refactor(providers): move anthropic logic to protocol package

pkg/providers/anthropic/provider.go

@@ -0,0 +1,241 @@
+package anthropicprovider
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+
+	"github.com/anthropics/anthropic-sdk-go"
+	"github.com/anthropics/anthropic-sdk-go/option"
+)
+
+type ToolCall struct {
+	ID        string                 `json:"id"`
+	Type      string                 `json:"type,omitempty"`
+	Function  *FunctionCall          `json:"function,omitempty"`
+	Name      string                 `json:"name,omitempty"`
+	Arguments map[string]interface{} `json:"arguments,omitempty"`
+}
+
+type FunctionCall struct {
+	Name      string `json:"name"`
+	Arguments string `json:"arguments"`
+}
+
+type LLMResponse struct {
+	Content      string     `json:"content"`
+	ToolCalls    []ToolCall `json:"tool_calls,omitempty"`
+	FinishReason string     `json:"finish_reason"`
+	Usage        *UsageInfo `json:"usage,omitempty"`
+}
+
+type UsageInfo struct {
+	PromptTokens     int `json:"prompt_tokens"`
+	CompletionTokens int `json:"completion_tokens"`
+	TotalTokens      int `json:"total_tokens"`
+}
+
+type Message struct {
+	Role       string     `json:"role"`
+	Content    string     `json:"content"`
+	ToolCalls  []ToolCall `json:"tool_calls,omitempty"`
+	ToolCallID string     `json:"tool_call_id,omitempty"`
+}
+
+type ToolDefinition struct {
+	Type     string                 `json:"type"`
+	Function ToolFunctionDefinition `json:"function"`
+}
+
+type ToolFunctionDefinition struct {
+	Name        string                 `json:"name"`
+	Description string                 `json:"description"`
+	Parameters  map[string]interface{} `json:"parameters"`
+}
+
+type Provider struct {
+	client      *anthropic.Client
+	tokenSource func() (string, error)
+}
+
+func NewProvider(token string) *Provider {
+	client := anthropic.NewClient(
+		option.WithAuthToken(token),
+		option.WithBaseURL("https://api.anthropic.com"),
+	)
+	return &Provider{client: &client}
+}
+
+func NewProviderWithClient(client *anthropic.Client) *Provider {
+	return &Provider{client: client}
+}
+
+func NewProviderWithTokenSource(token string, tokenSource func() (string, error)) *Provider {
+	p := NewProvider(token)
+	p.tokenSource = tokenSource
+	return p
+}
+
+func (p *Provider) Chat(ctx context.Context, messages []Message, tools []ToolDefinition, model string, options map[string]interface{}) (*LLMResponse, error) {
+	var opts []option.RequestOption
+	if p.tokenSource != nil {
+		tok, err := p.tokenSource()
+		if err != nil {
+			return nil, fmt.Errorf("refreshing token: %w", err)
+		}
+		opts = append(opts, option.WithAuthToken(tok))
+	}
+
+	params, err := buildParams(messages, tools, model, options)
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err := p.client.Messages.New(ctx, params, opts...)
+	if err != nil {
+		return nil, fmt.Errorf("claude API call: %w", err)
+	}
+
+	return parseResponse(resp), nil
+}
+
+func (p *Provider) GetDefaultModel() string {
+	return "claude-sonnet-4-5-20250929"
+}
+
+func buildParams(messages []Message, tools []ToolDefinition, model string, options map[string]interface{}) (anthropic.MessageNewParams, error) {
+	var system []anthropic.TextBlockParam
+	var anthropicMessages []anthropic.MessageParam
+
+	for _, msg := range messages {
+		switch msg.Role {
+		case "system":
+			system = append(system, anthropic.TextBlockParam{Text: msg.Content})
+		case "user":
+			if msg.ToolCallID != "" {
+				anthropicMessages = append(anthropicMessages,
+					anthropic.NewUserMessage(anthropic.NewToolResultBlock(msg.ToolCallID, msg.Content, false)),
+				)
+			} else {
+				anthropicMessages = append(anthropicMessages,
+					anthropic.NewUserMessage(anthropic.NewTextBlock(msg.Content)),
+				)
+			}
+		case "assistant":
+			if len(msg.ToolCalls) > 0 {
+				var blocks []anthropic.ContentBlockParamUnion
+				if msg.Content != "" {
+					blocks = append(blocks, anthropic.NewTextBlock(msg.Content))
+				}
+				for _, tc := range msg.ToolCalls {
+					blocks = append(blocks, anthropic.NewToolUseBlock(tc.ID, tc.Arguments, tc.Name))
+				}
+				anthropicMessages = append(anthropicMessages, anthropic.NewAssistantMessage(blocks...))
+			} else {
+				anthropicMessages = append(anthropicMessages,
+					anthropic.NewAssistantMessage(anthropic.NewTextBlock(msg.Content)),
+				)
+			}
+		case "tool":
+			anthropicMessages = append(anthropicMessages,
+				anthropic.NewUserMessage(anthropic.NewToolResultBlock(msg.ToolCallID, msg.Content, false)),
+			)
+		}
+	}
+
+	maxTokens := int64(4096)
+	if mt, ok := options["max_tokens"].(int); ok {
+		maxTokens = int64(mt)
+	}
+
+	params := anthropic.MessageNewParams{
+		Model:     anthropic.Model(model),
+		Messages:  anthropicMessages,
+		MaxTokens: maxTokens,
+	}
+
+	if len(system) > 0 {
+		params.System = system
+	}
+
+	if temp, ok := options["temperature"].(float64); ok {
+		params.Temperature = anthropic.Float(temp)
+	}
+
+	if len(tools) > 0 {
+		params.Tools = translateTools(tools)
+	}
+
+	return params, nil
+}
+
+func translateTools(tools []ToolDefinition) []anthropic.ToolUnionParam {
+	result := make([]anthropic.ToolUnionParam, 0, len(tools))
+	for _, t := range tools {
+		tool := anthropic.ToolParam{
+			Name: t.Function.Name,
+			InputSchema: anthropic.ToolInputSchemaParam{
+				Properties: t.Function.Parameters["properties"],
+			},
+		}
+		if desc := t.Function.Description; desc != "" {
+			tool.Description = anthropic.String(desc)
+		}
+		if req, ok := t.Function.Parameters["required"].([]interface{}); ok {
+			required := make([]string, 0, len(req))
+			for _, r := range req {
+				if s, ok := r.(string); ok {
+					required = append(required, s)
+				}
+			}
+			tool.InputSchema.Required = required
+		}
+		result = append(result, anthropic.ToolUnionParam{OfTool: &tool})
+	}
+	return result
+}
+
+func parseResponse(resp *anthropic.Message) *LLMResponse {
+	var content string
+	var toolCalls []ToolCall
+
+	for _, block := range resp.Content {
+		switch block.Type {
+		case "text":
+			tb := block.AsText()
+			content += tb.Text
+		case "tool_use":
+			tu := block.AsToolUse()
+			var args map[string]interface{}
+			if err := json.Unmarshal(tu.Input, &args); err != nil {
+				args = map[string]interface{}{"raw": string(tu.Input)}
+			}
+			toolCalls = append(toolCalls, ToolCall{
+				ID:        tu.ID,
+				Name:      tu.Name,
+				Arguments: args,
+			})
+		}
+	}
+
+	finishReason := "stop"
+	switch resp.StopReason {
+	case anthropic.StopReasonToolUse:
+		finishReason = "tool_calls"
+	case anthropic.StopReasonMaxTokens:
+		finishReason = "length"
+	case anthropic.StopReasonEndTurn:
+		finishReason = "stop"
+	}
+
+	return &LLMResponse{
+		Content:      content,
+		ToolCalls:    toolCalls,
+		FinishReason: finishReason,
+		Usage: &UsageInfo{
+			PromptTokens:     int(resp.Usage.InputTokens),
+			CompletionTokens: int(resp.Usage.OutputTokens),
+			TotalTokens:      int(resp.Usage.InputTokens + resp.Usage.OutputTokens),
+		},
+	}
+}

pkg/providers/anthropic/provider_test.go

@@ -0,0 +1,208 @@
+package anthropicprovider
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/anthropics/anthropic-sdk-go"
+	anthropicoption "github.com/anthropics/anthropic-sdk-go/option"
+)
+
+func TestBuildParams_BasicMessage(t *testing.T) {
+	messages := []Message{
+		{Role: "user", Content: "Hello"},
+	}
+	params, err := buildParams(messages, nil, "claude-sonnet-4-5-20250929", map[string]interface{}{
+		"max_tokens": 1024,
+	})
+	if err != nil {
+		t.Fatalf("buildParams() error: %v", err)
+	}
+	if string(params.Model) != "claude-sonnet-4-5-20250929" {
+		t.Errorf("Model = %q, want %q", params.Model, "claude-sonnet-4-5-20250929")
+	}
+	if params.MaxTokens != 1024 {
+		t.Errorf("MaxTokens = %d, want 1024", params.MaxTokens)
+	}
+	if len(params.Messages) != 1 {
+		t.Fatalf("len(Messages) = %d, want 1", len(params.Messages))
+	}
+}
+
+func TestBuildParams_SystemMessage(t *testing.T) {
+	messages := []Message{
+		{Role: "system", Content: "You are helpful"},
+		{Role: "user", Content: "Hi"},
+	}
+	params, err := buildParams(messages, nil, "claude-sonnet-4-5-20250929", map[string]interface{}{})
+	if err != nil {
+		t.Fatalf("buildParams() error: %v", err)
+	}
+	if len(params.System) != 1 {
+		t.Fatalf("len(System) = %d, want 1", len(params.System))
+	}
+	if params.System[0].Text != "You are helpful" {
+		t.Errorf("System[0].Text = %q, want %q", params.System[0].Text, "You are helpful")
+	}
+	if len(params.Messages) != 1 {
+		t.Fatalf("len(Messages) = %d, want 1", len(params.Messages))
+	}
+}
+
+func TestBuildParams_ToolCallMessage(t *testing.T) {
+	messages := []Message{
+		{Role: "user", Content: "What's the weather?"},
+		{
+			Role:    "assistant",
+			Content: "",
+			ToolCalls: []ToolCall{
+				{
+					ID:        "call_1",
+					Name:      "get_weather",
+					Arguments: map[string]interface{}{"city": "SF"},
+				},
+			},
+		},
+		{Role: "tool", Content: `{"temp": 72}`, ToolCallID: "call_1"},
+	}
+	params, err := buildParams(messages, nil, "claude-sonnet-4-5-20250929", map[string]interface{}{})
+	if err != nil {
+		t.Fatalf("buildParams() error: %v", err)
+	}
+	if len(params.Messages) != 3 {
+		t.Fatalf("len(Messages) = %d, want 3", len(params.Messages))
+	}
+}
+
+func TestBuildParams_WithTools(t *testing.T) {
+	tools := []ToolDefinition{
+		{
+			Type: "function",
+			Function: ToolFunctionDefinition{
+				Name:        "get_weather",
+				Description: "Get weather for a city",
+				Parameters: map[string]interface{}{
+					"type": "object",
+					"properties": map[string]interface{}{
+						"city": map[string]interface{}{"type": "string"},
+					},
+					"required": []interface{}{"city"},
+				},
+			},
+		},
+	}
+	params, err := buildParams([]Message{{Role: "user", Content: "Hi"}}, tools, "claude-sonnet-4-5-20250929", map[string]interface{}{})
+	if err != nil {
+		t.Fatalf("buildParams() error: %v", err)
+	}
+	if len(params.Tools) != 1 {
+		t.Fatalf("len(Tools) = %d, want 1", len(params.Tools))
+	}
+}
+
+func TestParseResponse_TextOnly(t *testing.T) {
+	resp := &anthropic.Message{
+		Content: []anthropic.ContentBlockUnion{},
+		Usage: anthropic.Usage{
+			InputTokens:  10,
+			OutputTokens: 20,
+		},
+	}
+	result := parseResponse(resp)
+	if result.Usage.PromptTokens != 10 {
+		t.Errorf("PromptTokens = %d, want 10", result.Usage.PromptTokens)
+	}
+	if result.Usage.CompletionTokens != 20 {
+		t.Errorf("CompletionTokens = %d, want 20", result.Usage.CompletionTokens)
+	}
+	if result.FinishReason != "stop" {
+		t.Errorf("FinishReason = %q, want %q", result.FinishReason, "stop")
+	}
+}
+
+func TestParseResponse_StopReasons(t *testing.T) {
+	tests := []struct {
+		stopReason anthropic.StopReason
+		want       string
+	}{
+		{anthropic.StopReasonEndTurn, "stop"},
+		{anthropic.StopReasonMaxTokens, "length"},
+		{anthropic.StopReasonToolUse, "tool_calls"},
+	}
+	for _, tt := range tests {
+		resp := &anthropic.Message{
+			StopReason: tt.stopReason,
+		}
+		result := parseResponse(resp)
+		if result.FinishReason != tt.want {
+			t.Errorf("StopReason %q: FinishReason = %q, want %q", tt.stopReason, result.FinishReason, tt.want)
+		}
+	}
+}
+
+func TestProvider_ChatRoundTrip(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path != "/v1/messages" {
+			http.Error(w, "not found", http.StatusNotFound)
+			return
+		}
+		if r.Header.Get("Authorization") != "Bearer test-token" {
+			http.Error(w, "unauthorized", http.StatusUnauthorized)
+			return
+		}
+
+		var reqBody map[string]interface{}
+		json.NewDecoder(r.Body).Decode(&reqBody)
+
+		resp := map[string]interface{}{
+			"id":          "msg_test",
+			"type":        "message",
+			"role":        "assistant",
+			"model":       reqBody["model"],
+			"stop_reason": "end_turn",
+			"content": []map[string]interface{}{
+				{"type": "text", "text": "Hello! How can I help you?"},
+			},
+			"usage": map[string]interface{}{
+				"input_tokens":  15,
+				"output_tokens": 8,
+			},
+		}
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(resp)
+	}))
+	defer server.Close()
+
+	provider := NewProviderWithClient(createAnthropicTestClient(server.URL, "test-token"))
+	messages := []Message{{Role: "user", Content: "Hello"}}
+	resp, err := provider.Chat(t.Context(), messages, nil, "claude-sonnet-4-5-20250929", map[string]interface{}{"max_tokens": 1024})
+	if err != nil {
+		t.Fatalf("Chat() error: %v", err)
+	}
+	if resp.Content != "Hello! How can I help you?" {
+		t.Errorf("Content = %q, want %q", resp.Content, "Hello! How can I help you?")
+	}
+	if resp.FinishReason != "stop" {
+		t.Errorf("FinishReason = %q, want %q", resp.FinishReason, "stop")
+	}
+	if resp.Usage.PromptTokens != 15 {
+		t.Errorf("PromptTokens = %d, want 15", resp.Usage.PromptTokens)
+	}
+}
+
+func TestProvider_GetDefaultModel(t *testing.T) {
+	p := NewProvider("test-token")
+	if got := p.GetDefaultModel(); got != "claude-sonnet-4-5-20250929" {
+		t.Errorf("GetDefaultModel() = %q, want %q", got, "claude-sonnet-4-5-20250929")
+	}
+}
+
+func createAnthropicTestClient(baseURL, token string) *anthropic.Client {
+	c := anthropic.NewClient(
+		anthropicoption.WithAuthToken(token),
+		anthropicoption.WithBaseURL(baseURL),
+	)
+	return &c
+}

pkg/providers/claude_provider.go

@@ -2,195 +2,48 @@ package providers
 
 import (
 	"context"
-	"encoding/json"
 	"fmt"
 
-	"github.com/anthropics/anthropic-sdk-go"
-	"github.com/anthropics/anthropic-sdk-go/option"
 	"github.com/sipeed/picoclaw/pkg/auth"
+	anthropicprovider "github.com/sipeed/picoclaw/pkg/providers/anthropic"
 )
 
 type ClaudeProvider struct {
-	client      *anthropic.Client
-	tokenSource func() (string, error)
+	delegate *anthropicprovider.Provider
 }
 
 func NewClaudeProvider(token string) *ClaudeProvider {
-	client := anthropic.NewClient(
-		option.WithAuthToken(token),
-		option.WithBaseURL("https://api.anthropic.com"),
-	)
-	return &ClaudeProvider{client: &client}
+	return &ClaudeProvider{
+		delegate: anthropicprovider.NewProvider(token),
+	}
 }
 
 func NewClaudeProviderWithTokenSource(token string, tokenSource func() (string, error)) *ClaudeProvider {
-	p := NewClaudeProvider(token)
-	p.tokenSource = tokenSource
-	return p
+	return &ClaudeProvider{
+		delegate: anthropicprovider.NewProviderWithTokenSource(token, tokenSource),
+	}
+}
+
+func newClaudeProviderWithDelegate(delegate *anthropicprovider.Provider) *ClaudeProvider {
+	return &ClaudeProvider{delegate: delegate}
 }
 
 func (p *ClaudeProvider) Chat(ctx context.Context, messages []Message, tools []ToolDefinition, model string, options map[string]interface{}) (*LLMResponse, error) {
-	var opts []option.RequestOption
-	if p.tokenSource != nil {
-		tok, err := p.tokenSource()
-		if err != nil {
-			return nil, fmt.Errorf("refreshing token: %w", err)
-		}
-		opts = append(opts, option.WithAuthToken(tok))
-	}
-
-	params, err := buildClaudeParams(messages, tools, model, options)
+	resp, err := p.delegate.Chat(
+		ctx,
+		toAnthropicProviderMessages(messages),
+		toAnthropicProviderTools(tools),
+		model,
+		options,
+	)
 	if err != nil {
 		return nil, err
 	}
-
-	resp, err := p.client.Messages.New(ctx, params, opts...)
-	if err != nil {
-		return nil, fmt.Errorf("claude API call: %w", err)
-	}
-
-	return parseClaudeResponse(resp), nil
+	return fromAnthropicProviderResponse(resp), nil
 }
 
 func (p *ClaudeProvider) GetDefaultModel() string {
-	return "claude-sonnet-4-5-20250929"
-}
-
-func buildClaudeParams(messages []Message, tools []ToolDefinition, model string, options map[string]interface{}) (anthropic.MessageNewParams, error) {
-	var system []anthropic.TextBlockParam
-	var anthropicMessages []anthropic.MessageParam
-
-	for _, msg := range messages {
-		switch msg.Role {
-		case "system":
-			system = append(system, anthropic.TextBlockParam{Text: msg.Content})
-		case "user":
-			if msg.ToolCallID != "" {
-				anthropicMessages = append(anthropicMessages,
-					anthropic.NewUserMessage(anthropic.NewToolResultBlock(msg.ToolCallID, msg.Content, false)),
-				)
-			} else {
-				anthropicMessages = append(anthropicMessages,
-					anthropic.NewUserMessage(anthropic.NewTextBlock(msg.Content)),
-				)
-			}
-		case "assistant":
-			if len(msg.ToolCalls) > 0 {
-				var blocks []anthropic.ContentBlockParamUnion
-				if msg.Content != "" {
-					blocks = append(blocks, anthropic.NewTextBlock(msg.Content))
-				}
-				for _, tc := range msg.ToolCalls {
-					blocks = append(blocks, anthropic.NewToolUseBlock(tc.ID, tc.Arguments, tc.Name))
-				}
-				anthropicMessages = append(anthropicMessages, anthropic.NewAssistantMessage(blocks...))
-			} else {
-				anthropicMessages = append(anthropicMessages,
-					anthropic.NewAssistantMessage(anthropic.NewTextBlock(msg.Content)),
-				)
-			}
-		case "tool":
-			anthropicMessages = append(anthropicMessages,
-				anthropic.NewUserMessage(anthropic.NewToolResultBlock(msg.ToolCallID, msg.Content, false)),
-			)
-		}
-	}
-
-	maxTokens := int64(4096)
-	if mt, ok := options["max_tokens"].(int); ok {
-		maxTokens = int64(mt)
-	}
-
-	params := anthropic.MessageNewParams{
-		Model:     anthropic.Model(model),
-		Messages:  anthropicMessages,
-		MaxTokens: maxTokens,
-	}
-
-	if len(system) > 0 {
-		params.System = system
-	}
-
-	if temp, ok := options["temperature"].(float64); ok {
-		params.Temperature = anthropic.Float(temp)
-	}
-
-	if len(tools) > 0 {
-		params.Tools = translateToolsForClaude(tools)
-	}
-
-	return params, nil
-}
-
-func translateToolsForClaude(tools []ToolDefinition) []anthropic.ToolUnionParam {
-	result := make([]anthropic.ToolUnionParam, 0, len(tools))
-	for _, t := range tools {
-		tool := anthropic.ToolParam{
-			Name: t.Function.Name,
-			InputSchema: anthropic.ToolInputSchemaParam{
-				Properties: t.Function.Parameters["properties"],
-			},
-		}
-		if desc := t.Function.Description; desc != "" {
-			tool.Description = anthropic.String(desc)
-		}
-		if req, ok := t.Function.Parameters["required"].([]interface{}); ok {
-			required := make([]string, 0, len(req))
-			for _, r := range req {
-				if s, ok := r.(string); ok {
-					required = append(required, s)
-				}
-			}
-			tool.InputSchema.Required = required
-		}
-		result = append(result, anthropic.ToolUnionParam{OfTool: &tool})
-	}
-	return result
-}
-
-func parseClaudeResponse(resp *anthropic.Message) *LLMResponse {
-	var content string
-	var toolCalls []ToolCall
-
-	for _, block := range resp.Content {
-		switch block.Type {
-		case "text":
-			tb := block.AsText()
-			content += tb.Text
-		case "tool_use":
-			tu := block.AsToolUse()
-			var args map[string]interface{}
-			if err := json.Unmarshal(tu.Input, &args); err != nil {
-				args = map[string]interface{}{"raw": string(tu.Input)}
-			}
-			toolCalls = append(toolCalls, ToolCall{
-				ID:        tu.ID,
-				Name:      tu.Name,
-				Arguments: args,
-			})
-		}
-	}
-
-	finishReason := "stop"
-	switch resp.StopReason {
-	case anthropic.StopReasonToolUse:
-		finishReason = "tool_calls"
-	case anthropic.StopReasonMaxTokens:
-		finishReason = "length"
-	case anthropic.StopReasonEndTurn:
-		finishReason = "stop"
-	}
-
-	return &LLMResponse{
-		Content:      content,
-		ToolCalls:    toolCalls,
-		FinishReason: finishReason,
-		Usage: &UsageInfo{
-			PromptTokens:     int(resp.Usage.InputTokens),
-			CompletionTokens: int(resp.Usage.OutputTokens),
-			TotalTokens:      int(resp.Usage.InputTokens + resp.Usage.OutputTokens),
-		},
-	}
+	return p.delegate.GetDefaultModel()
 }
 
 func createClaudeTokenSource() func() (string, error) {
@@ -205,3 +58,95 @@ func createClaudeTokenSource() func() (string, error) {
 		return cred.AccessToken, nil
 	}
 }
+
+func toAnthropicProviderMessages(messages []Message) []anthropicprovider.Message {
+	out := make([]anthropicprovider.Message, 0, len(messages))
+	for _, msg := range messages {
+		out = append(out, anthropicprovider.Message{
+			Role:       msg.Role,
+			Content:    msg.Content,
+			ToolCalls:  toAnthropicProviderToolCalls(msg.ToolCalls),
+			ToolCallID: msg.ToolCallID,
+		})
+	}
+	return out
+}
+
+func toAnthropicProviderTools(tools []ToolDefinition) []anthropicprovider.ToolDefinition {
+	out := make([]anthropicprovider.ToolDefinition, 0, len(tools))
+	for _, t := range tools {
+		out = append(out, anthropicprovider.ToolDefinition{
+			Type: t.Type,
+			Function: anthropicprovider.ToolFunctionDefinition{
+				Name:        t.Function.Name,
+				Description: t.Function.Description,
+				Parameters:  t.Function.Parameters,
+			},
+		})
+	}
+	return out
+}
+
+func toAnthropicProviderToolCalls(toolCalls []ToolCall) []anthropicprovider.ToolCall {
+	out := make([]anthropicprovider.ToolCall, 0, len(toolCalls))
+	for _, tc := range toolCalls {
+		var fn *anthropicprovider.FunctionCall
+		if tc.Function != nil {
+			fn = &anthropicprovider.FunctionCall{
+				Name:      tc.Function.Name,
+				Arguments: tc.Function.Arguments,
+			}
+		}
+		out = append(out, anthropicprovider.ToolCall{
+			ID:        tc.ID,
+			Type:      tc.Type,
+			Function:  fn,
+			Name:      tc.Name,
+			Arguments: tc.Arguments,
+		})
+	}
+	return out
+}
+
+func fromAnthropicProviderResponse(resp *anthropicprovider.LLMResponse) *LLMResponse {
+	if resp == nil {
+		return &LLMResponse{}
+	}
+
+	var usage *UsageInfo
+	if resp.Usage != nil {
+		usage = &UsageInfo{
+			PromptTokens:     resp.Usage.PromptTokens,
+			CompletionTokens: resp.Usage.CompletionTokens,
+			TotalTokens:      resp.Usage.TotalTokens,
+		}
+	}
+
+	return &LLMResponse{
+		Content:      resp.Content,
+		ToolCalls:    fromAnthropicProviderToolCalls(resp.ToolCalls),
+		FinishReason: resp.FinishReason,
+		Usage:        usage,
+	}
+}
+
+func fromAnthropicProviderToolCalls(toolCalls []anthropicprovider.ToolCall) []ToolCall {
+	out := make([]ToolCall, 0, len(toolCalls))
+	for _, tc := range toolCalls {
+		var fn *FunctionCall
+		if tc.Function != nil {
+			fn = &FunctionCall{
+				Name:      tc.Function.Name,
+				Arguments: tc.Function.Arguments,
+			}
+		}
+		out = append(out, ToolCall{
+			ID:        tc.ID,
+			Type:      tc.Type,
+			Function:  fn,
+			Name:      tc.Name,
+			Arguments: tc.Arguments,
+		})
+	}
+	return out
+}

pkg/providers/claude_provider_test.go

@@ -8,140 +8,9 @@ import (
 
 	"github.com/anthropics/anthropic-sdk-go"
 	anthropicoption "github.com/anthropics/anthropic-sdk-go/option"
+	anthropicprovider "github.com/sipeed/picoclaw/pkg/providers/anthropic"
 )
 
-func TestBuildClaudeParams_BasicMessage(t *testing.T) {
-	messages := []Message{
-		{Role: "user", Content: "Hello"},
-	}
-	params, err := buildClaudeParams(messages, nil, "claude-sonnet-4-5-20250929", map[string]interface{}{
-		"max_tokens": 1024,
-	})
-	if err != nil {
-		t.Fatalf("buildClaudeParams() error: %v", err)
-	}
-	if string(params.Model) != "claude-sonnet-4-5-20250929" {
-		t.Errorf("Model = %q, want %q", params.Model, "claude-sonnet-4-5-20250929")
-	}
-	if params.MaxTokens != 1024 {
-		t.Errorf("MaxTokens = %d, want 1024", params.MaxTokens)
-	}
-	if len(params.Messages) != 1 {
-		t.Fatalf("len(Messages) = %d, want 1", len(params.Messages))
-	}
-}
-
-func TestBuildClaudeParams_SystemMessage(t *testing.T) {
-	messages := []Message{
-		{Role: "system", Content: "You are helpful"},
-		{Role: "user", Content: "Hi"},
-	}
-	params, err := buildClaudeParams(messages, nil, "claude-sonnet-4-5-20250929", map[string]interface{}{})
-	if err != nil {
-		t.Fatalf("buildClaudeParams() error: %v", err)
-	}
-	if len(params.System) != 1 {
-		t.Fatalf("len(System) = %d, want 1", len(params.System))
-	}
-	if params.System[0].Text != "You are helpful" {
-		t.Errorf("System[0].Text = %q, want %q", params.System[0].Text, "You are helpful")
-	}
-	if len(params.Messages) != 1 {
-		t.Fatalf("len(Messages) = %d, want 1", len(params.Messages))
-	}
-}
-
-func TestBuildClaudeParams_ToolCallMessage(t *testing.T) {
-	messages := []Message{
-		{Role: "user", Content: "What's the weather?"},
-		{
-			Role:    "assistant",
-			Content: "",
-			ToolCalls: []ToolCall{
-				{
-					ID:        "call_1",
-					Name:      "get_weather",
-					Arguments: map[string]interface{}{"city": "SF"},
-				},
-			},
-		},
-		{Role: "tool", Content: `{"temp": 72}`, ToolCallID: "call_1"},
-	}
-	params, err := buildClaudeParams(messages, nil, "claude-sonnet-4-5-20250929", map[string]interface{}{})
-	if err != nil {
-		t.Fatalf("buildClaudeParams() error: %v", err)
-	}
-	if len(params.Messages) != 3 {
-		t.Fatalf("len(Messages) = %d, want 3", len(params.Messages))
-	}
-}
-
-func TestBuildClaudeParams_WithTools(t *testing.T) {
-	tools := []ToolDefinition{
-		{
-			Type: "function",
-			Function: ToolFunctionDefinition{
-				Name:        "get_weather",
-				Description: "Get weather for a city",
-				Parameters: map[string]interface{}{
-					"type": "object",
-					"properties": map[string]interface{}{
-						"city": map[string]interface{}{"type": "string"},
-					},
-					"required": []interface{}{"city"},
-				},
-			},
-		},
-	}
-	params, err := buildClaudeParams([]Message{{Role: "user", Content: "Hi"}}, tools, "claude-sonnet-4-5-20250929", map[string]interface{}{})
-	if err != nil {
-		t.Fatalf("buildClaudeParams() error: %v", err)
-	}
-	if len(params.Tools) != 1 {
-		t.Fatalf("len(Tools) = %d, want 1", len(params.Tools))
-	}
-}
-
-func TestParseClaudeResponse_TextOnly(t *testing.T) {
-	resp := &anthropic.Message{
-		Content: []anthropic.ContentBlockUnion{},
-		Usage: anthropic.Usage{
-			InputTokens:  10,
-			OutputTokens: 20,
-		},
-	}
-	result := parseClaudeResponse(resp)
-	if result.Usage.PromptTokens != 10 {
-		t.Errorf("PromptTokens = %d, want 10", result.Usage.PromptTokens)
-	}
-	if result.Usage.CompletionTokens != 20 {
-		t.Errorf("CompletionTokens = %d, want 20", result.Usage.CompletionTokens)
-	}
-	if result.FinishReason != "stop" {
-		t.Errorf("FinishReason = %q, want %q", result.FinishReason, "stop")
-	}
-}
-
-func TestParseClaudeResponse_StopReasons(t *testing.T) {
-	tests := []struct {
-		stopReason anthropic.StopReason
-		want       string
-	}{
-		{anthropic.StopReasonEndTurn, "stop"},
-		{anthropic.StopReasonMaxTokens, "length"},
-		{anthropic.StopReasonToolUse, "tool_calls"},
-	}
-	for _, tt := range tests {
-		resp := &anthropic.Message{
-			StopReason: tt.stopReason,
-		}
-		result := parseClaudeResponse(resp)
-		if result.FinishReason != tt.want {
-			t.Errorf("StopReason %q: FinishReason = %q, want %q", tt.stopReason, result.FinishReason, tt.want)
-		}
-	}
-}
-
 func TestClaudeProvider_ChatRoundTrip(t *testing.T) {
 	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		if r.URL.Path != "/v1/messages" {
@@ -175,8 +44,8 @@ func TestClaudeProvider_ChatRoundTrip(t *testing.T) {
 	}))
 	defer server.Close()
 
-	provider := NewClaudeProvider("test-token")
-	provider.client = createAnthropicTestClient(server.URL, "test-token")
+	delegate := anthropicprovider.NewProviderWithClient(createAnthropicTestClient(server.URL, "test-token"))
+	provider := newClaudeProviderWithDelegate(delegate)
 
 	messages := []Message{{Role: "user", Content: "Hello"}}
 	resp, err := provider.Chat(t.Context(), messages, nil, "claude-sonnet-4-5-20250929", map[string]interface{}{"max_tokens": 1024})