTTL time.Duration
+
+	// MCPTaskPollInterval is the fallback interval between tasks/get
+	// requests when the server does not suggest one. Zero means use the
+	// default (1 second).
+	MCPTaskPollInterval time.Duration
+
+	// MCPTaskMaxPollInterval caps the polling interval (a server-supplied
+	// pollInterval can otherwise grow without bound). Zero means use the
+	// default (5 seconds).
+	MCPTaskMaxPollInterval time.Duration
+
+	// MCPTaskProgress, if non-nil, is invoked once when a task is accepted
+	// and on every status transition observed by the polling loop. The
+	// final invocation always carries a terminal status. Implementations
+	// must not block; long work should run on a goroutine.
+	MCPTaskProgress MCPTaskProgressHandler
+
 	// CLI is optional CLI-specific configuration. SDK users leave this nil.
 	CLI *CLIOptions
 
@@ -1144,6 +1215,8 @@ func New(ctx context.Context, opts *Options) (*Kit, error) {
 		maxSteps              int
 		streaming             bool
 		hasCustomSystemPrompt bool
+		systemPromptSource    string
+		capturedBasePrompt    string
 	)
 
 	if err := func() error {
@@ -1250,13 +1323,27 @@ func New(ctx context.Context, opts *Options) (*Kit, error) {
 		// explicitly set system-prompt, use the per-model prompt as the
 		// base instead of the global default.
 		{
-			basePrompt := viper.GetString("system-prompt")
+			rawPromptInput := viper.GetString("system-prompt")
+
+			// Resolve a file path to its content so PromptBuilder receives the
+			// actual prompt text rather than a literal path string. Without this,
+			// when system-prompt is set to a file path in the config file or via
+			// --system-prompt, the path itself becomes the effective system prompt
+			// sent to the model (LoadSystemPrompt only ran later, after viper had
+			// been overwritten with the augmented base text).
+			basePrompt, _ := config.LoadSystemPrompt(rawPromptInput)
+			if basePrompt == "" {
+				basePrompt = rawPromptInput
+			}
 
 			// Track whether the user explicitly configured a custom system
 			// prompt. When they haven't (basePrompt is the built-in default
 			// or empty), per-model system prompts can replace it on switch.
 			userSetSystemPrompt := basePrompt != "" && basePrompt != defaultSystemPrompt
 			hasCustomSystemPrompt = userSetSystemPrompt
+			if hasCustomSystemPrompt {
+				systemPromptSource = rawPromptInput
+			}
 
 			// Check for per-model system prompt override when no explicit
 			// global system-prompt was configured by the user.
@@ -1281,6 +1368,10 @@ func New(ctx context.Context, opts *Options) (*Kit, error) {
 
 			pb := skills.NewPromptBuilder(basePrompt)
 
+			// Capture the resolved base prompt so RefreshSystemPrompt can
+			// recompose later after runtime skill/context-file mutations.
+			capturedBasePrompt = basePrompt
+
 			// Inject AGENTS.md content as project context.
 			for _, cf := range contextFiles {
 				pb.WithSection("", fmt.Sprintf("Instructions from: %s\n\n%s", cf.Path, cf.Content))
@@ -1387,6 +1478,14 @@ func New(ctx context.Context, opts *Options) (*Kit, error) {
 		MaxSteps:          maxSteps,
 		StreamingEnabled:  streaming,
 		OnMCPServerLoaded: opts.OnMCPServerLoaded,
+		MCPTaskConfig: mcpTaskOptions{
+			perServer:       opts.MCPTaskMode,
+			defaultTTL:      opts.MCPTaskTTL,
+			pollInterval:    opts.MCPTaskPollInterval,
+			maxPollInterval: opts.MCPTaskMaxPollInterval,
+			timeout:         opts.MCPTaskTimeout,
+			progress:        opts.MCPTaskProgress,
+		}.toToolsConfig(),
 	}
 
 	// Set up OAuth handler for remote MCP servers. The SDK does not create
@@ -1413,7 +1512,7 @@ func New(ctx context.Context, opts *Options) (*Kit, error) {
 
 	if opts.CLI != nil {
 		setupOpts.ShowSpinner = opts.CLI.ShowSpinner
-		setupOpts.SpinnerFunc = opts.CLI.SpinnerFunc
+		setupOpts.SpinnerFunc = agent.SpinnerFunc(opts.CLI.SpinnerFunc)
 		setupOpts.UseBufferedLogger = opts.CLI.UseBufferedLogger
 		if opts.CLI.ProgressReaderFunc != nil {
 			providerConfig.ProgressReaderFunc = opts.CLI.ProgressReaderFunc
@@ -1457,6 +1556,8 @@ func New(ctx context.Context, opts *Options) (*Kit, error) {
 		opts:                  opts,
 		mcpConfig:             mcpConfig,
 		hasCustomSystemPrompt: hasCustomSystemPrompt,
+		systemPromptSource:    systemPromptSource,
+		basePrompt:            capturedBasePrompt,
 		beforeToolCall:        beforeToolCall,
 		afterToolResult:       afterToolResult,
 		beforeTurn:            beforeTurn,
@@ -1483,15 +1584,32 @@ func New(ctx context.Context, opts *Options) (*Kit, error) {
 	return k, nil
 }
 
-// GetContextFiles returns the context files (e.g. AGENTS.md) loaded during
-// initialisation. Returns nil if no context files were found.
+// GetContextFiles returns the context files (e.g. AGENTS.md) currently active
+// on this Kit instance. The returned slice is a snapshot — mutating it does
+// not affect Kit state. Returns nil when no context files are loaded.
 func (m *Kit) GetContextFiles() []*ContextFile {
-	return m.contextFiles
+	m.runtimeMu.RLock()
+	defer m.runtimeMu.RUnlock()
+	if len(m.contextFiles) == 0 {
+		return nil
+	}
+	out := make([]*ContextFile, len(m.contextFiles))
+	copy(out, m.contextFiles)
+	return out
 }
 
-// GetSkills returns the skills loaded during initialisation.
+// GetSkills returns the skills currently active on this Kit instance. The
+// returned slice is a snapshot — mutating it does not affect Kit state.
+// Returns nil when no skills are loaded.
 func (m *Kit) GetSkills() []*Skill {
-	return m.skills
+	m.runtimeMu.RLock()
+	defer m.runtimeMu.RUnlock()
+	if len(m.skills) == 0 {
+		return nil
+	}
+	out := make([]*Skill, len(m.skills))
+	copy(out, m.skills)
+	return out
 }
 
 // ---------------------------------------------------------------------------
@@ -1536,12 +1654,14 @@ func (m *Kit) expandSkillCommand(prompt string) string {
 
 	// Find the skill by name.
 	var skillPath string
+	m.runtimeMu.RLock()
 	for _, s := range m.skills {
 		if s.Name == name {
 			skillPath = s.Path
 			break
 		}
 	}
+	m.runtimeMu.RUnlock()
 	if skillPath == "" {
 		return prompt
 	}
@@ -1799,6 +1919,13 @@ func (m *Kit) Subagent(ctx context.Context, cfg SubagentConfig) (*SubagentResult
 		Streaming:    true,
 		MCPConfig:    m.mcpConfig,
 	}
+	// Propagate the parent's MCP task configuration so a child subagent
+	// invoking long-running MCP tools observes the same per-server modes,
+	// timeouts, and progress callback as the parent. Without this, child
+	// agents would silently fall back to MCPTaskModeAuto with default
+	// polling and no progress feedback even when the parent had configured
+	// custom values.
+	inheritMCPTaskOptions(childOpts, m.opts)
 	child, err := New(ctx, childOpts)
 	if err != nil {
 		return &SubagentResult{Elapsed: time.Since(start)}, fmt.Errorf("failed to create subagent: %w", err)
@@ -2042,7 +2169,7 @@ func (m *Kit) generate(ctx context.Context, messages []fantasy.Message) (*agent.
 			})
 		},
 
-		// New callbacks for previously unwired Fantasy lifecycle events.
+		// New callbacks for previously unwired agent lifecycle events.
 		OnStepStart: func(stepNumber int) {
 			m.events.emit(StepStartEvent{StepNumber: stepNumber})
 		},

pkg/kit/kit_test.go

@@ -3,6 +3,7 @@ package kit_test
 import (
 	"context"
 	"os"
+	"strings"
 	"testing"
 
 	"github.com/spf13/viper"
@@ -306,3 +307,92 @@ func TestSessionManagement(t *testing.T) {
 // resetViper wipes viper's global state so a test case doesn't leak
 // viper.Set() calls into the next one. Used via defer in subtests.
 func resetViper() { viper.Reset() }
+
+// TestNewSystemPromptFilePath is a regression test for issue #25.
+//
+// When Options.SystemPrompt (or the --system-prompt flag / config entry) is a
+// file path, Kit must resolve the path to its file contents *before* the
+// PromptBuilder composes the runtime context. Previously the path string
+// itself was used verbatim as the base prompt, so the LLM received the path —
+// not the prompt — as its system message.
+func TestNewSystemPromptFilePath(t *testing.T) {
+	if os.Getenv("ANTHROPIC_API_KEY") == "" {
+		t.Skip("Skipping test: ANTHROPIC_API_KEY not set")
+	}
+	defer resetViper()
+
+	const promptContent = "You are a strict regression-test persona. Marker: KIT-25-OK"
+
+	tmpFile, err := os.CreateTemp(t.TempDir(), "kit-system-prompt-*.md")
+	if err != nil {
+		t.Fatalf("failed to create temp prompt file: %v", err)
+	}
+	if _, err := tmpFile.WriteString(promptContent); err != nil {
+		t.Fatalf("failed to write temp prompt file: %v", err)
+	}
+	if err := tmpFile.Close(); err != nil {
+		t.Fatalf("failed to close temp prompt file: %v", err)
+	}
+
+	ctx := context.Background()
+	host, err := kit.New(ctx, &kit.Options{
+		Model:        "anthropic/claude-sonnet-4-5-20250929",
+		SystemPrompt: tmpFile.Name(),
+		Quiet:        true,
+		NoSession:    true,
+	})
+	if err != nil {
+		t.Fatalf("Failed to create Kit with system-prompt file: %v", err)
+	}
+	defer func() { _ = host.Close() }()
+
+	if !host.HasCustomSystemPrompt() {
+		t.Error("HasCustomSystemPrompt() = false; want true when --system-prompt is set")
+	}
+	if got, want := host.GetSystemPromptSource(), tmpFile.Name(); got != want {
+		t.Errorf("GetSystemPromptSource() = %q; want %q", got, want)
+	}
+
+	// The composed system prompt is written back to viper after PromptBuilder
+	// runs. It must contain the file's contents, not the file path.
+	composed := viper.GetString("system-prompt")
+	if !strings.Contains(composed, promptContent) {
+		t.Errorf("composed system-prompt does not contain file contents\n  composed = %q\n  want substring = %q", composed, promptContent)
+	}
+	if strings.TrimSpace(composed) == tmpFile.Name() {
+		t.Errorf("composed system-prompt is the file path verbatim (%q); LoadSystemPrompt was not applied before PromptBuilder", composed)
+	}
+}
+
+// TestNewSystemPromptInline confirms that inline system-prompt strings still
+// flow through unchanged after the file-path resolution change.
+func TestNewSystemPromptInline(t *testing.T) {
+	if os.Getenv("ANTHROPIC_API_KEY") == "" {
+		t.Skip("Skipping test: ANTHROPIC_API_KEY not set")
+	}
+	defer resetViper()
+
+	const inline = "You are a concise inline-prompt persona."
+
+	ctx := context.Background()
+	host, err := kit.New(ctx, &kit.Options{
+		Model:        "anthropic/claude-sonnet-4-5-20250929",
+		SystemPrompt: inline,
+		Quiet:        true,
+		NoSession:    true,
+	})
+	if err != nil {
+		t.Fatalf("Failed to create Kit with inline system-prompt: %v", err)
+	}
+	defer func() { _ = host.Close() }()
+
+	if !host.HasCustomSystemPrompt() {
+		t.Error("HasCustomSystemPrompt() = false; want true for inline prompt")
+	}
+	if got := host.GetSystemPromptSource(); got != inline {
+		t.Errorf("GetSystemPromptSource() = %q; want %q", got, inline)
+	}
+	if composed := viper.GetString("system-prompt"); !strings.Contains(composed, inline) {
+		t.Errorf("composed system-prompt missing inline content; got %q", composed)
+	}
+}

pkg/kit/mcp_tasks.go

@@ -0,0 +1,300 @@
+package kit
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/mark3labs/kit/internal/tools"
+	"github.com/mark3labs/mcp-go/mcp"
+)
+
+// MCPTaskStatus represents the lifecycle state of a task-augmented MCP
+// tool call. See https://modelcontextprotocol.io/specification/2025-11-25/basic/utilities/tasks
+// for the underlying spec.
+type MCPTaskStatus string
+
+const (
+	// MCPTaskStatusWorking indicates the task is currently being processed.
+	MCPTaskStatusWorking MCPTaskStatus = MCPTaskStatus(mcp.TaskStatusWorking)
+	// MCPTaskStatusInputRequired indicates the server is waiting for client
+	// input before it can proceed (rare; typically surfaced via elicitation).
+	MCPTaskStatusInputRequired MCPTaskStatus = MCPTaskStatus(mcp.TaskStatusInputRequired)
+	// MCPTaskStatusCompleted indicates the task finished successfully.
+	MCPTaskStatusCompleted MCPTaskStatus = MCPTaskStatus(mcp.TaskStatusCompleted)
+	// MCPTaskStatusFailed indicates the task ended in error.
+	MCPTaskStatusFailed MCPTaskStatus = MCPTaskStatus(mcp.TaskStatusFailed)
+	// MCPTaskStatusCancelled indicates the task was cancelled before completion.
+	MCPTaskStatusCancelled MCPTaskStatus = MCPTaskStatus(mcp.TaskStatusCancelled)
+)
+
+// IsTerminal reports whether the status represents a final state — that is,
+// the task will not change again. Terminal states are completed, failed,
+// and cancelled.
+func (s MCPTaskStatus) IsTerminal() bool {
+	return mcp.TaskStatus(s).IsTerminal()
+}
+
+// MCPTaskMode controls when Kit augments tools/call requests with MCP task
+// metadata for a specific server.
+type MCPTaskMode string
+
+const (
+	// MCPTaskModeAuto augments tools/call with task metadata only when the
+	// server advertises tasks/toolCalls capability during initialize.
+	// This is the default and is safe to leave unconfigured for any
+	// existing MCP server.
+	MCPTaskModeAuto MCPTaskMode = MCPTaskMode(tools.MCPTaskModeAuto)
+	// MCPTaskModeNever forces every tools/call to be issued synchronously
+	// (no Task field), regardless of server capability.
+	MCPTaskModeNever MCPTaskMode = MCPTaskMode(tools.MCPTaskModeNever)
+	// MCPTaskModeAlways always opts into task augmentation, even when the
+	// server didn't advertise the capability. The server may still respond
+	// synchronously; this just expresses client intent unconditionally.
+	MCPTaskModeAlways MCPTaskMode = MCPTaskMode(tools.MCPTaskModeAlways)
+)
+
+// MCPTask is the SDK-level view of an MCP Task. Timestamps are best-effort
+// parsed from the server's ISO-8601 strings; they may be the zero time when
+// the server omitted them or used a non-RFC3339 format.
+type MCPTask struct {
+	// Server is the configured MCP server name this task lives on.
+	Server string
+	// TaskID is the server-assigned identifier for the task.
+	TaskID string
+	// Status is the current task lifecycle state.
+	Status MCPTaskStatus
+	// StatusMessage is an optional human-readable description provided by
+	// the server.
+	StatusMessage string
+	// CreatedAt is when the task was created on the server.
+	CreatedAt time.Time
+	// UpdatedAt is when the task was last updated on the server.
+	UpdatedAt time.Time
+	// TTL is how long the server intends to retain this task after creation.
+	// Zero means the server did not advertise a TTL.
+	TTL time.Duration
+	// PollInterval is the suggested time between status checks. Zero means
+	// the client should use its own default.
+	PollInterval time.Duration
+}
+
+// MCPTaskProgress is a single status update emitted while Kit is waiting
+// on a task-augmented tool call.
+type MCPTaskProgress struct {
+	// Server is the configured MCP server name.
+	Server string
+	// TaskID is the server-assigned identifier for the in-flight task.
+	TaskID string
+	// Status is the most recent task status observed.
+	Status MCPTaskStatus
+	// Message is the optional human-readable status message from the server.
+	Message string
+}
+
+// MCPTaskProgressHandler is called once when a task is accepted and again
+// on every observed status transition. The final invocation always carries
+// a terminal status. Implementations must not block; long work should be
+// dispatched on a goroutine.
+type MCPTaskProgressHandler func(MCPTaskProgress)
+
+// MCPTaskConfig configures task-aware MCP tools/call execution. All fields
+// are optional; the zero value disables progress callbacks and applies
+// sensible polling defaults inside the engine.
+//
+// For most consumers, the flat [Options] fields (`MCPTaskMode`,
+// `MCPTaskTTL`, `MCPTaskPollInterval`, `MCPTaskMaxPollInterval`,
+// `MCPTaskTimeout`, `MCPTaskProgress`) are the preferred entry point.
+// MCPTaskConfig is exposed for the low-level [AgentConfig] path.
+type MCPTaskConfig struct {
+	// PerServerMode overrides the per-server task mode resolved from
+	// [MCPServerConfig]. Keys are server names. Missing entries fall back
+	// to the configured value.
+	PerServerMode map[string]MCPTaskMode
+
+	// DefaultTTL is the TTL hint sent in TaskParams when augmenting a
+	// tools/call. Zero means omit the TTL — let the server pick its own.
+	DefaultTTL time.Duration
+
+	// PollInterval is the fallback interval between tasks/get requests
+	// when the server does not suggest one. Zero defaults to 1 second.
+	PollInterval time.Duration
+
+	// MaxPollInterval caps the polling interval. Zero defaults to 5 seconds.
+	MaxPollInterval time.Duration
+
+	// Timeout is the maximum wall-clock duration to wait for a task to
+	// reach a terminal state. Zero defaults to 15 minutes. Independent
+	// of the per-call context deadline; whichever fires first wins.
+	Timeout time.Duration
+
+	// Progress, if non-nil, receives every status transition observed by
+	// the polling loop.
+	Progress MCPTaskProgressHandler
+}
+
+// toToolsConfig converts the SDK-level [MCPTaskConfig] to the internal
+// tools-package representation. Keeps the dependency arrow internal-only.
+func (c MCPTaskConfig) toToolsConfig() tools.MCPTaskConfig {
+	cfg := tools.MCPTaskConfig{
+		DefaultTTL:      c.DefaultTTL,
+		PollInterval:    c.PollInterval,
+		MaxPollInterval: c.MaxPollInterval,
+		Timeout:         c.Timeout,
+	}
+	if len(c.PerServerMode) > 0 {
+		cfg.PerServerMode = make(map[string]tools.MCPTaskMode, len(c.PerServerMode))
+		for k, v := range c.PerServerMode {
+			cfg.PerServerMode[k] = tools.MCPTaskMode(v)
+		}
+	}
+	if c.Progress != nil {
+		h := c.Progress
+		cfg.Progress = func(p tools.MCPTaskProgress) {
+			h(MCPTaskProgress{
+				Server:  p.Server,
+				TaskID:  p.TaskID,
+				Status:  MCPTaskStatus(p.Status),
+				Message: p.Message,
+			})
+		}
+	}
+	return cfg
+}
+
+// mcpTaskOptions carries SDK consumer configuration into the agent setup.
+// Stored on Options as a single value so the public surface stays compact;
+// individual fields are exposed via WithMCP* builder functions.
+type mcpTaskOptions struct {
+	perServer       map[string]MCPTaskMode
+	defaultTTL      time.Duration
+	pollInterval    time.Duration
+	maxPollInterval time.Duration
+	timeout         time.Duration
+	progress        MCPTaskProgressHandler
+}
+
+// toToolsConfig converts the SDK-level config to the internal tools-package
+// representation. Keeps the dependency arrow internal-only.
+func (o mcpTaskOptions) toToolsConfig() tools.MCPTaskConfig {
+	cfg := tools.MCPTaskConfig{
+		DefaultTTL:      o.defaultTTL,
+		PollInterval:    o.pollInterval,
+		MaxPollInterval: o.maxPollInterval,
+		Timeout:         o.timeout,
+	}
+	if len(o.perServer) > 0 {
+		cfg.PerServerMode = make(map[string]tools.MCPTaskMode, len(o.perServer))
+		for k, v := range o.perServer {
+			cfg.PerServerMode[k] = tools.MCPTaskMode(v)
+		}
+	}
+	if o.progress != nil {
+		h := o.progress
+		cfg.Progress = func(p tools.MCPTaskProgress) {
+			h(MCPTaskProgress{
+				Server:  p.Server,
+				TaskID:  p.TaskID,
+				Status:  MCPTaskStatus(p.Status),
+				Message: p.Message,
+			})
+		}
+	}
+	return cfg
+}
+
+// ListMCPTasks queries tasks/list on the named MCP server and returns the
+// active and recent tasks the server is willing to disclose. Returns an
+// error when the server isn't loaded, doesn't expose tasks/list, or the
+// underlying transport fails.
+func (m *Kit) ListMCPTasks(ctx context.Context, serverName string) ([]MCPTask, error) {
+	mgr, err := m.mcpToolManager()
+	if err != nil {
+		return nil, err
+	}
+	infos, err := mgr.ListServerTasks(ctx, serverName)
+	if err != nil {
+		return nil, err
+	}
+	out := make([]MCPTask, len(infos))
+	for i, t := range infos {
+		out[i] = mcpTaskFromInternal(t)
+	}
+	return out, nil
+}
+
+// GetMCPTask queries tasks/get for a single in-flight task on the named
+// server. The returned MCPTask reflects the server's current view of the
+// task.
+func (m *Kit) GetMCPTask(ctx context.Context, serverName, taskID string) (MCPTask, error) {
+	mgr, err := m.mcpToolManager()
+	if err != nil {
+		return MCPTask{}, err
+	}
+	info, err := mgr.GetServerTask(ctx, serverName, taskID)
+	if err != nil {
+		return MCPTask{}, err
+	}
+	return mcpTaskFromInternal(info), nil
+}
+
+// CancelMCPTask issues tasks/cancel for an in-flight task on the named
+// server. Returns the post-cancel task state when the server responded
+// with one. Cancelling an already-terminal task is a no-op on most
+// servers.
+func (m *Kit) CancelMCPTask(ctx context.Context, serverName, taskID string) (MCPTask, error) {
+	mgr, err := m.mcpToolManager()
+	if err != nil {
+		return MCPTask{}, err
+	}
+	info, err := mgr.CancelServerTask(ctx, serverName, taskID)
+	if err != nil {
+		return MCPTask{}, err
+	}
+	return mcpTaskFromInternal(info), nil
+}
+
+// mcpToolManager returns the underlying MCP tool manager or an error when
+// no MCP servers are configured.
+func (m *Kit) mcpToolManager() (*tools.MCPToolManager, error) {
+	if m == nil || m.agent == nil {
+		return nil, fmt.Errorf("kit instance has no agent")
+	}
+	mgr := m.agent.GetMCPToolManager()
+	if mgr == nil {
+		return nil, fmt.Errorf("no MCP servers configured")
+	}
+	return mgr, nil
+}
+
+// mcpTaskFromInternal adapts the internal tools.MCPTaskInfo to the
+// SDK-level MCPTask type. Keeps the public surface independent of
+// internal package types.
+func mcpTaskFromInternal(t tools.MCPTaskInfo) MCPTask {
+	return MCPTask{
+		Server:        t.Server,
+		TaskID:        t.TaskID,
+		Status:        MCPTaskStatus(t.Status),
+		StatusMessage: t.StatusMessage,
+		CreatedAt:     t.CreatedAt,
+		UpdatedAt:     t.UpdatedAt,
+		TTL:           t.TTL,
+		PollInterval:  t.PollInterval,
+	}
+}
+
+// inheritMCPTaskOptions copies every MCP task-related field from parent
+// onto child. Used by Kit.Subagent so child instances observe the same
+// per-server modes, timeouts, and progress callback as their parent.
+// A nil parent is a no-op so callers don't have to guard at the call site.
+func inheritMCPTaskOptions(child, parent *Options) {
+	if child == nil || parent == nil {
+		return
+	}
+	child.MCPTaskMode = parent.MCPTaskMode
+	child.MCPTaskTimeout = parent.MCPTaskTimeout
+	child.MCPTaskTTL = parent.MCPTaskTTL
+	child.MCPTaskPollInterval = parent.MCPTaskPollInterval
+	child.MCPTaskMaxPollInterval = parent.MCPTaskMaxPollInterval
+	child.MCPTaskProgress = parent.MCPTaskProgress
+}

pkg/kit/mcp_tasks_test.go

@@ -0,0 +1,165 @@
+package kit
+
+import (
+	"testing"
+	"time"
+
+	"github.com/mark3labs/kit/internal/tools"
+)
+
+func TestMCPTaskStatusIsTerminal(t *testing.T) {
+	cases := []struct {
+		s    MCPTaskStatus
+		want bool
+	}{
+		{MCPTaskStatusWorking, false},
+		{MCPTaskStatusInputRequired, false},
+		{MCPTaskStatusCompleted, true},
+		{MCPTaskStatusFailed, true},
+		{MCPTaskStatusCancelled, true},
+		{MCPTaskStatus("unknown"), false},
+	}
+	for _, tc := range cases {
+		if got := tc.s.IsTerminal(); got != tc.want {
+			t.Errorf("MCPTaskStatus(%q).IsTerminal() = %v, want %v", tc.s, got, tc.want)
+		}
+	}
+}
+
+func TestMCPTaskOptionsToToolsConfig(t *testing.T) {
+	called := 0
+	o := mcpTaskOptions{
+		perServer: map[string]MCPTaskMode{
+			"alpha": MCPTaskModeAlways,
+			"beta":  MCPTaskModeNever,
+		},
+		defaultTTL:      30 * time.Second,
+		pollInterval:    250 * time.Millisecond,
+		maxPollInterval: 2 * time.Second,
+		timeout:         5 * time.Minute,
+		progress:        func(p MCPTaskProgress) { called++ },
+	}
+	cfg := o.toToolsConfig()
+
+	if cfg.DefaultTTL != 30*time.Second {
+		t.Errorf("DefaultTTL = %v, want 30s", cfg.DefaultTTL)
+	}
+	if cfg.PollInterval != 250*time.Millisecond {
+		t.Errorf("PollInterval = %v, want 250ms", cfg.PollInterval)
+	}
+	if cfg.MaxPollInterval != 2*time.Second {
+		t.Errorf("MaxPollInterval = %v, want 2s", cfg.MaxPollInterval)
+	}
+	if cfg.Timeout != 5*time.Minute {
+		t.Errorf("Timeout = %v, want 5m", cfg.Timeout)
+	}
+	if cfg.PerServerMode["alpha"] != tools.MCPTaskModeAlways {
+		t.Errorf("PerServerMode[alpha] = %q, want always", cfg.PerServerMode["alpha"])
+	}
+	if cfg.PerServerMode["beta"] != tools.MCPTaskModeNever {
+		t.Errorf("PerServerMode[beta] = %q, want never", cfg.PerServerMode["beta"])
+	}
+
+	// Progress conversion: invoking the internal handler must call our
+	// SDK-level callback with the converted struct.
+	if cfg.Progress == nil {
+		t.Fatal("Progress callback was lost in conversion")
+	}
+	cfg.Progress(tools.MCPTaskProgress{
+		Server: "alpha",
+		TaskID: "t1",
+		Status: "working",
+	})
+	if called != 1 {
+		t.Errorf("expected SDK progress handler to be invoked once, got %d", called)
+	}
+}
+
+func TestMCPTaskFromInternal(t *testing.T) {
+	in := tools.MCPTaskInfo{
+		Server:        "srv",
+		TaskID:        "t-1",
+		Status:        "working",
+		StatusMessage: "phase 1",
+		CreatedAt:     time.Date(2026, 5, 4, 12, 0, 0, 0, time.UTC),
+		UpdatedAt:     time.Date(2026, 5, 4, 12, 0, 1, 0, time.UTC),
+		TTL:           5 * time.Minute,
+		PollInterval:  500 * time.Millisecond,
+	}
+	out := mcpTaskFromInternal(in)
+
+	if out.Server != "srv" || out.TaskID != "t-1" {
+		t.Errorf("identity fields not copied: %+v", out)
+	}
+	if out.Status != MCPTaskStatusWorking {
+		t.Errorf("Status = %q, want working", out.Status)
+	}
+	if out.StatusMessage != "phase 1" {
+		t.Errorf("StatusMessage = %q, want phase 1", out.StatusMessage)
+	}
+	if out.TTL != 5*time.Minute || out.PollInterval != 500*time.Millisecond {
+		t.Errorf("durations not copied: %+v", out)
+	}
+}
+
+func TestKitMCPTasksWithoutAgentReturnsError(t *testing.T) {
+	// A nil/zero Kit must not panic — task RPCs should surface a clear
+	// error instead. Useful for SDK consumers that try task ops on a Kit
+	// constructed without MCP servers.
+	var k *Kit
+	ctx := t.Context()
+	if _, err := k.ListMCPTasks(ctx, "any"); err == nil {
+		t.Error("ListMCPTasks on nil Kit should error")
+	}
+	if _, err := k.GetMCPTask(ctx, "any", "id"); err == nil {
+		t.Error("GetMCPTask on nil Kit should error")
+	}
+	if _, err := k.CancelMCPTask(ctx, "any", "id"); err == nil {
+		t.Error("CancelMCPTask on nil Kit should error")
+	}
+}
+
+func TestSubagentPropagatesMCPTaskOptions(t *testing.T) {
+	// Exercises the helper Kit.Subagent uses to copy MCP task options
+	// onto child Options. Calling the real helper (rather than
+	// duplicating its body in the test) means any new field added to
+	// the propagation list is picked up automatically by the
+	// equivalence assertion below.
+	parent := &Options{
+		MCPTaskMode: map[string]MCPTaskMode{
+			"build": MCPTaskModeAlways,
+			"chat":  MCPTaskModeNever,
+		},
+		MCPTaskTimeout:         30 * time.Minute,
+		MCPTaskTTL:             45 * time.Minute,
+		MCPTaskPollInterval:    750 * time.Millisecond,
+		MCPTaskMaxPollInterval: 4 * time.Second,
+		MCPTaskProgress:        func(MCPTaskProgress) {},
+	}
+
+	child := &Options{}
+	inheritMCPTaskOptions(child, parent)
+
+	if child.MCPTaskMode["build"] != MCPTaskModeAlways || child.MCPTaskMode["chat"] != MCPTaskModeNever {
+		t.Errorf("MCPTaskMode not propagated: got %+v", child.MCPTaskMode)
+	}
+	if child.MCPTaskTimeout != 30*time.Minute {
+		t.Errorf("MCPTaskTimeout = %v, want 30m", child.MCPTaskTimeout)
+	}
+	if child.MCPTaskTTL != 45*time.Minute {
+		t.Errorf("MCPTaskTTL = %v, want 45m", child.MCPTaskTTL)
+	}
+	if child.MCPTaskPollInterval != 750*time.Millisecond {
+		t.Errorf("MCPTaskPollInterval = %v, want 750ms", child.MCPTaskPollInterval)
+	}
+	if child.MCPTaskMaxPollInterval != 4*time.Second {
+		t.Errorf("MCPTaskMaxPollInterval = %v, want 4s", child.MCPTaskMaxPollInterval)
+	}
+	if child.MCPTaskProgress == nil {
+		t.Error("MCPTaskProgress not propagated")
+	}
+
+	// Nil parent is a no-op rather than a panic.
+	inheritMCPTaskOptions(&Options{}, nil)
+	inheritMCPTaskOptions(nil, parent)
+}

pkg/kit/runtime_skills_context_test.go

@@ -0,0 +1,342 @@
+package kit
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+	"sync"
+	"testing"
+
+	"github.com/mark3labs/kit/internal/agent"
+	"github.com/mark3labs/kit/internal/skills"
+)
+
+// TestAddSkill_AddsAndDeduplicates verifies that AddSkill registers new skills
+// and that re-adding a skill with the same Name replaces the existing entry
+// rather than appending a duplicate. agent is nil in these tests; the method
+// must still mutate the in-memory state and tolerate the absent agent.
+func TestAddSkill_AddsAndDeduplicates(t *testing.T) {
+	k := &Kit{basePrompt: "base"}
+
+	if err := k.AddSkill(&skills.Skill{Name: "alpha", Content: "first"}); err != nil {
+		t.Fatalf("AddSkill alpha: %v", err)
+	}
+	if err := k.AddSkill(&skills.Skill{Name: "beta", Content: "second"}); err != nil {
+		t.Fatalf("AddSkill beta: %v", err)
+	}
+	got := k.GetSkills()
+	if len(got) != 2 {
+		t.Fatalf("expected 2 skills, got %d", len(got))
+	}
+
+	// Re-adding alpha with new content must replace, not duplicate.
+	if err := k.AddSkill(&skills.Skill{Name: "alpha", Content: "replaced"}); err != nil {
+		t.Fatalf("AddSkill alpha replace: %v", err)
+	}
+	got = k.GetSkills()
+	if len(got) != 2 {
+		t.Fatalf("expected 2 skills after replace, got %d", len(got))
+	}
+	for _, s := range got {
+		if s.Name == "alpha" && s.Content != "replaced" {
+			t.Errorf("alpha content = %q; want %q", s.Content, "replaced")
+		}
+	}
+}
+
+// TestAddSkill_Validation rejects nil skills and unnamed skills with errors
+// instead of corrupting state.
+func TestAddSkill_Validation(t *testing.T) {
+	k := &Kit{}
+	if err := k.AddSkill(nil); err == nil {
+		t.Error("expected error for nil skill")
+	}
+	if err := k.AddSkill(&skills.Skill{Content: "x"}); err == nil {
+		t.Error("expected error for unnamed skill")
+	}
+	if got := k.GetSkills(); got != nil {
+		t.Errorf("skills list mutated after invalid AddSkill calls: %#v", got)
+	}
+}
+
+// TestRemoveSkill verifies removal and the false return for misses.
+func TestRemoveSkill(t *testing.T) {
+	k := &Kit{}
+	_ = k.AddSkill(&skills.Skill{Name: "alpha"})
+	_ = k.AddSkill(&skills.Skill{Name: "beta"})
+
+	if removed := k.RemoveSkill("missing"); removed {
+		t.Error("RemoveSkill(missing) = true; want false")
+	}
+	if removed := k.RemoveSkill("alpha"); !removed {
+		t.Error("RemoveSkill(alpha) = false; want true")
+	}
+	got := k.GetSkills()
+	if len(got) != 1 || got[0].Name != "beta" {
+		t.Errorf("remaining skills = %#v; want [beta]", got)
+	}
+}
+
+// TestSetSkills replaces the entire set and validates input.
+func TestSetSkills(t *testing.T) {
+	k := &Kit{}
+	_ = k.AddSkill(&skills.Skill{Name: "alpha"})
+
+	err := k.SetSkills([]*skills.Skill{
+		{Name: "one"},
+		{Name: "two"},
+		{Name: "three"},
+	})
+	if err != nil {
+		t.Fatalf("SetSkills: %v", err)
+	}
+	if got := k.GetSkills(); len(got) != 3 {
+		t.Errorf("expected 3 skills, got %d", len(got))
+	}
+
+	// Invalid entry rejects the whole batch.
+	bad := []*skills.Skill{{Name: "ok"}, nil}
+	if err := k.SetSkills(bad); err == nil {
+		t.Error("expected error when batch contains nil")
+	}
+	// State unchanged after rejected batch.
+	if got := k.GetSkills(); len(got) != 3 {
+		t.Errorf("skills mutated by rejected SetSkills batch: len=%d", len(got))
+	}
+
+	// Empty slice clears.
+	if err := k.SetSkills(nil); err != nil {
+		t.Fatalf("SetSkills(nil): %v", err)
+	}
+	if got := k.GetSkills(); got != nil {
+		t.Errorf("expected nil skills after clear; got %#v", got)
+	}
+}
+
+// TestLoadAndAddSkill round-trips a skill file from disk.
+func TestLoadAndAddSkill(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "demo.md")
+	body := "---\nname: demo\ndescription: demo skill\n---\nhello world"
+	if err := os.WriteFile(path, []byte(body), 0o644); err != nil {
+		t.Fatalf("write skill file: %v", err)
+	}
+
+	k := &Kit{}
+	s, err := k.LoadAndAddSkill(path)
+	if err != nil {
+		t.Fatalf("LoadAndAddSkill: %v", err)
+	}
+	if s.Name != "demo" {
+		t.Errorf("loaded skill Name = %q; want demo", s.Name)
+	}
+	if got := k.GetSkills(); len(got) != 1 {
+		t.Errorf("expected 1 skill registered, got %d", len(got))
+	}
+}
+
+// TestAddContextFile_DeduplicatesByPath confirms identical paths replace
+// rather than duplicate.
+func TestAddContextFile_DeduplicatesByPath(t *testing.T) {
+	k := &Kit{}
+	if err := k.AddContextFile(&ContextFile{Path: "/a/AGENTS.md", Content: "v1"}); err != nil {
+		t.Fatalf("AddContextFile: %v", err)
+	}
+	if err := k.AddContextFile(&ContextFile{Path: "/b/AGENTS.md", Content: "vB"}); err != nil {
+		t.Fatalf("AddContextFile: %v", err)
+	}
+	if err := k.AddContextFile(&ContextFile{Path: "/a/AGENTS.md", Content: "v2"}); err != nil {
+		t.Fatalf("AddContextFile replace: %v", err)
+	}
+
+	got := k.GetContextFiles()
+	if len(got) != 2 {
+		t.Fatalf("expected 2 context files, got %d", len(got))
+	}
+	for _, cf := range got {
+		if cf.Path == "/a/AGENTS.md" && cf.Content != "v2" {
+			t.Errorf("/a/AGENTS.md content = %q; want v2", cf.Content)
+		}
+	}
+}
+
+// TestAddContextFile_Validation rejects nil and unpathed entries.
+func TestAddContextFile_Validation(t *testing.T) {
+	k := &Kit{}
+	if err := k.AddContextFile(nil); err == nil {
+		t.Error("expected error for nil context file")
+	}
+	if err := k.AddContextFile(&ContextFile{Content: "x"}); err == nil {
+		t.Error("expected error for empty path")
+	}
+}
+
+// TestRemoveContextFile_Behavior verifies remove returns true on hit and
+// false on miss without mutating state on a miss.
+func TestRemoveContextFile_Behavior(t *testing.T) {
+	k := &Kit{}
+	_ = k.AddContextFile(&ContextFile{Path: "/a", Content: "x"})
+	_ = k.AddContextFile(&ContextFile{Path: "/b", Content: "y"})
+
+	if removed := k.RemoveContextFile("/missing"); removed {
+		t.Error("RemoveContextFile(missing) = true; want false")
+	}
+	if removed := k.RemoveContextFile("/a"); !removed {
+		t.Error("RemoveContextFile(/a) = false; want true")
+	}
+	got := k.GetContextFiles()
+	if len(got) != 1 || got[0].Path != "/b" {
+		t.Errorf("remaining = %#v; want [/b]", got)
+	}
+}
+
+// TestSetContextFiles replaces and validates batch input.
+func TestSetContextFiles(t *testing.T) {
+	k := &Kit{}
+	_ = k.AddContextFile(&ContextFile{Path: "/seed", Content: "old"})
+
+	err := k.SetContextFiles([]*ContextFile{
+		{Path: "/x", Content: "x"},
+		{Path: "/y", Content: "y"},
+	})
+	if err != nil {
+		t.Fatalf("SetContextFiles: %v", err)
+	}
+	if got := k.GetContextFiles(); len(got) != 2 {
+		t.Errorf("expected 2 context files, got %d", len(got))
+	}
+
+	bad := []*ContextFile{{Path: "/ok"}, {Path: ""}}
+	if err := k.SetContextFiles(bad); err == nil {
+		t.Error("expected error for empty path in batch")
+	}
+	if got := k.GetContextFiles(); len(got) != 2 {
+		t.Errorf("state mutated by rejected batch: len=%d", len(got))
+	}
+
+	if err := k.SetContextFiles(nil); err != nil {
+		t.Fatalf("SetContextFiles(nil): %v", err)
+	}
+	if got := k.GetContextFiles(); got != nil {
+		t.Errorf("expected nil after clear; got %#v", got)
+	}
+}
+
+// TestLoadAndAddContextFile reads from disk and registers the context file.
+func TestLoadAndAddContextFile(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "AGENTS.md")
+	const content = "# Agent rules\nuse the new lint config"
+	if err := os.WriteFile(path, []byte(content), 0o644); err != nil {
+		t.Fatalf("write file: %v", err)
+	}
+
+	k := &Kit{}
+	cf, err := k.LoadAndAddContextFile(path)
+	if err != nil {
+		t.Fatalf("LoadAndAddContextFile: %v", err)
+	}
+	if !strings.HasSuffix(cf.Path, "AGENTS.md") {
+		t.Errorf("Path = %q; want suffix AGENTS.md", cf.Path)
+	}
+	if !strings.Contains(cf.Content, "use the new lint config") {
+		t.Errorf("Content missing expected body: %q", cf.Content)
+	}
+	got := k.GetContextFiles()
+	if len(got) != 1 {
+		t.Fatalf("expected 1 context file, got %d", len(got))
+	}
+}
+
+// TestAddContextFileContent registers an in-memory context blob.
+func TestAddContextFileContent(t *testing.T) {
+	k := &Kit{}
+	cf, err := k.AddContextFileContent("session://user-123/AGENTS.md", "always greet in French")
+	if err != nil {
+		t.Fatalf("AddContextFileContent: %v", err)
+	}
+	if cf.Path != "session://user-123/AGENTS.md" {
+		t.Errorf("Path = %q", cf.Path)
+	}
+	if cf.Content != "always greet in French" {
+		t.Errorf("Content = %q", cf.Content)
+	}
+}
+
+// TestComposeSystemPrompt_IncludesSkillsAndContext verifies that runtime
+// mutations actually flow into the composed system prompt that the agent
+// would receive.
+func TestComposeSystemPrompt_IncludesSkillsAndContext(t *testing.T) {
+	k := &Kit{basePrompt: "BASE-PROMPT-MARKER"}
+
+	if err := k.AddContextFile(&ContextFile{
+		Path:    "/proj/AGENTS.md",
+		Content: "CTX-MARKER-OK",
+	}); err != nil {
+		t.Fatalf("AddContextFile: %v", err)
+	}
+	if err := k.AddSkill(&skills.Skill{
+		Name:        "greeter",
+		Description: "SKILL-DESC-MARKER",
+		Content:     "do greetings",
+		Path:        "/skills/greeter.md",
+	}); err != nil {
+		t.Fatalf("AddSkill: %v", err)
+	}
+
+	composed := k.composeSystemPrompt(k.basePrompt)
+	for _, want := range []string{
+		"BASE-PROMPT-MARKER",
+		"CTX-MARKER-OK",
+		"/proj/AGENTS.md",
+		"greeter",
+		"SKILL-DESC-MARKER",
+	} {
+		if !strings.Contains(composed, want) {
+			t.Errorf("composed prompt missing %q\n--- composed ---\n%s", want, composed)
+		}
+	}
+
+	// Removing the skill should remove its marker from the next composition.
+	k.RemoveSkill("greeter")
+	composed = k.composeSystemPrompt(k.basePrompt)
+	if strings.Contains(composed, "SKILL-DESC-MARKER") {
+		t.Errorf("composed prompt still contains removed skill description:\n%s", composed)
+	}
+}
+
+// TestRuntimeMutations_AreThreadSafe stresses the mutation API from multiple
+// goroutines to surface data races under `go test -race`.
+func TestRuntimeMutations_AreThreadSafe(t *testing.T) {
+	// Use a non-nil agent so applyComposedSystemPrompt actually invokes
+	// agent.SetSystemPrompt (a no-op agent is fine — we only need the
+	// systemPrompt mutation + fantasy rebuild path to run concurrently so
+	// -race can observe any unsynchronized writes).
+	k := &Kit{basePrompt: "base", agent: &agent.Agent{}}
+	var wg sync.WaitGroup
+	const goroutines = 8
+	const iterations = 50
+
+	for g := range goroutines {
+		wg.Add(1)
+		go func(id int) {
+			defer wg.Done()
+			for range iterations {
+				_ = k.AddSkill(&skills.Skill{
+					Name:    "skill",
+					Content: "content",
+				})
+				_ = k.AddContextFile(&ContextFile{
+					Path:    "/shared/AGENTS.md",
+					Content: "shared",
+				})
+				_ = k.GetSkills()
+				_ = k.GetContextFiles()
+				_ = k.composeSystemPrompt("base")
+				k.RemoveSkill("skill")
+				k.RemoveContextFile("/shared/AGENTS.md")
+			}
+		}(g)
+	}
+	wg.Wait()
+}

pkg/kit/skills.go

@@ -139,13 +139,150 @@ func (m *Kit) ClearSkillCache() {
 }
 
 // ReloadSkills re-discovers skills from disk, replacing the current set.
-// This is called by file watchers when skill files change.
+// This is called by file watchers when skill files change. The system prompt
+// is recomposed and applied to the running agent so subsequent turns see the
+// new skill set.
 func (m *Kit) ReloadSkills() error {
 	newSkills, err := loadSkills(m.opts)
 	if err != nil {
 		return fmt.Errorf("reloading skills: %w", err)
 	}
+	m.runtimeMu.Lock()
 	m.skills = newSkills
+	m.runtimeMu.Unlock()
 	m.ClearSkillCache()
+	m.applyComposedSystemPrompt()
 	return nil
 }
+
+// ---------------------------------------------------------------------------
+// Runtime skill management (Issue #36)
+// ---------------------------------------------------------------------------
+//
+// The methods below let SDK consumers (chatbot hosts, multi-tenant agents)
+// mutate the active skill set after Kit construction. Each mutation recomposes
+// the system prompt and applies it to the underlying agent so the LLM sees
+// the new skill metadata on its next turn.
+
+// AddSkill registers a single skill on this Kit instance. The skill object
+// can be built programmatically (no file on disk required) — only Name and
+// Content are mandatory. If a skill with the same Name is already loaded the
+// new skill replaces it. Returns an error when skill is nil or has an empty
+// name.
+//
+// After mutation the system prompt is recomposed and applied to the running
+// agent so the next turn sees the updated skill metadata. AddSkill is safe to
+// call from any goroutine.
+func (m *Kit) AddSkill(skill *Skill) error {
+	if skill == nil {
+		return fmt.Errorf("AddSkill: skill is nil")
+	}
+	if skill.Name == "" {
+		return fmt.Errorf("AddSkill: skill name is required")
+	}
+
+	m.runtimeMu.Lock()
+	replaced := false
+	for i, s := range m.skills {
+		if s.Name == skill.Name {
+			m.skills[i] = skill
+			replaced = true
+			break
+		}
+	}
+	if !replaced {
+		m.skills = append(m.skills, skill)
+	}
+	m.runtimeMu.Unlock()
+
+	m.ClearSkillCache()
+	m.applyComposedSystemPrompt()
+	return nil
+}
+
+// LoadAndAddSkill loads a skill from a filesystem path (single .md/.txt file)
+// and adds it via [Kit.AddSkill]. Returns the loaded skill on success.
+func (m *Kit) LoadAndAddSkill(path string) (*Skill, error) {
+	s, err := skills.LoadSkill(path)
+	if err != nil {
+		return nil, fmt.Errorf("LoadAndAddSkill: %w", err)
+	}
+	if err := m.AddSkill(s); err != nil {
+		return nil, err
+	}
+	return s, nil
+}
+
+// RemoveSkill removes the named skill from this Kit instance and recomposes
+// the system prompt. Returns true when a skill with that name was found and
+// removed, false otherwise.
+func (m *Kit) RemoveSkill(name string) bool {
+	m.runtimeMu.Lock()
+	found := false
+	for i, s := range m.skills {
+		if s.Name == name {
+			m.skills = append(m.skills[:i], m.skills[i+1:]...)
+			found = true
+			break
+		}
+	}
+	m.runtimeMu.Unlock()
+
+	if !found {
+		return false
+	}
+	m.ClearSkillCache()
+	m.applyComposedSystemPrompt()
+	return true
+}
+
+// SetSkills replaces the active skill set with the provided slice. Pass nil
+// or an empty slice to remove all skills. The system prompt is recomposed and
+// applied. Skills with empty names are rejected and no mutation is performed.
+func (m *Kit) SetSkills(skillList []*Skill) error {
+	// Validate first so a bad input doesn't partially mutate state.
+	for i, s := range skillList {
+		if s == nil {
+			return fmt.Errorf("SetSkills: skill at index %d is nil", i)
+		}
+		if s.Name == "" {
+			return fmt.Errorf("SetSkills: skill at index %d has empty name", i)
+		}
+	}
+
+	copied := make([]*Skill, len(skillList))
+	copy(copied, skillList)
+
+	m.runtimeMu.Lock()
+	m.skills = copied
+	m.runtimeMu.Unlock()
+
+	m.ClearSkillCache()
+	m.applyComposedSystemPrompt()
+	return nil
+}
+
+// applyComposedSystemPrompt recomposes the system prompt from the captured
+// base prompt + current contextFiles + current skills + date/cwd, and pushes
+// the result onto the underlying agent. No-op when the agent is unset (i.e.
+// during construction).
+func (m *Kit) applyComposedSystemPrompt() {
+	if m.agent == nil {
+		return
+	}
+	m.runtimeMu.RLock()
+	base := m.basePrompt
+	m.runtimeMu.RUnlock()
+	composed := m.composeSystemPrompt(base)
+	m.agent.SetSystemPrompt(composed)
+}
+
+// RefreshSystemPrompt manually recomposes the system prompt from the current
+// skills and context files and applies it to the agent. Call this after a
+// batch of low-level mutations or to force a re-render of the date/cwd
+// section. Most callers don't need to invoke this directly because
+// AddSkill, RemoveSkill, SetSkills, AddContextFile, RemoveContextFile, and
+// SetContextFiles all refresh automatically.
+func (m *Kit) RefreshSystemPrompt() {
+	m.applyComposedSystemPrompt()
+}

pkg/kit/types.go

@@ -11,6 +11,7 @@ import (
 	"github.com/mark3labs/kit/internal/message"
 	"github.com/mark3labs/kit/internal/models"
 	"github.com/mark3labs/kit/internal/session"
+	"github.com/mark3labs/kit/internal/tools"
 	"github.com/mark3labs/mcp-go/client/transport"
 	"github.com/mark3labs/mcp-go/server"
 )
@@ -75,25 +76,151 @@ type Config = config.Config
 // local (stdio) and remote (StreamableHTTP/SSE) server types.
 type MCPServerConfig = config.MCPServerConfig
 
-// ==== Agent Types (internal/agent/) ====
+// ==== Agent Types ====
 
-// AgentConfig holds configuration options for creating a new Agent.
-type AgentConfig = agent.AgentConfig
+// DebugLogger is an SDK-owned interface for low-level debug logging from
+// the engine and MCP tool plumbing. Implementations must be safe for
+// concurrent use.
+//
+// Most consumers do not need to provide one; pass [Options.Debug] = true
+// to use the default logger. DebugLogger is exposed for the low-level
+// [AgentConfig] path and for embedders that want to route debug output
+// into their own logging system.
+type DebugLogger interface {
+	// LogDebug records a single debug message. Implementations may drop,
+	// buffer, or render the message however they choose.
+	LogDebug(message string)
+	// IsDebugEnabled reports whether debug logging is active. Callers may
+	// check this before doing expensive formatting work.
+	IsDebugEnabled() bool
+}
 
-type (
-	// ToolCallHandler is a function type for handling tool calls as they happen.
-	ToolCallHandler = agent.ToolCallHandler
-	// ToolExecutionHandler is a function type for handling tool execution start/end events.
-	ToolExecutionHandler = agent.ToolExecutionHandler
-	// ToolResultHandler is a function type for handling tool results.
-	ToolResultHandler = agent.ToolResultHandler
-	// ResponseHandler is a function type for handling LLM responses.
-	ResponseHandler = agent.ResponseHandler
-	// StreamingResponseHandler is a function type for handling streaming LLM responses.
-	StreamingResponseHandler = agent.StreamingResponseHandler
-	// ToolCallContentHandler is a function type for handling content that accompanies tool calls.
-	ToolCallContentHandler = agent.ToolCallContentHandler
-)
+// AgentConfig holds configuration options for constructing an agent at the
+// SDK boundary. All fields use SDK-owned types, so consumers can populate
+// this struct without importing any underlying LLM-provider package.
+//
+// For most use cases, prefer the high-level [New] entry point with
+// [Options]. AgentConfig is exposed for advanced consumers that need
+// direct access to the lower-level agent configuration shape.
+type AgentConfig struct {
+	// ModelConfig holds the LLM provider configuration. A nil value means
+	// that the default provider/model resolution will be used.
+	ModelConfig *ProviderConfig
+
+	// MCPConfig describes any MCP servers whose tools should be loaded
+	// alongside core tools.
+	MCPConfig *Config
+
+	// SystemPrompt is the system prompt sent to the LLM.
+	SystemPrompt string
+
+	// MaxSteps caps the number of LLM iterations per turn. A value of
+	// zero means no cap is applied at this layer.
+	MaxSteps int
+
+	// StreamingEnabled controls whether the agent streams responses.
+	StreamingEnabled bool
+
+	// AuthHandler handles OAuth authorization for remote MCP servers.
+	// When nil, remote MCP servers requiring OAuth will fail to connect.
+	AuthHandler MCPAuthHandler
+
+	// TokenStoreFactory, if non-nil, creates a custom token store for each
+	// remote MCP server's OAuth tokens. When nil, the default file-based
+	// token store is used.
+	TokenStoreFactory MCPTokenStoreFactory
+
+	// CoreTools overrides the default core tool set. If empty, [AllTools]
+	// is used. Provide a custom tool set (e.g. [CodingTools] or tools
+	// built with a custom WorkDir) to scope agent capabilities.
+	CoreTools []Tool
+
+	// DisableCoreTools, when true, prevents loading any core tools.
+	// Combined with empty CoreTools this yields a chat-only agent with
+	// no built-in tools.
+	DisableCoreTools bool
+
+	// ExtraTools are additional tools loaded alongside core and MCP tools.
+	ExtraTools []Tool
+
+	// ToolWrapper, if non-nil, wraps the combined tool list before it is
+	// handed to the LLM. Used to intercept tool calls or results.
+	ToolWrapper func([]Tool) []Tool
+
+	// OnMCPServerLoaded, if non-nil, is invoked once for each MCP server
+	// when its tools have finished loading (or failed). Called from a
+	// background goroutine.
+	OnMCPServerLoaded func(serverName string, toolCount int, err error)
+
+	// DebugLogger receives low-level debug output from the engine and the
+	// MCP tool plumbing. Nil means no debug output is emitted at this
+	// layer (regardless of [Options.Debug], which feeds the higher-level
+	// [New] entry point). Pass an implementation here when wiring a custom
+	// logger through the lower-level AgentConfig path.
+	DebugLogger DebugLogger
+
+	// MCPTaskConfig configures task-aware MCP tools/call execution — mode
+	// overrides, polling intervals, timeouts, and the progress handler.
+	// The zero value preserves historical synchronous-only behaviour for
+	// any server that didn't advertise task support during initialize.
+	MCPTaskConfig MCPTaskConfig
+}
+
+// toInternal converts an AgentConfig to its internal representation.
+// Slice and function fields convert without allocation because [Tool]
+// is a type alias for the underlying LLM-tool type.
+func (c *AgentConfig) toInternal() *agent.AgentConfig {
+	if c == nil {
+		return nil
+	}
+	out := &agent.AgentConfig{
+		ModelConfig:       c.ModelConfig,
+		MCPConfig:         c.MCPConfig,
+		SystemPrompt:      c.SystemPrompt,
+		MaxSteps:          c.MaxSteps,
+		StreamingEnabled:  c.StreamingEnabled,
+		CoreTools:         c.CoreTools,
+		DisableCoreTools:  c.DisableCoreTools,
+		ExtraTools:        c.ExtraTools,
+		ToolWrapper:       c.ToolWrapper,
+		OnMCPServerLoaded: c.OnMCPServerLoaded,
+	}
+	if c.AuthHandler != nil {
+		out.AuthHandler = c.AuthHandler
+	}
+	if c.TokenStoreFactory != nil {
+		out.TokenStoreFactory = tools.TokenStoreFactory(c.TokenStoreFactory)
+	}
+	if c.DebugLogger != nil {
+		out.DebugLogger = c.DebugLogger
+	}
+	out.MCPTaskConfig = c.MCPTaskConfig.toToolsConfig()
+	return out
+}
+
+// ToolCallHandler is invoked when the LLM produces a tool call. It receives
+// the call ID, tool name, and the JSON-encoded input arguments.
+type ToolCallHandler func(toolCallID, toolName, toolArgs string)
+
+// ToolExecutionHandler is invoked at the start and end of tool execution.
+// The isStarting flag distinguishes the two phases.
+type ToolExecutionHandler func(toolCallID, toolName, toolArgs string, isStarting bool)
+
+// ToolResultHandler is invoked after a tool finishes executing. The metadata
+// parameter carries optional structured data (e.g. file-diff info) from the
+// tool execution, JSON-encoded; it may be empty.
+type ToolResultHandler func(toolCallID, toolName, toolArgs, result, metadata string, isError bool)
+
+// ResponseHandler is invoked with the final assistant text for each turn.
+type ResponseHandler func(content string)
+
+// StreamingResponseHandler is invoked with each streamed text delta as it
+// arrives from the LLM.
+type StreamingResponseHandler func(content string)
+
+// ToolCallContentHandler is invoked with any assistant text that accompanies
+// a tool call within the same step.
+type ToolCallContentHandler func(content string)
 
 // ==== Provider & Model Types (internal/models/) ====
 
@@ -126,7 +253,7 @@ type ModelsRegistry = models.ModelsRegistry
 
 // SpinnerFunc wraps a function in a loading spinner animation. Used for
 // Ollama model loading. Signature: func(fn func() error) error.
-type SpinnerFunc = agent.SpinnerFunc
+type SpinnerFunc func(fn func() error) error
 
 // ==== LLM Types ====
 //

pkg/kit/types_test.go

@@ -1,6 +1,7 @@
 package kit_test
 
 import (
+	"context"
 	"encoding/json"
 	"testing"
 
@@ -263,6 +264,101 @@ func TestConvertFromLLMMessage(t *testing.T) {
 	}
 }
 
+// TestAgentConfigNoFantasyImport verifies AgentConfig can be populated with
+// every field — including CoreTools, ExtraTools, and ToolWrapper — using
+// only SDK-owned types. This test deliberately does not import
+// "charm.land/fantasy"; the package compiling at all is the proof that the
+// SDK no longer leaks the dependency name through AgentConfig.
+//
+// Regression test for https://github.com/mark3labs/kit/issues/30.
+func TestAgentConfigNoFantasyImport(t *testing.T) {
+	myTool := kit.NewTool[struct{}]("noop", "does nothing", func(_ context.Context, _ struct{}) (kit.ToolOutput, error) {
+		return kit.TextResult("ok"), nil
+	})
+
+	wrapperCalled := false
+	cfg := kit.AgentConfig{
+		SystemPrompt:     "you are a tester",
+		MaxSteps:         5,
+		StreamingEnabled: true,
+		CoreTools:        []kit.Tool{myTool},
+		ExtraTools:       []kit.Tool{myTool},
+		DisableCoreTools: false,
+		ToolWrapper: func(in []kit.Tool) []kit.Tool {
+			wrapperCalled = true
+			return in
+		},
+		OnMCPServerLoaded: func(_ string, _ int, _ error) {},
+	}
+
+	if cfg.SystemPrompt != "you are a tester" {
+		t.Errorf("SystemPrompt = %q, want %q", cfg.SystemPrompt, "you are a tester")
+	}
+	if cfg.MaxSteps != 5 {
+		t.Errorf("MaxSteps = %d, want 5", cfg.MaxSteps)
+	}
+	if !cfg.StreamingEnabled {
+		t.Error("StreamingEnabled = false, want true")
+	}
+	if len(cfg.CoreTools) != 1 {
+		t.Errorf("CoreTools len = %d, want 1", len(cfg.CoreTools))
+	}
+	if len(cfg.ExtraTools) != 1 {
+		t.Errorf("ExtraTools len = %d, want 1", len(cfg.ExtraTools))
+	}
+
+	// Exercise the wrapper to confirm the func type is usable.
+	out := cfg.ToolWrapper(cfg.CoreTools)
+	if !wrapperCalled {
+		t.Error("ToolWrapper was not invoked")
+	}
+	if len(out) != 1 {
+		t.Errorf("wrapped tool list len = %d, want 1", len(out))
+	}
+}
+
+// TestAgentConfigToolWrapperSignature documents that AgentConfig.ToolWrapper
+// uses kit.Tool (not the underlying provider type) in its signature.
+func TestAgentConfigToolWrapperSignature(t *testing.T) {
+	//nolint:staticcheck // QF1011: explicit type asserts the SDK-side func signature.
+	var _ func([]kit.Tool) []kit.Tool = func(in []kit.Tool) []kit.Tool { return in }
+	cfg := kit.AgentConfig{
+		ToolWrapper: func(in []kit.Tool) []kit.Tool { return in },
+	}
+	if cfg.ToolWrapper == nil {
+		t.Fatal("ToolWrapper assignment failed")
+	}
+}
+
+// TestSpinnerFuncSignature verifies SpinnerFunc has the documented signature
+// and can be constructed without importing any provider package.
+func TestSpinnerFuncSignature(t *testing.T) {
+	called := false
+	var sp kit.SpinnerFunc = func(fn func() error) error {
+		called = true
+		return fn()
+	}
+	err := sp(func() error { return nil })
+	if err != nil {
+		t.Errorf("SpinnerFunc returned err: %v", err)
+	}
+	if !called {
+		t.Error("SpinnerFunc did not invoke fn")
+	}
+}
+
+// TestHandlerTypesSignatures verifies the SDK-owned handler function types
+// can be assigned from plain function literals using only standard library
+// types in their signatures (no provider-package import required).
+func TestHandlerTypesSignatures(t *testing.T) {
+	var _ kit.ToolCallHandler = func(_, _, _ string) {}
+	var _ kit.ToolExecutionHandler = func(_, _, _ string, _ bool) {}
+	var _ kit.ToolResultHandler = func(_, _, _, _, _ string, _ bool) {}
+	var _ kit.ResponseHandler = func(_ string) {}
+	var _ kit.StreamingResponseHandler = func(_ string) {}
+	var _ kit.ToolCallContentHandler = func(_ string) {}
+}
+
 // containsStr is a tiny helper to avoid importing strings in test.
 func containsStr(s, substr string) bool {
 	return len(s) >= len(substr) && (s == substr || len(s) > 0 && indexStr(s, substr) >= 0)

specs/README.md

@@ -1,5 +0,0 @@
-# Specs
-
-| Spec | Status | Description |
-|------|--------|-------------|
-| [unified-bubbletea-architecture](unified-bubbletea-architecture.md) | Draft | Replace micro-program pattern with single Bubble Tea program + thick app layer |

www/pages/configuration.md

@@ -88,6 +88,11 @@ mcpServers:
     type: remote
     url: "https://pubmed.mcp.example.com"
     noOAuth: true  # skip OAuth for public servers
+
+  builds:
+    type: remote
+    url: "https://builds.mcp.example.com"
+    tasksMode: always  # always run tools/call as async tasks (Phase 1 MVP)
 ```
 
 ### MCP server fields
@@ -101,9 +106,34 @@ mcpServers:
 | `allowedTools` | list | Whitelist of tool names to expose |
 | `excludedTools` | list | Blacklist of tool names to hide |
 | `noOAuth` | bool | Skip OAuth for this server (for public servers that don't require auth) |
+| `tasksMode` | string | When to augment `tools/call` with MCP task metadata: `auto` (default — only when the server advertises task support), `never`, or `always`. See [MCP tasks](#mcp-tasks-long-running-tools). |
 
 A legacy format with `transport`, `args`, `env`, and `headers` fields is also supported.
 
+### MCP tasks (long-running tools)
+
+Kit advertises [MCP task support](https://modelcontextprotocol.io/specification/2025-11-25/basic/utilities/tasks)
+during `initialize` so servers can respond to `tools/call` with a
+`CreateTaskResult` (a task ID + `working` status) instead of blocking until
+the operation finishes. Kit then polls `tasks/get` / `tasks/result` until the
+task reaches a terminal state, and best-effort `tasks/cancel`s on context
+cancellation.
+
+This avoids HTTP/SSE proxy timeouts on long builds, deploys, and batch jobs,
+and lets the user/agent abort cleanly with Ctrl-C.
+
+**Per-server `tasksMode`:**
+
+| Value | Behaviour |
+|-------|-----------|
+| `auto` (default) | Augment `tools/call` with task metadata only when the server advertised `tasks/toolCalls` capability. Servers that don't advertise it run synchronously, exactly as before. |
+| `never` | Always issue `tools/call` synchronously, regardless of server capability. |
+| `always` | Always opt into task augmentation, even when the server didn't advertise the capability. The server may still respond synchronously — this just expresses client intent unconditionally. |
+
+Defaults are safe: any existing MCP server keeps its previous behaviour
+bit-for-bit. SDK consumers can also override the mode programmatically and
+plug in a progress callback — see [SDK options](/sdk/options#mcp-tasks).
+
 ## Custom models
 
 Define custom models in your `.kit.yml` for use with the `custom` provider. This is useful for self-hosted models or API endpoints not in the built-in database:

www/pages/sdk/options.md

@@ -160,6 +160,14 @@ when embedding Kit as a library.
 | `SkillsDir` | `string` | — | Override default skills directory |
 | `NoSkills` | `bool` | `false` | Disable skill loading entirely |
 
+These fields only control the **initial** skill and context-file set picked
+up by `New()`. To add, remove, or replace skills and `AGENTS.md`-style
+context files at runtime (e.g. per user or per session), use the
+`AddSkill` / `LoadAndAddSkill` / `RemoveSkill` / `SetSkills` and
+`AddContextFile` / `AddContextFileContent` / `RemoveContextFile` /
+`SetContextFiles` methods on `*kit.Kit`. See
+[Runtime skills and context files](/sdk/overview#runtime-skills-and-context-files).
+
 ### Compaction & MCP
 
 | Field | Type | Default | Description |
@@ -169,6 +177,12 @@ when embedding Kit as a library.
 | `MCPAuthHandler` | `MCPAuthHandler` | — | OAuth handler for remote MCP servers. `nil` disables OAuth (servers returning 401 fail with the authorization-required error). See [MCP OAuth](#mcp-oauth-authorization) below. |
 | `MCPTokenStoreFactory` | `func` | — | Custom OAuth token storage for MCP servers (default: JSON file in `$XDG_CONFIG_HOME/.kit/mcp_tokens.json`). |
 | `InProcessMCPServers` | `map[string]*MCPServer` | — | In-process mcp-go servers (no subprocess) |
+| `MCPTaskMode` | `map[string]MCPTaskMode` | — | Per-server override for task-augmented `tools/call`. Keys are server names; missing entries fall back to the `tasksMode` field of the matching `MCPServerConfig`. See [MCP Tasks](#mcp-tasks). |
+| `MCPTaskTimeout` | `time.Duration` | `15m` | Maximum wall-clock to wait for a task to reach a terminal state. Independent of any per-call context deadline. |
+| `MCPTaskTTL` | `time.Duration` | — | TTL hint sent in `TaskParams` for every task-augmented call. Zero omits the field and lets the server pick. |
+| `MCPTaskPollInterval` | `time.Duration` | `1s` | Fallback interval between `tasks/get` requests when the server does not suggest one. |
+| `MCPTaskMaxPollInterval` | `time.Duration` | `5s` | Cap on the polling interval (a server-supplied `pollInterval` can otherwise grow without bound). |
+| `MCPTaskProgress` | `MCPTaskProgressHandler` | — | Optional callback invoked once when a task is accepted and on every observed status transition. The final invocation always carries a terminal status. |
 
 ## MCP OAuth Authorization
 
@@ -248,6 +262,79 @@ authorization URL and hang until the 2-minute callback timeout fires. Always
 set `OnAuthURL`, or use a higher-level wrapper like `CLIMCPAuthHandler`.
 :::
 
+## MCP Tasks
+
+The [MCP Tasks utility](https://modelcontextprotocol.io/specification/2025-11-25/basic/utilities/tasks)
+turns a synchronous `tools/call` into a pollable async job: the server
+returns a `taskId` with status `working` immediately, and the client polls
+`tasks/get` / `tasks/result` until the task reaches a terminal state.
+
+Kit advertises task support during `initialize` and, by default, augments
+`tools/call` with task metadata only when the server advertises
+`tasks/toolCalls` capability — so any existing MCP server keeps its previous
+synchronous behaviour bit-for-bit. Long-running tools (builds, deployments,
+batch jobs, sub-agent runs) get HTTP/SSE timeout-resistance and clean
+cancellation "for free" once both sides opt in.
+
+### Per-server mode
+
+```go
+import "time"
+
+host, _ := kit.New(ctx, &kit.Options{
+    MCPTaskMode: map[string]kit.MCPTaskMode{
+        "build-server": kit.MCPTaskModeAlways, // force task-augmented calls
+        "chat-server":  kit.MCPTaskModeNever,  // force synchronous calls
+        // any server not in the map honours its `tasksMode` config field
+        // (default "auto")
+    },
+})
+```
+
+| Mode | Behaviour |
+|---|---|
+| `MCPTaskModeAuto` (default) | Augment `tools/call` with `TaskParams` only when the server advertised `tasks/toolCalls`. |
+| `MCPTaskModeNever` | Always issue `tools/call` synchronously, ignoring server capability. |
+| `MCPTaskModeAlways` | Always opt in, even when the server didn't advertise the capability. The server may still respond synchronously. |
+
+### Progress callbacks
+
+```go
+host, _ := kit.New(ctx, &kit.Options{
+    MCPTaskTimeout:  15 * time.Minute,        // total wall-clock cap
+    MCPTaskTTL:      30 * time.Minute,        // server retention hint
+    MCPTaskProgress: func(p kit.MCPTaskProgress) {
+        log.Printf("%s/%s: %s %s", p.Server, p.TaskID, p.Status, p.Message)
+    },
+})
+```
+
+The handler fires once when a task is accepted and again on every observed
+status transition. The final call always carries a terminal status
+(`MCPTaskStatusCompleted`, `MCPTaskStatusFailed`, or `MCPTaskStatusCancelled`).
+Do not block in the handler — dispatch long work on a goroutine.
+
+### Inspecting and cancelling tasks
+
+```go
+tasks, _ := host.ListMCPTasks(ctx, "build-server")
+for _, t := range tasks {
+    fmt.Printf("%s: %s (%s)\n", t.TaskID, t.Status, t.StatusMessage)
+}
+
+t, _ := host.GetMCPTask(ctx, "build-server", taskID)
+if !t.Status.IsTerminal() {
+    _, _ = host.CancelMCPTask(ctx, "build-server", taskID)
+}
+```
+
+`Kit.ListMCPTasks`, `Kit.GetMCPTask`, and `Kit.CancelMCPTask` work against any
+loaded MCP server that advertises the corresponding capability.
+`MCPTaskStatus.IsTerminal()` is the canonical check for completion.
+
+Context cancellation also works end-to-end: cancelling the `ctx` passed to a
+tool execution triggers a best-effort `tasks/cancel` before the call returns.
+
 ## Precedence
 
 For any given generation or provider field, the effective value is resolved

www/pages/sdk/overview.md

@@ -201,6 +201,66 @@ host, _ := kit.New(ctx, &kit.Options{
 n, _ := host.AddInProcessMCPServer(ctx, "docs", mcpSrv)
 ```
 
+## Runtime skills and context files
+
+Kit auto-discovers skills and `AGENTS.md`-style context files during `New()`,
+but multi-tenant hosts (chatbots, web services, per-user agents) often need
+to swap these **after** construction. The runtime mutators below recompose
+the system prompt and apply it to the agent so the next turn picks up the
+updated instructions — no restart, no file shuffling.
+
+```go
+// Add a programmatic skill — no file on disk required.
+host.AddSkill(&kit.Skill{
+    Name:        "polite-french",
+    Description: "Respond in French and always greet the user.",
+    Content:     "Always reply in French. Open every response with 'Bonjour'.",
+})
+
+// Or load one from disk.
+host.LoadAndAddSkill("/var/skills/refund-policy.md")
+
+// Project context (AGENTS.md equivalents): inline content from a DB...
+host.AddContextFileContent(
+    fmt.Sprintf("session://%s/AGENTS.md", userID),
+    rulesFromDB,
+)
+// ...or load from disk.
+host.LoadAndAddContextFile("/etc/agents/tenant-acme.md")
+
+// Remove individually when a session ends.
+host.RemoveSkill("polite-french")
+host.RemoveContextFile(fmt.Sprintf("session://%s/AGENTS.md", userID))
+
+// Or replace the whole set in one call.
+host.SetSkills(activeSkillsForUser)
+host.SetContextFiles(activeContextForUser)
+
+// Inspect current state (snapshot copies — safe to mutate).
+skills := host.GetSkills()
+ctxFiles := host.GetContextFiles()
+```
+
+Key points:
+
+- **Auto-refresh.** Every `Add*` / `Remove*` / `Set*` call recomposes the system
+  prompt against the captured base prompt (preserving per-model overrides and
+  `--system-prompt` resolution) and pushes the result onto the agent. Call
+  `host.RefreshSystemPrompt()` only if you mutate state through a different
+  path and need to force a re-render.
+- **Dedup keys.** Skills dedupe by `Name`; context files dedupe by `Path`.
+  Re-adding the same key replaces the entry instead of appending a duplicate.
+- **Path is opaque.** `ContextFile.Path` does not have to point at a real file
+  — it's only used for dedup and for the `Instructions from: <Path>` header
+  injected into the prompt. URIs like `session://user-123/AGENTS.md` work fine.
+- **Thread safety.** All readers and mutators are safe to call concurrently
+  from multiple goroutines; the underlying state is guarded by an internal
+  `RWMutex`.
+- **Init-time options still apply.** `Options.Skills`, `Options.SkillsDir`,
+  `Options.NoSkills`, and `Options.NoContextFiles` continue to control the
+  startup set; the runtime API mutates from whatever state `New()` produced.
+  See [SDK options](/sdk/options#skills--configuration).
+
 ## MCP prompts and resources
 
 Query prompts and resources exposed by connected MCP servers:
@@ -215,6 +275,33 @@ resources := host.ListMCPResources()
 content, _ := host.ReadMCPResource(ctx, "server", "file:///path")
 ```
 
+## MCP tasks (long-running tools)
+
+Kit advertises [MCP task support](https://modelcontextprotocol.io/specification/2025-11-25/basic/utilities/tasks)
+during `initialize`, so cooperating servers can return a `taskId` immediately
+and let Kit poll `tasks/get` / `tasks/result` until the operation completes.
+This avoids HTTP/SSE proxy timeouts on long tools and gives you clean
+cancellation via context.
+
+```go
+host, _ := kit.New(ctx, &kit.Options{
+    MCPTaskMode: map[string]kit.MCPTaskMode{
+        "build-server": kit.MCPTaskModeAlways,
+    },
+    MCPTaskProgress: func(p kit.MCPTaskProgress) {
+        log.Printf("%s: %s", p.TaskID, p.Status)
+    },
+})
+
+// Inspect / cancel in-flight tasks
+tasks, _ := host.ListMCPTasks(ctx, "build-server")
+_, _    = host.CancelMCPTask(ctx, "build-server", tasks[0].TaskID)
+```
+
+Defaults to `MCPTaskModeAuto` per server, so any existing MCP server keeps
+its previous synchronous behaviour. See [SDK options → MCP Tasks](/sdk/options#mcp-tasks)
+for the full surface.
+
 ## Context and compaction
 
 Monitor and manage context usage:

www/public/session/index.html

@@ -1968,35 +1968,42 @@ a:hover { text-decoration: underline; }
 
   function renderEditBody(input, result) {
     let html = '';
-    const oldText = input.old_text || '';
-    const newText = input.new_text || '';
+    const edits = input.edits || [];
 
     html += '<div class="tool-input">';
     html += '<div class="tool-input-label">Changes</div>';
-    html += '<div class="diff-display">';
 
-    // Render old text lines as removed
-    if (oldText) {
-      const oldLines = oldText.split('\n');
-      for (const line of oldLines) {
-        html += `<div class="diff-line removed">- ${escapeHtml(line)}</div>`;
+    for (const edit of edits) {
+      const oldText = edit.old_text || '';
+      const newText = edit.new_text || '';
+
+      html += '<div class="diff-display">';
+
+      // Render old text lines as removed
+      if (oldText) {
+        const oldLines = oldText.split('\n');
+        for (const line of oldLines) {
+          html += `<div class="diff-line removed">- ${escapeHtml(line)}</div>`;
+        }
       }
-    }
 
-    // Separator
-    if (oldText && newText) {
-      html += '<div class="diff-separator">───</div>';
-    }
-
-    // Render new text lines as added
-    if (newText) {
-      const newLines = newText.split('\n');
-      for (const line of newLines) {
-        html += `<div class="diff-line added">+ ${escapeHtml(line)}</div>`;
+      // Separator
+      if (oldText && newText) {
+        html += '<div class="diff-separator">───</div>';
       }
+
+      // Render new text lines as added
+      if (newText) {
+        const newLines = newText.split('\n');
+        for (const line of newLines) {
+          html += `<div class="diff-line added">+ ${escapeHtml(line)}</div>`;
+        }
+      }
+
+      html += '</div>';
     }
 
-    html += '</div></div>';
+    html += '</div>';
 
     if (result && result.is_error) {
       html += renderToolOutput(result.content, true);