refactor: remove fantasy dependency name leaks from SDK surface

- Rename ExtensionToolsAsFantasy -> ExtensionToolsAsLLMTools
- Rename convertKitMessagesToFantasy -> convertToLLMMessages
- Delete GetFantasyProviders, ToFantasyMessages, FromFantasyMessage
- Replace direct fantasy type usage with kit.LLM* aliases in app tests
- Scrub fantasy references from godoc comments across pkg/kit and internal

internal/app/messages_test.go

@@ -3,24 +3,21 @@ package app
 import (
 	"testing"
 
-	"charm.land/fantasy"
-
 	kit "github.com/mark3labs/kit/pkg/kit"
 )
 
-// makeTextMsg builds a minimal kit.LLMMessage using fantasy.NewUserMessage
-// or constructing with the given role.
+// makeTextMsg builds a minimal kit.LLMMessage with the given role and text.
 func makeTextMsg(role, text string) kit.LLMMessage {
 	return kit.LLMMessage{
 		Role:    kit.LLMMessageRole(role),
-		Content: []fantasy.MessagePart{fantasy.TextPart{Text: text}},
+		Content: []kit.LLMMessagePart{kit.LLMTextPart{Text: text}},
 	}
 }
 
 // textOf extracts the plain text from an LLMMessage for assertions.
 func textOf(msg kit.LLMMessage) string {
 	for _, part := range msg.Content {
-		if tp, ok := part.(fantasy.TextPart); ok {
+		if tp, ok := part.(kit.LLMTextPart); ok {
 			return tp.Text
 		}
 	}

internal/extensions/api.go

@@ -918,7 +918,7 @@ type ExtensionEntry struct {
 type ContextMessage struct {
 	// Index is the position of this message in the original context array
 	// (0-based). When returning messages from a ContextPrepareResult,
-	// messages with Index >= 0 reuse the original fantasy.Message at that
+	// messages with Index >= 0 reuse the original LLM message at that
 	// position (preserving tool calls, reasoning, and other complex parts).
 	// Set Index to -1 for newly injected messages (created from Role + Content).
 	Index int

internal/extensions/wrapper.go

@@ -28,11 +28,11 @@ func WrapToolsWithExtensions(tools []fantasy.AgentTool, runner *Runner) []fantas
 	return wrapped
 }
 
-// ExtensionToolsAsFantasy converts ToolDef values registered by extensions
-// into fantasy.AgentTool implementations so the LLM can invoke them.
+// ExtensionToolsAsLLMTools converts ToolDef values registered by extensions
+// into LLM agent tool implementations so the LLM can invoke them.
 // The runner is optional; if provided, ToolContext.OnProgress routes
 // progress messages through the runner's Print function.
-func ExtensionToolsAsFantasy(defs []ToolDef, runner *Runner) []fantasy.AgentTool {
+func ExtensionToolsAsLLMTools(defs []ToolDef, runner *Runner) []fantasy.AgentTool {
 	tools := make([]fantasy.AgentTool, 0, len(defs))
 	for _, def := range defs {
 		tools = append(tools, &extensionTool{def: def, runner: runner})
@@ -154,7 +154,7 @@ func (w *wrappedTool) Run(ctx context.Context, call fantasy.ToolCall) (fantasy.T
 }
 
 // ---------------------------------------------------------------------------
-// extensionTool — wraps a ToolDef into a fantasy.AgentTool
+// extensionTool — wraps a ToolDef into an LLM agent tool
 // ---------------------------------------------------------------------------
 
 type extensionTool struct {
@@ -182,7 +182,7 @@ func (t *extensionTool) Info() fantasy.ToolInfo {
 				info.Parameters = props
 			} else {
 				// Schema doesn't have "properties" — use as-is (may be
-				// a flat property map already matching fantasy's format).
+				// a flat property map already matching the expected format).
 				info.Parameters = schema
 			}
 			// Extract required fields if present.

internal/extensions/wrapper_test.go

@@ -192,7 +192,7 @@ func TestWrappedTool_ExecutionStartEnd(t *testing.T) {
 	}
 }
 
-func TestExtensionToolsAsFantasy(t *testing.T) {
+func TestExtensionToolsAsLLMTools(t *testing.T) {
 	defs := []ToolDef{
 		{
 			Name:        "greet",
@@ -202,7 +202,7 @@ func TestExtensionToolsAsFantasy(t *testing.T) {
 		},
 	}
 
-	tools := ExtensionToolsAsFantasy(defs, nil)
+	tools := ExtensionToolsAsLLMTools(defs, nil)
 	if len(tools) != 1 {
 		t.Fatalf("expected 1 tool, got %d", len(tools))
 	}
@@ -232,7 +232,7 @@ func TestExtensionTool_Error(t *testing.T) {
 		},
 	}
 
-	tools := ExtensionToolsAsFantasy(defs, nil)
+	tools := ExtensionToolsAsLLMTools(defs, nil)
 	resp, err := tools[0].Run(context.Background(), fantasy.ToolCall{Input: "x"})
 	if err == nil {
 		t.Error("expected error")
@@ -259,7 +259,7 @@ func TestExtensionTool_ExecuteWithContext(t *testing.T) {
 	}
 
 	// Without runner, OnProgress is a no-op.
-	tools := ExtensionToolsAsFantasy(defs, nil)
+	tools := ExtensionToolsAsLLMTools(defs, nil)
 	resp, err := tools[0].Run(context.Background(), fantasy.ToolCall{Input: "test"})
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
@@ -285,7 +285,7 @@ func TestExtensionTool_ExecuteWithContext(t *testing.T) {
 			},
 		},
 	}
-	tools2 := ExtensionToolsAsFantasy(defs2, runner)
+	tools2 := ExtensionToolsAsLLMTools(defs2, runner)
 	_, err = tools2[0].Run(context.Background(), fantasy.ToolCall{Input: ""})
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
@@ -306,7 +306,7 @@ func TestExtensionTool_ExecuteWithContextPriority(t *testing.T) {
 			},
 		},
 	}
-	tools := ExtensionToolsAsFantasy(defs, nil)
+	tools := ExtensionToolsAsLLMTools(defs, nil)
 	resp, err := tools[0].Run(context.Background(), fantasy.ToolCall{Input: ""})
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
@@ -330,7 +330,7 @@ func TestExtensionTool_CancelledContext(t *testing.T) {
 			},
 		},
 	}
-	tools := ExtensionToolsAsFantasy(defs, nil)
+	tools := ExtensionToolsAsLLMTools(defs, nil)
 	_, _ = tools[0].Run(ctx, fantasy.ToolCall{Input: ""})
 	if !sawCancelled {
 		t.Error("expected IsCancelled=true for cancelled context")
@@ -339,7 +339,7 @@ func TestExtensionTool_CancelledContext(t *testing.T) {
 
 func TestExtensionTool_ProviderOptions(t *testing.T) {
 	defs := []ToolDef{{Name: "test", Execute: func(string) (string, error) { return "", nil }}}
-	tools := ExtensionToolsAsFantasy(defs, nil)
+	tools := ExtensionToolsAsLLMTools(defs, nil)
 
 	// Initially nil.
 	opts := tools[0].ProviderOptions()

internal/kitsetup/setup.go

@@ -267,7 +267,7 @@ func loadExtensions() (*extensions.Runner, extensionCreationOpts, error) {
 		return extensions.WrapToolsWithExtensions(tools, runner)
 	}
 
-	extTools := extensions.ExtensionToolsAsFantasy(runner.RegisteredTools(), runner)
+	extTools := extensions.ExtensionToolsAsLLMTools(runner.RegisteredTools(), runner)
 
 	return runner, extensionCreationOpts{
 		toolWrapper: wrapper,

internal/message/content.go

@@ -325,12 +325,6 @@ func UnmarshalParts(data []byte) ([]ContentPart, error) {
 // mixed TextPart and ToolCallPart content. Tool-role messages produce
 // ToolResultPart entries.
 func (m *Message) ToLLMMessages() []fantasy.Message {
-	return m.ToFantasyMessages()
-}
-
-// Deprecated: Use ToLLMMessages instead.
-// ToFantasyMessages converts a Message to one or more LLM message values.
-func (m *Message) ToFantasyMessages() []fantasy.Message {
 	switch m.Role {
 	case RoleAssistant:
 		var parts []fantasy.MessagePart
@@ -431,13 +425,6 @@ func (m *Message) ToFantasyMessages() []fantasy.Message {
 // FromLLMMessage converts an LLM message into our Message type,
 // extracting all content parts into the appropriate block types.
 func FromLLMMessage(msg fantasy.Message) Message {
-	return FromFantasyMessage(msg)
-}
-
-// Deprecated: Use FromLLMMessage instead.
-// FromFantasyMessage converts an LLM message into our Message type,
-// extracting all content parts into the appropriate block types.
-func FromFantasyMessage(msg fantasy.Message) Message {
 	m := Message{
 		Role:      MessageRole(msg.Role),
 		Parts:     make([]ContentPart, 0),

internal/models/registry.go

@@ -379,11 +379,6 @@ func (r *ModelsRegistry) GetLLMProviders() []string {
 	return providers
 }
 
-// Deprecated: Use GetLLMProviders instead.
-func (r *ModelsRegistry) GetFantasyProviders() []string {
-	return r.GetLLMProviders()
-}
-
 // isProviderLLMSupported checks if a provider can be used with the LLM layer.
 func isProviderLLMSupported(providerID string, info *ProviderInfo) bool {
 	// Ollama and custom are always supported (model names are user-defined).

pkg/kit/adapter.go

@@ -22,13 +22,13 @@ func NewTreeManagerAdapter(tm *session.TreeManager) SessionManager {
 
 // AppendMessage implements SessionManager.
 func (a *treeManagerAdapter) AppendMessage(msg LLMMessage) (string, error) {
-	// LLMMessage is just an alias for fantasy.Message, so no conversion needed
+	// LLMMessage is a type alias, so no conversion needed.
 	return a.inner.AppendLLMMessage(msg)
 }
 
 // GetMessages implements SessionManager.
 func (a *treeManagerAdapter) GetMessages() []LLMMessage {
-	// LLMMessage is just an alias for fantasy.Message
+	// LLMMessage is a type alias, so no conversion needed.
 	return a.inner.GetLLMMessages()
 }
 
@@ -223,9 +223,8 @@ func (a *treeManagerAdapter) convertEntry(entry any) *BranchEntry {
 	}
 }
 
-// convertKitMessagesToFantasy converts kit LLM messages to fantasy messages.
-// Since LLMMessage is an alias for fantasy.Message, this is a no-op.
-func convertKitMessagesToFantasy(msgs []LLMMessage) []fantasy.Message {
-	// LLMMessage is just an alias for fantasy.Message, so we can type convert
+// convertToLLMMessages converts kit LLM messages to the underlying provider
+// message type. Since LLMMessage is a type alias, this is a no-op.
+func convertToLLMMessages(msgs []LLMMessage) []fantasy.Message {
 	return msgs
 }

pkg/kit/compaction.go

@@ -58,7 +58,7 @@ func (m *Kit) ShouldCompact() bool {
 
 	// Fall back to text-based heuristic before first turn completes.
 	messages := m.session.GetMessages()
-	return compaction.ShouldCompact(convertKitMessagesToFantasy(messages), info.Limit.Context, reserveTokens)
+	return compaction.ShouldCompact(convertToLLMMessages(messages), info.Limit.Context, reserveTokens)
 }
 
 // GetContextStats returns current context usage statistics including
@@ -203,9 +203,9 @@ func (m *Kit) compactInternal(ctx context.Context, opts *CompactionOptions, cust
 // custom summary. It still determines the cut point and persists a
 // CompactionEntry.
 func (m *Kit) applyCustomCompaction(summary string, messages []LLMMessage, opts *CompactionOptions) (*CompactionResult, error) {
-	originalTokens := compaction.EstimateMessageTokens(convertKitMessagesToFantasy(messages))
+	originalTokens := compaction.EstimateMessageTokens(convertToLLMMessages(messages))
 
-	cutPoint := compaction.FindCutPoint(convertKitMessagesToFantasy(messages), opts.KeepRecentTokens)
+	cutPoint := compaction.FindCutPoint(convertToLLMMessages(messages), opts.KeepRecentTokens)
 	if cutPoint == 0 {
 		cutPoint = len(messages) - 1
 		if cutPoint < 1 {

pkg/kit/kit.go

@@ -562,7 +562,7 @@ func (m *Kit) ReloadExtensions() error {
 
 	// Update extension tools on the agent so the LLM sees changes.
 	if m.agent != nil {
-		extTools := extensions.ExtensionToolsAsFantasy(m.extRunner.RegisteredTools(), m.extRunner)
+		extTools := extensions.ExtensionToolsAsLLMTools(m.extRunner.RegisteredTools(), m.extRunner)
 		m.agent.SetExtraTools(extTools)
 	}
 

pkg/kit/models.go

@@ -22,11 +22,6 @@ func GetLLMProviders() []string {
 	return models.GetGlobalRegistry().GetLLMProviders()
 }
 
-// Deprecated: Use GetLLMProviders instead.
-func GetFantasyProviders() []string {
-	return GetLLMProviders()
-}
-
 // GetModelsForProvider returns all known models for a provider.
 func GetModelsForProvider(provider string) (map[string]ModelInfo, error) {
 	return models.GetGlobalRegistry().GetModelsForProvider(provider)

pkg/kit/types.go

@@ -129,9 +129,9 @@ type SpinnerFunc = agent.SpinnerFunc
 
 // ==== LLM Types ====
 //
-// These are type aliases for the corresponding charm.land/fantasy types,
-// giving them clean LLM-prefixed names without leaking the dependency name.
-// SDK consumers can use these types without importing charm.land/fantasy directly.
+// These are type aliases for the underlying LLM provider types, giving them
+// clean LLM-prefixed names without leaking the dependency name. SDK consumers
+// can use these types without importing the provider package directly.
 
 // LLMMessage represents a message in an LLM conversation, carrying a role
 // and a slice of typed content parts (text, tool calls, reasoning, etc.).
@@ -177,7 +177,7 @@ type LLMMessageRole = fantasy.MessageRole
 // LLMFinishReason indicates why the LLM stopped generating.
 type LLMFinishReason = fantasy.FinishReason
 
-// LLM role constants mirror fantasy.MessageRole* values under clean LLM-prefixed names.
+// LLM role constants mirror the provider's role values under clean LLM-prefixed names.
 const (
 	// LLMRoleUser identifies a user message.
 	LLMRoleUser = fantasy.MessageRoleUser
@@ -190,11 +190,11 @@ const (
 )
 
 // NewLLMUserMessage constructs a user-role LLMMessage with optional file
-// attachments. It is equivalent to fantasy.NewUserMessage.
+// attachments.
 var NewLLMUserMessage = fantasy.NewUserMessage
 
 // NewLLMSystemMessage constructs a system-role LLMMessage from one or more
-// prompt strings. It is equivalent to fantasy.NewSystemMessage.
+// prompt strings.
 var NewLLMSystemMessage = fantasy.NewSystemMessage
 
 // ==== Compaction Types (internal/compaction/) ====

pkg/kit/types_test.go

@@ -77,8 +77,8 @@ func TestLLMRoleConstants(t *testing.T) {
 	}
 }
 
-// TestLLMMessageAlias verifies LLMMessage is a type alias for fantasy.Message
-// and can be used interchangeably.
+// TestLLMMessageAlias verifies LLMMessage is a type alias for the underlying
+// LLM provider message type and can be used interchangeably.
 func TestLLMMessageAlias(t *testing.T) {
 	// Construct an LLMMessage using alias types.
 	msg := kit.LLMMessage{
@@ -132,8 +132,8 @@ func TestNewLLMSystemMessage(t *testing.T) {
 	}
 }
 
-// TestLLMUsageAlias verifies LLMUsage is a type alias for fantasy.Usage
-// and carries the correct fields.
+// TestLLMUsageAlias verifies LLMUsage is a type alias for the underlying
+// LLM provider usage type and carries the correct fields.
 func TestLLMUsageAlias(t *testing.T) {
 	u := kit.LLMUsage{
 		InputTokens:         100,
@@ -150,7 +150,7 @@ func TestLLMUsageAlias(t *testing.T) {
 		t.Errorf("LLMUsage.TotalTokens = %d, want 150", u.TotalTokens)
 	}
 
-	// Verify JSON marshaling uses snake_case (inherited from fantasy.Usage tags).
+	// Verify JSON marshaling uses snake_case (inherited from the provider's tags).
 	data, err := json.Marshal(u)
 	if err != nil {
 		t.Fatalf("LLMUsage.MarshalJSON: %v", err)
@@ -165,7 +165,8 @@ func TestLLMUsageAlias(t *testing.T) {
 	}
 }
 
-// TestLLMFilePartAlias verifies LLMFilePart is a type alias for fantasy.FilePart.
+// TestLLMFilePartAlias verifies LLMFilePart is a type alias for the underlying
+// LLM provider file part type.
 func TestLLMFilePartAlias(t *testing.T) {
 	fp := kit.LLMFilePart{
 		Filename:  "screenshot.png",