Refactor providers by protocol family (discussion #122)

README.md

@@ -679,6 +679,16 @@ The subagent has access to tools (message, web_search, etc.) and can communicate
 | `deepseek(To be tested)`   | LLM (DeepSeek direct)                   | [platform.deepseek.com](https://platform.deepseek.com) |
 | `groq`                     | LLM + **Voice transcription** (Whisper) | [console.groq.com](https://console.groq.com)           |
 
+### Provider Architecture
+
+PicoClaw routes providers by protocol family:
+
+- OpenAI-compatible protocol: OpenRouter, OpenAI-compatible gateways, Groq, Zhipu, and vLLM-style endpoints.
+- Anthropic protocol: Claude-native API behavior.
+- Codex/OAuth path: OpenAI OAuth/token authentication route.
+
+This keeps the runtime lightweight while making new OpenAI-compatible backends mostly a config operation (`api_base` + `api_key`).
+
 <details>
 <summary><b>Zhipu</b></summary>
 

pkg/migrate/migrate_test.go

@@ -299,6 +299,24 @@ func TestConvertConfig(t *testing.T) {
 	})
 }
 
+func TestSupportedProvidersCompatibility(t *testing.T) {
+	expected := []string{
+		"anthropic",
+		"openai",
+		"openrouter",
+		"groq",
+		"zhipu",
+		"vllm",
+		"gemini",
+	}
+
+	for _, provider := range expected {
+		if !supportedProviders[provider] {
+			t.Fatalf("supportedProviders missing expected key %q", provider)
+		}
+	}
+}
+
 func TestMergeConfig(t *testing.T) {
 	t.Run("fills empty fields", func(t *testing.T) {
 		existing := config.DefaultConfig()

pkg/providers/anthropic/provider.go

@@ -0,0 +1,248 @@
+package anthropicprovider
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"log"
+	"strings"
+
+	"github.com/anthropics/anthropic-sdk-go"
+	"github.com/anthropics/anthropic-sdk-go/option"
+	"github.com/sipeed/picoclaw/pkg/providers/protocoltypes"
+)
+
+type ToolCall = protocoltypes.ToolCall
+type FunctionCall = protocoltypes.FunctionCall
+type LLMResponse = protocoltypes.LLMResponse
+type UsageInfo = protocoltypes.UsageInfo
+type Message = protocoltypes.Message
+type ToolDefinition = protocoltypes.ToolDefinition
+type ToolFunctionDefinition = protocoltypes.ToolFunctionDefinition
+
+const defaultBaseURL = "https://api.anthropic.com"
+
+type Provider struct {
+	client      *anthropic.Client
+	tokenSource func() (string, error)
+	baseURL     string
+}
+
+func NewProvider(token string) *Provider {
+	return NewProviderWithBaseURL(token, "")
+}
+
+func NewProviderWithBaseURL(token, apiBase string) *Provider {
+	baseURL := normalizeBaseURL(apiBase)
+	client := anthropic.NewClient(
+		option.WithAuthToken(token),
+		option.WithBaseURL(baseURL),
+	)
+	return &Provider{
+		client:  &client,
+		baseURL: baseURL,
+	}
+}
+
+func NewProviderWithClient(client *anthropic.Client) *Provider {
+	return &Provider{
+		client:  client,
+		baseURL: defaultBaseURL,
+	}
+}
+
+func NewProviderWithTokenSource(token string, tokenSource func() (string, error)) *Provider {
+	return NewProviderWithTokenSourceAndBaseURL(token, tokenSource, "")
+}
+
+func NewProviderWithTokenSourceAndBaseURL(token string, tokenSource func() (string, error), apiBase string) *Provider {
+	p := NewProviderWithBaseURL(token, apiBase)
+	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 (p *Provider) BaseURL() string {
+	return p.baseURL
+}
+
+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 {
+				log.Printf("anthropic: failed to decode tool call input for %q: %v", tu.Name, err)
+				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),
+		},
+	}
+}
+
+func normalizeBaseURL(apiBase string) string {
+	base := strings.TrimSpace(apiBase)
+	if base == "" {
+		return defaultBaseURL
+	}
+
+	base = strings.TrimRight(base, "/")
+	if strings.HasSuffix(base, "/v1") {
+		base = strings.TrimSuffix(base, "/v1")
+	}
+	if base == "" {
+		return defaultBaseURL
+	}
+
+	return base
+}