refactor backend API structure

internal/httpapi/claude/convert.go

@@ -0,0 +1,11 @@
+package claude
+
+import (
+	"ds2api/internal/claudeconv"
+)
+
+const defaultClaudeModel = "claude-sonnet-4-6"
+
+func convertClaudeToDeepSeek(claudeReq map[string]any, store ConfigReader) map[string]any {
+	return claudeconv.ConvertClaudeToDeepSeek(claudeReq, store, defaultClaudeModel)
+}

internal/httpapi/claude/deps.go

@@ -0,0 +1,34 @@
+package claude
+
+import (
+	"context"
+	"net/http"
+
+	"ds2api/internal/auth"
+	"ds2api/internal/config"
+	dsclient "ds2api/internal/deepseek/client"
+)
+
+type AuthResolver interface {
+	Determine(req *http.Request) (*auth.RequestAuth, error)
+	Release(a *auth.RequestAuth)
+}
+
+type DeepSeekCaller interface {
+	CreateSession(ctx context.Context, a *auth.RequestAuth, maxAttempts int) (string, error)
+	GetPow(ctx context.Context, a *auth.RequestAuth, maxAttempts int) (string, error)
+	CallCompletion(ctx context.Context, a *auth.RequestAuth, payload map[string]any, powResp string, maxAttempts int) (*http.Response, error)
+}
+
+type ConfigReader interface {
+	ModelAliases() map[string]string
+	CompatStripReferenceMarkers() bool
+}
+
+type OpenAIChatRunner interface {
+	ChatCompletions(w http.ResponseWriter, r *http.Request)
+}
+
+var _ AuthResolver = (*auth.Resolver)(nil)
+var _ DeepSeekCaller = (*dsclient.Client)(nil)
+var _ ConfigReader = (*config.Store)(nil)

internal/httpapi/claude/deps_injection_test.go

@@ -0,0 +1,74 @@
+package claude
+
+import "testing"
+
+type mockClaudeConfig struct {
+	aliases map[string]string
+}
+
+func (m mockClaudeConfig) ModelAliases() map[string]string { return m.aliases }
+func (mockClaudeConfig) CompatStripReferenceMarkers() bool { return true }
+
+func TestNormalizeClaudeRequestUsesGlobalAliasMapping(t *testing.T) {
+	req := map[string]any{
+		"model": "claude-opus-4-6",
+		"messages": []any{
+			map[string]any{"role": "user", "content": "hello"},
+		},
+	}
+	out, err := normalizeClaudeRequest(mockClaudeConfig{
+		aliases: map[string]string{
+			"claude-opus-4-6": "deepseek-v4-pro-search",
+		},
+	}, req)
+	if err != nil {
+		t.Fatalf("normalizeClaudeRequest error: %v", err)
+	}
+	if out.Standard.ResolvedModel != "deepseek-v4-pro-search" {
+		t.Fatalf("resolved model mismatch: got=%q", out.Standard.ResolvedModel)
+	}
+	if out.Standard.Thinking || !out.Standard.Search {
+		t.Fatalf("unexpected flags: thinking=%v search=%v", out.Standard.Thinking, out.Standard.Search)
+	}
+}
+
+func TestNormalizeClaudeRequestEnablesThinkingWhenRequested(t *testing.T) {
+	req := map[string]any{
+		"model": "claude-opus-4-6",
+		"messages": []any{
+			map[string]any{"role": "user", "content": "hello"},
+		},
+		"thinking": map[string]any{"type": "enabled", "budget_tokens": 1024},
+	}
+	out, err := normalizeClaudeRequest(mockClaudeConfig{
+		aliases: map[string]string{
+			"claude-opus-4-6": "deepseek-v4-pro",
+		},
+	}, req)
+	if err != nil {
+		t.Fatalf("normalizeClaudeRequest error: %v", err)
+	}
+	if !out.Standard.Thinking {
+		t.Fatalf("expected explicit Claude thinking request to enable downstream thinking")
+	}
+}
+
+func TestNormalizeClaudeRequestPrefersGlobalAliasMapping(t *testing.T) {
+	req := map[string]any{
+		"model": "claude-sonnet-4-6",
+		"messages": []any{
+			map[string]any{"role": "user", "content": "hello"},
+		},
+	}
+	out, err := normalizeClaudeRequest(mockClaudeConfig{
+		aliases: map[string]string{
+			"claude-sonnet-4-6": "deepseek-v4-flash",
+		},
+	}, req)
+	if err != nil {
+		t.Fatalf("normalizeClaudeRequest error: %v", err)
+	}
+	if out.Standard.ResolvedModel != "deepseek-v4-flash" {
+		t.Fatalf("expected global alias to win for explicit model, got=%q", out.Standard.ResolvedModel)
+	}
+}

internal/httpapi/claude/error_shape_test.go

@@ -0,0 +1,34 @@
+package claude
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestWriteClaudeErrorIncludesUnifiedFields(t *testing.T) {
+	rec := httptest.NewRecorder()
+	writeClaudeError(rec, http.StatusUnauthorized, "bad token")
+	if rec.Code != http.StatusUnauthorized {
+		t.Fatalf("expected 401, got %d", rec.Code)
+	}
+
+	var body map[string]any
+	if err := json.Unmarshal(rec.Body.Bytes(), &body); err != nil {
+		t.Fatalf("decode body: %v", err)
+	}
+	errObj, _ := body["error"].(map[string]any)
+	if errObj["message"] != "bad token" {
+		t.Fatalf("unexpected message: %v", errObj["message"])
+	}
+	if errObj["type"] != "invalid_request_error" {
+		t.Fatalf("unexpected type: %v", errObj["type"])
+	}
+	if errObj["code"] != "authentication_failed" {
+		t.Fatalf("unexpected code: %v", errObj["code"])
+	}
+	if _, ok := errObj["param"]; !ok {
+		t.Fatal("expected param field")
+	}
+}

internal/httpapi/claude/handler_errors.go

@@ -0,0 +1,25 @@
+package claude
+
+import "net/http"
+
+func writeClaudeError(w http.ResponseWriter, status int, message string) {
+	code := "invalid_request"
+	switch status {
+	case http.StatusUnauthorized:
+		code = "authentication_failed"
+	case http.StatusTooManyRequests:
+		code = "rate_limit_exceeded"
+	case http.StatusNotFound:
+		code = "not_found"
+	case http.StatusInternalServerError:
+		code = "internal_error"
+	}
+	writeJSON(w, status, map[string]any{
+		"error": map[string]any{
+			"type":    "invalid_request_error",
+			"message": message,
+			"code":    code,
+			"param":   nil,
+		},
+	})
+}

internal/httpapi/claude/handler_helpers_misc.go

@@ -0,0 +1,97 @@
+package claude
+
+import (
+	"fmt"
+	"strings"
+)
+
+func hasSystemMessage(messages []any) bool {
+	for _, m := range messages {
+		msg, ok := m.(map[string]any)
+		if ok && msg["role"] == "system" {
+			return true
+		}
+	}
+	return false
+}
+
+func extractClaudeToolNames(tools []any) []string {
+	out := make([]string, 0, len(tools))
+	for _, t := range tools {
+		m, ok := t.(map[string]any)
+		if !ok {
+			continue
+		}
+		name, _, _ := extractClaudeToolMeta(m)
+		if name != "" {
+			out = append(out, name)
+		}
+	}
+	return out
+}
+
+func extractClaudeToolMeta(m map[string]any) (string, string, any) {
+	name, _ := m["name"].(string)
+	desc, _ := m["description"].(string)
+	schemaObj := m["input_schema"]
+	if schemaObj == nil {
+		schemaObj = m["parameters"]
+	}
+
+	if fn, ok := m["function"].(map[string]any); ok {
+		if strings.TrimSpace(name) == "" {
+			name, _ = fn["name"].(string)
+		}
+		if strings.TrimSpace(desc) == "" {
+			desc, _ = fn["description"].(string)
+		}
+		if schemaObj == nil {
+			if v, ok := fn["input_schema"]; ok {
+				schemaObj = v
+			}
+		}
+		if schemaObj == nil {
+			if v, ok := fn["parameters"]; ok {
+				schemaObj = v
+			}
+		}
+	}
+	return strings.TrimSpace(name), strings.TrimSpace(desc), schemaObj
+}
+
+func toMessageMaps(v any) []map[string]any {
+	arr, ok := v.([]any)
+	if !ok {
+		return nil
+	}
+	out := make([]map[string]any, 0, len(arr))
+	for _, item := range arr {
+		if m, ok := item.(map[string]any); ok {
+			out = append(out, m)
+		}
+	}
+	return out
+}
+
+func extractMessageContent(v any) string {
+	switch x := v.(type) {
+	case string:
+		return x
+	case []any:
+		parts := make([]string, 0, len(x))
+		for _, it := range x {
+			parts = append(parts, fmt.Sprintf("%v", it))
+		}
+		return strings.Join(parts, "\n")
+	default:
+		return fmt.Sprintf("%v", x)
+	}
+}
+
+func cloneMap(in map[string]any) map[string]any {
+	out := make(map[string]any, len(in))
+	for k, v := range in {
+		out[k] = v
+	}
+	return out
+}

internal/httpapi/claude/handler_messages.go

@@ -0,0 +1,201 @@
+package claude
+
+import (
+	"bytes"
+	"encoding/json"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+
+	"ds2api/internal/config"
+	streamengine "ds2api/internal/stream"
+	"ds2api/internal/translatorcliproxy"
+	"ds2api/internal/util"
+
+	sdktranslator "github.com/router-for-me/CLIProxyAPI/v6/sdk/translator"
+)
+
+func (h *Handler) Messages(w http.ResponseWriter, r *http.Request) {
+	if strings.TrimSpace(r.Header.Get("anthropic-version")) == "" {
+		r.Header.Set("anthropic-version", "2023-06-01")
+	}
+	if h.OpenAI == nil {
+		writeClaudeError(w, http.StatusInternalServerError, "OpenAI proxy backend unavailable.")
+		return
+	}
+	if h.proxyViaOpenAI(w, r, h.Store) {
+		return
+	}
+	writeClaudeError(w, http.StatusBadGateway, "Failed to proxy Claude request.")
+}
+
+func (h *Handler) proxyViaOpenAI(w http.ResponseWriter, r *http.Request, store ConfigReader) bool {
+	raw, err := io.ReadAll(r.Body)
+	if err != nil {
+		writeClaudeError(w, http.StatusBadRequest, "invalid body")
+		return true
+	}
+	var req map[string]any
+	if err := json.Unmarshal(raw, &req); err != nil {
+		writeClaudeError(w, http.StatusBadRequest, "invalid json")
+		return true
+	}
+	model, _ := req["model"].(string)
+	stream := util.ToBool(req["stream"])
+
+	// Use the shared global model resolver so Claude/OpenAI/Gemini stay consistent.
+	translateModel := model
+	if store != nil {
+		if norm, normErr := normalizeClaudeRequest(store, cloneMap(req)); normErr == nil && strings.TrimSpace(norm.Standard.ResolvedModel) != "" {
+			translateModel = strings.TrimSpace(norm.Standard.ResolvedModel)
+		}
+	}
+	translatedReq := translatorcliproxy.ToOpenAI(sdktranslator.FormatClaude, translateModel, raw, stream)
+	translatedReq = applyClaudeThinkingPolicyToOpenAIRequest(translatedReq, req)
+
+	isVercelPrepare := strings.TrimSpace(r.URL.Query().Get("__stream_prepare")) == "1"
+	isVercelRelease := strings.TrimSpace(r.URL.Query().Get("__stream_release")) == "1"
+
+	if isVercelRelease {
+		proxyReq := r.Clone(r.Context())
+		proxyReq.URL.Path = "/v1/chat/completions"
+		proxyReq.Body = io.NopCloser(bytes.NewReader(raw))
+		proxyReq.ContentLength = int64(len(raw))
+		rec := httptest.NewRecorder()
+		h.OpenAI.ChatCompletions(rec, proxyReq)
+		res := rec.Result()
+		defer func() { _ = res.Body.Close() }()
+		body, _ := io.ReadAll(res.Body)
+		for k, vv := range res.Header {
+			for _, v := range vv {
+				w.Header().Add(k, v)
+			}
+		}
+		w.WriteHeader(res.StatusCode)
+		_, _ = w.Write(body)
+		return true
+	}
+
+	proxyReq := r.Clone(r.Context())
+	proxyReq.URL.Path = "/v1/chat/completions"
+	proxyReq.Body = io.NopCloser(bytes.NewReader(translatedReq))
+	proxyReq.ContentLength = int64(len(translatedReq))
+
+	if stream && !isVercelPrepare {
+		w.Header().Set("Content-Type", "text/event-stream")
+		w.Header().Set("Cache-Control", "no-cache, no-transform")
+		w.Header().Set("Connection", "keep-alive")
+		w.Header().Set("X-Accel-Buffering", "no")
+		streamWriter := translatorcliproxy.NewOpenAIStreamTranslatorWriter(w, sdktranslator.FormatClaude, model, raw, translatedReq)
+		h.OpenAI.ChatCompletions(streamWriter, proxyReq)
+		return true
+	}
+
+	rec := httptest.NewRecorder()
+	h.OpenAI.ChatCompletions(rec, proxyReq)
+	res := rec.Result()
+	defer func() { _ = res.Body.Close() }()
+	body, _ := io.ReadAll(res.Body)
+	if res.StatusCode < 200 || res.StatusCode >= 300 {
+		for k, vv := range res.Header {
+			for _, v := range vv {
+				w.Header().Add(k, v)
+			}
+		}
+		w.WriteHeader(res.StatusCode)
+		_, _ = w.Write(body)
+		return true
+	}
+	if isVercelPrepare {
+		for k, vv := range res.Header {
+			for _, v := range vv {
+				w.Header().Add(k, v)
+			}
+		}
+		w.WriteHeader(res.StatusCode)
+		_, _ = w.Write(body)
+		return true
+	}
+	converted := translatorcliproxy.FromOpenAINonStream(sdktranslator.FormatClaude, model, raw, translatedReq, body)
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(http.StatusOK)
+	_, _ = w.Write(converted)
+	return true
+}
+
+func applyClaudeThinkingPolicyToOpenAIRequest(translated []byte, original map[string]any) []byte {
+	req := map[string]any{}
+	if err := json.Unmarshal(translated, &req); err != nil {
+		return translated
+	}
+	enabled, ok := util.ResolveThinkingOverride(original)
+	if !ok {
+		if _, translatedHasOverride := util.ResolveThinkingOverride(req); translatedHasOverride {
+			return translated
+		}
+		enabled = false
+	}
+	typ := "disabled"
+	if enabled {
+		typ = "enabled"
+	}
+	req["thinking"] = map[string]any{"type": typ}
+	out, err := json.Marshal(req)
+	if err != nil {
+		return translated
+	}
+	return out
+}
+
+func (h *Handler) handleClaudeStreamRealtime(w http.ResponseWriter, r *http.Request, resp *http.Response, model string, messages []any, thinkingEnabled, searchEnabled bool, toolNames []string) {
+	defer func() { _ = resp.Body.Close() }()
+	if resp.StatusCode != http.StatusOK {
+		body, _ := io.ReadAll(resp.Body)
+		writeClaudeError(w, http.StatusInternalServerError, string(body))
+		return
+	}
+
+	w.Header().Set("Content-Type", "text/event-stream")
+	w.Header().Set("Cache-Control", "no-cache, no-transform")
+	w.Header().Set("Connection", "keep-alive")
+	w.Header().Set("X-Accel-Buffering", "no")
+	rc := http.NewResponseController(w)
+	_, canFlush := w.(http.Flusher)
+	if !canFlush {
+		config.Logger.Warn("[claude_stream] response writer does not support flush; streaming may be buffered")
+	}
+
+	streamRuntime := newClaudeStreamRuntime(
+		w,
+		rc,
+		canFlush,
+		model,
+		messages,
+		thinkingEnabled,
+		searchEnabled,
+		h.compatStripReferenceMarkers(),
+		toolNames,
+	)
+	streamRuntime.sendMessageStart()
+
+	initialType := "text"
+	if thinkingEnabled {
+		initialType = "thinking"
+	}
+	streamengine.ConsumeSSE(streamengine.ConsumeConfig{
+		Context:             r.Context(),
+		Body:                resp.Body,
+		ThinkingEnabled:     thinkingEnabled,
+		InitialType:         initialType,
+		KeepAliveInterval:   claudeStreamPingInterval,
+		IdleTimeout:         claudeStreamIdleTimeout,
+		MaxKeepAliveNoInput: claudeStreamMaxKeepaliveCnt,
+	}, streamengine.ConsumeHooks{
+		OnKeepAlive: func() {
+			streamRuntime.sendPing()
+		},
+		OnParsed:   streamRuntime.onParsed,
+		OnFinalize: streamRuntime.onFinalize,
+	})
+}

internal/httpapi/claude/handler_routes.go

@@ -0,0 +1,49 @@
+package claude
+
+import (
+	"net/http"
+	"time"
+
+	"github.com/go-chi/chi/v5"
+
+	"ds2api/internal/config"
+	dsprotocol "ds2api/internal/deepseek/protocol"
+	"ds2api/internal/util"
+)
+
+// writeJSON is a package-internal alias to avoid mass-renaming all call-sites.
+var writeJSON = util.WriteJSON
+
+type Handler struct {
+	Store  ConfigReader
+	Auth   AuthResolver
+	DS     DeepSeekCaller
+	OpenAI OpenAIChatRunner
+}
+
+func (h *Handler) compatStripReferenceMarkers() bool {
+	if h == nil || h.Store == nil {
+		return true
+	}
+	return h.Store.CompatStripReferenceMarkers()
+}
+
+var (
+	claudeStreamPingInterval    = time.Duration(dsprotocol.KeepAliveTimeout) * time.Second
+	claudeStreamIdleTimeout     = time.Duration(dsprotocol.StreamIdleTimeout) * time.Second
+	claudeStreamMaxKeepaliveCnt = dsprotocol.MaxKeepaliveCount
+)
+
+func RegisterRoutes(r chi.Router, h *Handler) {
+	r.Get("/anthropic/v1/models", h.ListModels)
+	r.Post("/anthropic/v1/messages", h.Messages)
+	r.Post("/anthropic/v1/messages/count_tokens", h.CountTokens)
+	r.Post("/v1/messages", h.Messages)
+	r.Post("/messages", h.Messages)
+	r.Post("/v1/messages/count_tokens", h.CountTokens)
+	r.Post("/messages/count_tokens", h.CountTokens)
+}
+
+func (h *Handler) ListModels(w http.ResponseWriter, _ *http.Request) {
+	writeJSON(w, http.StatusOK, config.ClaudeModelsResponse())
+}

internal/httpapi/claude/handler_stream_test.go

@@ -0,0 +1,367 @@
+package claude
+
+import (
+	"ds2api/internal/sse"
+	"encoding/json"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+	"time"
+)
+
+type claudeFrame struct {
+	Event   string
+	Payload map[string]any
+}
+
+func makeClaudeSSEHTTPResponse(lines ...string) *http.Response {
+	body := strings.Join(lines, "\n")
+	if !strings.HasSuffix(body, "\n") {
+		body += "\n"
+	}
+	return &http.Response{
+		StatusCode: http.StatusOK,
+		Header:     make(http.Header),
+		Body:       io.NopCloser(strings.NewReader(body)),
+	}
+}
+
+func parseClaudeFrames(t *testing.T, body string) []claudeFrame {
+	t.Helper()
+	chunks := strings.Split(body, "\n\n")
+	frames := make([]claudeFrame, 0, len(chunks))
+	for _, chunk := range chunks {
+		chunk = strings.TrimSpace(chunk)
+		if chunk == "" {
+			continue
+		}
+		lines := strings.Split(chunk, "\n")
+		eventName := ""
+		dataPayload := ""
+		for _, line := range lines {
+			line = strings.TrimSpace(line)
+			switch {
+			case strings.HasPrefix(line, "event:"):
+				eventName = strings.TrimSpace(strings.TrimPrefix(line, "event:"))
+			case strings.HasPrefix(line, "data:"):
+				dataPayload = strings.TrimSpace(strings.TrimPrefix(line, "data:"))
+			}
+		}
+		if eventName == "" || dataPayload == "" {
+			continue
+		}
+		var payload map[string]any
+		if err := json.Unmarshal([]byte(dataPayload), &payload); err != nil {
+			t.Fatalf("decode frame failed: %v, payload=%s", err, dataPayload)
+		}
+		frames = append(frames, claudeFrame{Event: eventName, Payload: payload})
+	}
+	return frames
+}
+
+func findClaudeFrames(frames []claudeFrame, event string) []claudeFrame {
+	out := make([]claudeFrame, 0)
+	for _, f := range frames {
+		if f.Event == event {
+			out = append(out, f)
+		}
+	}
+	return out
+}
+
+func TestHandleClaudeStreamRealtimeTextIncrementsWithEventHeaders(t *testing.T) {
+	h := &Handler{}
+	resp := makeClaudeSSEHTTPResponse(
+		`data: {"p":"response/content","v":"Hel"}`,
+		`data: {"p":"response/content","v":"lo"}`,
+		`data: [DONE]`,
+	)
+	rec := httptest.NewRecorder()
+	req := httptest.NewRequest(http.MethodPost, "/anthropic/v1/messages", nil)
+
+	h.handleClaudeStreamRealtime(rec, req, resp, "claude-sonnet-4-5", []any{map[string]any{"role": "user", "content": "hi"}}, false, false, nil)
+
+	body := rec.Body.String()
+	if !strings.Contains(body, "event: message_start") {
+		t.Fatalf("missing event header: message_start, body=%s", body)
+	}
+	if !strings.Contains(body, "event: content_block_delta") {
+		t.Fatalf("missing event header: content_block_delta, body=%s", body)
+	}
+	if !strings.Contains(body, "event: message_stop") {
+		t.Fatalf("missing event header: message_stop, body=%s", body)
+	}
+
+	frames := parseClaudeFrames(t, body)
+	deltas := findClaudeFrames(frames, "content_block_delta")
+	if len(deltas) < 2 {
+		t.Fatalf("expected at least 2 text deltas, got=%d body=%s", len(deltas), body)
+	}
+	combined := strings.Builder{}
+	for _, f := range deltas {
+		delta, _ := f.Payload["delta"].(map[string]any)
+		if delta["type"] == "text_delta" {
+			combined.WriteString(asString(delta["text"]))
+		}
+	}
+	if combined.String() != "Hello" {
+		t.Fatalf("unexpected combined text: %q body=%s", combined.String(), body)
+	}
+}
+
+func TestHandleClaudeStreamRealtimeThinkingDelta(t *testing.T) {
+	h := &Handler{}
+	resp := makeClaudeSSEHTTPResponse(
+		`data: {"p":"response/thinking_content","v":"思"}`,
+		`data: {"p":"response/thinking_content","v":"考"}`,
+		`data: {"p":"response/content","v":"ok"}`,
+		`data: [DONE]`,
+	)
+	rec := httptest.NewRecorder()
+	req := httptest.NewRequest(http.MethodPost, "/anthropic/v1/messages", nil)
+
+	h.handleClaudeStreamRealtime(rec, req, resp, "claude-sonnet-4-5", []any{map[string]any{"role": "user", "content": "hi"}}, true, false, nil)
+
+	frames := parseClaudeFrames(t, rec.Body.String())
+	foundThinkingDelta := false
+	for _, f := range findClaudeFrames(frames, "content_block_delta") {
+		delta, _ := f.Payload["delta"].(map[string]any)
+		if delta["type"] == "thinking_delta" {
+			foundThinkingDelta = true
+			break
+		}
+	}
+	if !foundThinkingDelta {
+		t.Fatalf("expected thinking_delta event, body=%s", rec.Body.String())
+	}
+}
+
+func TestHandleClaudeStreamRealtimeSkipsThinkingFallbackWhenFinalTextExists(t *testing.T) {
+	h := &Handler{}
+	resp := makeClaudeSSEHTTPResponse(
+		`data: {"p":"response/thinking_content","v":"{\"tool_calls\":[{\"name\":\"search\""}`,
+		`data: {"p":"response/thinking_content","v":",\"input\":{\"q\":\"go\"}}]}"}`,
+		`data: {"p":"response/content","v":"normal answer"}`,
+		`data: [DONE]`,
+	)
+	rec := httptest.NewRecorder()
+	req := httptest.NewRequest(http.MethodPost, "/anthropic/v1/messages", nil)
+
+	h.handleClaudeStreamRealtime(rec, req, resp, "claude-sonnet-4-5", []any{map[string]any{"role": "user", "content": "use tool"}}, true, false, []string{"search"})
+
+	frames := parseClaudeFrames(t, rec.Body.String())
+	for _, f := range findClaudeFrames(frames, "content_block_start") {
+		contentBlock, _ := f.Payload["content_block"].(map[string]any)
+		if contentBlock["type"] == "tool_use" {
+			t.Fatalf("unexpected tool_use block when final text exists, body=%s", rec.Body.String())
+		}
+	}
+
+	foundEndTurn := false
+	for _, f := range findClaudeFrames(frames, "message_delta") {
+		delta, _ := f.Payload["delta"].(map[string]any)
+		if delta["stop_reason"] == "end_turn" {
+			foundEndTurn = true
+			break
+		}
+	}
+	if !foundEndTurn {
+		t.Fatalf("expected stop_reason=end_turn, body=%s", rec.Body.String())
+	}
+}
+
+func TestHandleClaudeStreamRealtimeUpstreamErrorEvent(t *testing.T) {
+	h := &Handler{}
+	resp := makeClaudeSSEHTTPResponse(
+		`data: {"error":{"message":"boom"}}`,
+	)
+	rec := httptest.NewRecorder()
+	req := httptest.NewRequest(http.MethodPost, "/anthropic/v1/messages", nil)
+
+	h.handleClaudeStreamRealtime(rec, req, resp, "claude-sonnet-4-5", []any{map[string]any{"role": "user", "content": "hi"}}, false, false, nil)
+
+	frames := parseClaudeFrames(t, rec.Body.String())
+	errFrames := findClaudeFrames(frames, "error")
+	if len(errFrames) == 0 {
+		t.Fatalf("expected error event frame, body=%s", rec.Body.String())
+	}
+	if errFrames[0].Payload["type"] != "error" {
+		t.Fatalf("expected error payload type, body=%s", rec.Body.String())
+	}
+}
+
+func TestHandleClaudeStreamRealtimePingEvent(t *testing.T) {
+	h := &Handler{}
+	oldPing := claudeStreamPingInterval
+	oldIdle := claudeStreamIdleTimeout
+	oldKeepalive := claudeStreamMaxKeepaliveCnt
+	claudeStreamPingInterval = 10 * time.Millisecond
+	claudeStreamIdleTimeout = 300 * time.Millisecond
+	claudeStreamMaxKeepaliveCnt = 50
+	defer func() {
+		claudeStreamPingInterval = oldPing
+		claudeStreamIdleTimeout = oldIdle
+		claudeStreamMaxKeepaliveCnt = oldKeepalive
+	}()
+
+	pr, pw := io.Pipe()
+	resp := &http.Response{StatusCode: http.StatusOK, Header: make(http.Header), Body: pr}
+	go func() {
+		time.Sleep(40 * time.Millisecond)
+		_, _ = io.WriteString(pw, "data: {\"p\":\"response/content\",\"v\":\"hi\"}\n")
+		_, _ = io.WriteString(pw, "data: [DONE]\n")
+		_ = pw.Close()
+	}()
+
+	rec := httptest.NewRecorder()
+	req := httptest.NewRequest(http.MethodPost, "/anthropic/v1/messages", nil)
+	h.handleClaudeStreamRealtime(rec, req, resp, "claude-sonnet-4-5", []any{map[string]any{"role": "user", "content": "hi"}}, false, false, nil)
+
+	frames := parseClaudeFrames(t, rec.Body.String())
+	if len(findClaudeFrames(frames, "ping")) == 0 {
+		t.Fatalf("expected ping event in stream, body=%s", rec.Body.String())
+	}
+}
+
+func TestCollectDeepSeekRegression(t *testing.T) {
+	resp := makeClaudeSSEHTTPResponse(
+		`data: {"p":"response/thinking_content","v":"想"}`,
+		`data: {"p":"response/content","v":"答"}`,
+		`data: [DONE]`,
+	)
+	result := sse.CollectStream(resp, true, true)
+	if result.Thinking != "想" {
+		t.Fatalf("unexpected thinking: %q", result.Thinking)
+	}
+	if result.Text != "答" {
+		t.Fatalf("unexpected text: %q", result.Text)
+	}
+}
+
+func asString(v any) string {
+	s, _ := v.(string)
+	return s
+}
+
+func TestHandleClaudeStreamRealtimeToolSafetyAcrossStructuredFormats(t *testing.T) {
+	tests := []struct {
+		name        string
+		payload     string
+		wantToolUse bool
+	}{
+		{name: "invoke_parameter_wrapper", payload: `<tool_calls><invoke name="Bash"><parameter name="command">pwd</parameter></invoke></tool_calls>`, wantToolUse: true},
+		{name: "legacy_single_tool_root", payload: `<tool><tool_name>Bash</tool_name><param><command>pwd</command></param></tool>`, wantToolUse: false},
+		{name: "legacy_tool_call_json", payload: `<tool>{"tool":"Bash","params":{"command":"pwd"}}</tool>`, wantToolUse: false},
+		{name: "legacy_nested_tool_tag_style", payload: `<tool><tool name="Bash"><command>pwd</command></tool_call></tool>`, wantToolUse: false},
+		{name: "legacy_function_tag_style", payload: `<function_call>Bash</function_call><function parameter name="command">pwd</function parameter>`, wantToolUse: false},
+		{name: "legacy_antml_argument_style", payload: `<antml:function_calls><antml:function_call id="1" name="Bash"><antml:argument name="command">pwd</antml:argument></antml:function_call></antml:function_calls>`, wantToolUse: false},
+		{name: "legacy_antml_function_attr_parameters", payload: `<antml:function_calls><antml:function_call id="1" function="Bash"><antml:parameters>{"command":"pwd"}</antml:parameters></antml:function_call></antml:function_calls>`, wantToolUse: false},
+		{name: "legacy_function_calls_wrapper", payload: `<function_calls><invoke name="Bash"><parameter name="command">pwd</parameter></invoke></function_calls>`, wantToolUse: false},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			h := &Handler{}
+			resp := makeClaudeSSEHTTPResponse(
+				`data: {"p":"response/content","v":"`+strings.ReplaceAll(tc.payload, `"`, `\"`)+`"}`,
+				`data: [DONE]`,
+			)
+			rec := httptest.NewRecorder()
+			req := httptest.NewRequest(http.MethodPost, "/anthropic/v1/messages", nil)
+
+			h.handleClaudeStreamRealtime(rec, req, resp, "claude-sonnet-4-5", []any{map[string]any{"role": "user", "content": "use tool"}}, false, false, []string{"Bash"})
+
+			frames := parseClaudeFrames(t, rec.Body.String())
+			foundToolUse := false
+			for _, f := range findClaudeFrames(frames, "content_block_start") {
+				contentBlock, _ := f.Payload["content_block"].(map[string]any)
+				if contentBlock["type"] == "tool_use" {
+					foundToolUse = true
+					break
+				}
+			}
+			if foundToolUse != tc.wantToolUse {
+				t.Fatalf("unexpected tool_use=%v for format %s, body=%s", foundToolUse, tc.name, rec.Body.String())
+			}
+		})
+	}
+}
+
+func TestHandleClaudeStreamRealtimeDetectsToolUseWithLeadingProse(t *testing.T) {
+	h := &Handler{}
+	payload := "I'll call a tool now.\\n<tool_calls><invoke name=\\\"write_file\\\"><parameter name=\\\"path\\\">/tmp/a.txt</parameter><parameter name=\\\"content\\\">abc</parameter></invoke></tool_calls>"
+	resp := makeClaudeSSEHTTPResponse(
+		`data: {"p":"response/content","v":"`+payload+`"}`,
+		`data: [DONE]`,
+	)
+	rec := httptest.NewRecorder()
+	req := httptest.NewRequest(http.MethodPost, "/anthropic/v1/messages", nil)
+
+	h.handleClaudeStreamRealtime(rec, req, resp, "claude-sonnet-4-5", []any{map[string]any{"role": "user", "content": "use tool"}}, false, false, []string{"write_file"})
+
+	frames := parseClaudeFrames(t, rec.Body.String())
+	foundToolUse := false
+	for _, f := range findClaudeFrames(frames, "content_block_start") {
+		contentBlock, _ := f.Payload["content_block"].(map[string]any)
+		if contentBlock["type"] == "tool_use" && contentBlock["name"] == "write_file" {
+			foundToolUse = true
+			break
+		}
+	}
+	if !foundToolUse {
+		t.Fatalf("expected tool_use block with leading prose payload, body=%s", rec.Body.String())
+	}
+
+	for _, f := range findClaudeFrames(frames, "message_delta") {
+		delta, _ := f.Payload["delta"].(map[string]any)
+		if delta["stop_reason"] == "tool_use" {
+			return
+		}
+	}
+	t.Fatalf("expected stop_reason=tool_use, body=%s", rec.Body.String())
+}
+
+func TestHandleClaudeStreamRealtimeIgnoresUnclosedFencedToolExample(t *testing.T) {
+	h := &Handler{}
+	resp := makeClaudeSSEHTTPResponse(
+		"data: {\"p\":\"response/content\",\"v\":\"Here is an example:\\n```json\\n{\\\"tool_calls\\\":[{\\\"name\\\":\\\"Bash\\\",\\\"input\\\":{\\\"command\\\":\\\"pwd\\\"}}]}\"}",
+		"data: {\"p\":\"response/content\",\"v\":\"\\n```\\nDo not execute it.\"}",
+		`data: [DONE]`,
+	)
+	rec := httptest.NewRecorder()
+	req := httptest.NewRequest(http.MethodPost, "/anthropic/v1/messages", nil)
+
+	h.handleClaudeStreamRealtime(rec, req, resp, "claude-sonnet-4-5", []any{map[string]any{"role": "user", "content": "show example only"}}, false, false, []string{"Bash"})
+
+	frames := parseClaudeFrames(t, rec.Body.String())
+	foundToolUse := false
+	for _, f := range findClaudeFrames(frames, "content_block_start") {
+		contentBlock, _ := f.Payload["content_block"].(map[string]any)
+		if contentBlock["type"] == "tool_use" {
+			foundToolUse = true
+			break
+		}
+	}
+	if foundToolUse {
+		t.Fatalf("expected no tool_use for fenced example, body=%s", rec.Body.String())
+	}
+
+	foundToolStop := false
+	for _, f := range findClaudeFrames(frames, "message_delta") {
+		delta, _ := f.Payload["delta"].(map[string]any)
+		if delta["stop_reason"] == "tool_use" {
+			foundToolStop = true
+			break
+		}
+	}
+	if foundToolStop {
+		t.Fatalf("expected stop_reason to remain content-only, body=%s", rec.Body.String())
+	}
+}
+
+// Backward-compatible alias for historical test name used in CI logs.
+func TestHandleClaudeStreamRealtimePromotesUnclosedFencedToolExample(t *testing.T) {
+	TestHandleClaudeStreamRealtimeIgnoresUnclosedFencedToolExample(t)
+}

internal/httpapi/claude/handler_tokens.go

@@ -0,0 +1,51 @@
+package claude
+
+import (
+	"encoding/json"
+	"net/http"
+
+	"ds2api/internal/util"
+)
+
+func (h *Handler) CountTokens(w http.ResponseWriter, r *http.Request) {
+	a, err := h.Auth.Determine(r)
+	if err != nil {
+		writeClaudeError(w, http.StatusUnauthorized, err.Error())
+		return
+	}
+	defer h.Auth.Release(a)
+
+	var req map[string]any
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		writeClaudeError(w, http.StatusBadRequest, "invalid json")
+		return
+	}
+	model, _ := req["model"].(string)
+	messages, _ := req["messages"].([]any)
+	if model == "" || len(messages) == 0 {
+		writeClaudeError(w, http.StatusBadRequest, "Request must include 'model' and 'messages'.")
+		return
+	}
+	inputTokens := 0
+	if sys, ok := req["system"].(string); ok {
+		inputTokens += util.EstimateTokens(sys)
+	}
+	for _, item := range messages {
+		msg, ok := item.(map[string]any)
+		if !ok {
+			continue
+		}
+		inputTokens += 2
+		inputTokens += util.EstimateTokens(extractMessageContent(msg["content"]))
+	}
+	if tools, ok := req["tools"].([]any); ok {
+		for _, t := range tools {
+			b, _ := json.Marshal(t)
+			inputTokens += util.EstimateTokens(string(b))
+		}
+	}
+	if inputTokens < 1 {
+		inputTokens = 1
+	}
+	writeJSON(w, http.StatusOK, map[string]any{"input_tokens": inputTokens})
+}

internal/httpapi/claude/handler_util_test.go

@@ -0,0 +1,560 @@
+package claude
+
+import (
+	"strings"
+	"testing"
+)
+
+// ─── normalizeClaudeMessages ─────────────────────────────────────────
+
+func TestNormalizeClaudeMessagesSimpleString(t *testing.T) {
+	msgs := []any{
+		map[string]any{"role": "user", "content": "Hello"},
+	}
+	got := normalizeClaudeMessages(msgs)
+	if len(got) != 1 {
+		t.Fatalf("expected 1 message, got %d", len(got))
+	}
+	m := got[0].(map[string]any)
+	if m["content"] != "Hello" {
+		t.Fatalf("expected 'Hello', got %v", m["content"])
+	}
+}
+
+func TestNormalizeClaudeMessagesArrayContent(t *testing.T) {
+	msgs := []any{
+		map[string]any{
+			"role": "user",
+			"content": []any{
+				map[string]any{"type": "text", "text": "line1"},
+				map[string]any{"type": "text", "text": "line2"},
+			},
+		},
+	}
+	got := normalizeClaudeMessages(msgs)
+	m := got[0].(map[string]any)
+	if m["content"] != "line1\nline2" {
+		t.Fatalf("expected joined text, got %q", m["content"])
+	}
+}
+
+func TestNormalizeClaudeMessagesToolResult(t *testing.T) {
+	msgs := []any{
+		map[string]any{
+			"role": "user",
+			"content": []any{
+				map[string]any{"type": "tool_result", "content": "tool output"},
+			},
+		},
+	}
+	got := normalizeClaudeMessages(msgs)
+	if len(got) != 1 {
+		t.Fatalf("expected one normalized message, got %d", len(got))
+	}
+	m := got[0].(map[string]any)
+	if m["role"] != "tool" {
+		t.Fatalf("expected tool role preserved, got %#v", m["role"])
+	}
+	content, _ := m["content"].(string)
+	if content != "tool output" {
+		t.Fatalf("expected raw tool output content preserved, got %q", content)
+	}
+}
+
+func TestNormalizeClaudeMessagesToolUseToAssistantToolCalls(t *testing.T) {
+	msgs := []any{
+		map[string]any{
+			"role": "assistant",
+			"content": []any{
+				map[string]any{
+					"type":  "tool_use",
+					"id":    "call_1",
+					"name":  "search_web",
+					"input": map[string]any{"query": "latest"},
+				},
+			},
+		},
+	}
+
+	got := normalizeClaudeMessages(msgs)
+	if len(got) != 1 {
+		t.Fatalf("expected one normalized tool-call message, got %d", len(got))
+	}
+	m := got[0].(map[string]any)
+	if m["role"] != "assistant" {
+		t.Fatalf("expected assistant role, got %#v", m["role"])
+	}
+	tc, _ := m["tool_calls"].([]any)
+	if len(tc) != 1 {
+		t.Fatalf("expected one tool call, got %#v", m["tool_calls"])
+	}
+	call, _ := tc[0].(map[string]any)
+	if call["id"] != "call_1" {
+		t.Fatalf("expected call id preserved, got %#v", call)
+	}
+	content, _ := m["content"].(string)
+	if !containsStr(content, "<tool_calls>") || !containsStr(content, `<invoke name="search_web">`) {
+		t.Fatalf("expected assistant content to include XML tool call history, got %q", content)
+	}
+	if !containsStr(content, `<parameter name="query"><![CDATA[latest]]></parameter>`) {
+		t.Fatalf("expected assistant content to include serialized parameters, got %q", content)
+	}
+}
+
+func TestNormalizeClaudeMessagesDoesNotPromoteUserToolUse(t *testing.T) {
+	msgs := []any{
+		map[string]any{
+			"role": "user",
+			"content": []any{
+				map[string]any{
+					"type":  "tool_use",
+					"id":    "call_unsafe",
+					"name":  "dangerous_tool",
+					"input": map[string]any{"value": "x"},
+				},
+			},
+		},
+	}
+
+	got := normalizeClaudeMessages(msgs)
+	if len(got) != 1 {
+		t.Fatalf("expected one normalized message, got %d", len(got))
+	}
+	m := got[0].(map[string]any)
+	if m["role"] != "user" {
+		t.Fatalf("expected user role preserved, got %#v", m["role"])
+	}
+	if _, ok := m["tool_calls"]; ok {
+		t.Fatalf("expected no tool_calls promotion for user message, got %#v", m["tool_calls"])
+	}
+	content, _ := m["content"].(string)
+	if !containsStr(content, `"type":"tool_use"`) || !containsStr(content, "dangerous_tool") {
+		t.Fatalf("expected raw tool_use block preserved in user content, got %q", content)
+	}
+}
+
+func TestNormalizeClaudeMessagesSkipsNonMap(t *testing.T) {
+	msgs := []any{"not a map", 42}
+	got := normalizeClaudeMessages(msgs)
+	if len(got) != 0 {
+		t.Fatalf("expected 0 messages for non-map items, got %d", len(got))
+	}
+}
+
+func TestNormalizeClaudeMessagesEmpty(t *testing.T) {
+	got := normalizeClaudeMessages(nil)
+	if len(got) != 0 {
+		t.Fatalf("expected 0, got %d", len(got))
+	}
+}
+
+func TestNormalizeClaudeMessagesPreservesRole(t *testing.T) {
+	msgs := []any{
+		map[string]any{"role": "assistant", "content": "response"},
+	}
+	got := normalizeClaudeMessages(msgs)
+	m := got[0].(map[string]any)
+	if m["role"] != "assistant" {
+		t.Fatalf("expected 'assistant', got %q", m["role"])
+	}
+}
+
+func TestNormalizeClaudeMessagesMixedContentBlocks(t *testing.T) {
+	msgs := []any{
+		map[string]any{
+			"role": "user",
+			"content": []any{
+				map[string]any{"type": "text", "text": "Hello"},
+				map[string]any{"type": "image", "source": map[string]any{"type": "base64", "data": strings.Repeat("A", 2048)}},
+				map[string]any{"type": "text", "text": "World"},
+			},
+		},
+	}
+	got := normalizeClaudeMessages(msgs)
+	m := got[0].(map[string]any)
+	content, _ := m["content"].(string)
+	if !containsStr(content, "Hello") || !containsStr(content, "World") || !containsStr(content, `"type":"image"`) {
+		t.Fatalf("expected text plus non-text block marker preserved, got %q", content)
+	}
+	if !containsStr(content, omittedBinaryMarker) {
+		t.Fatalf("expected binary payload omitted marker, got %q", content)
+	}
+	if containsStr(content, strings.Repeat("A", 100)) {
+		t.Fatalf("expected raw base64 payload not to be included, got %q", content)
+	}
+}
+
+func TestNormalizeClaudeMessagesToolResultNonTextPayloadStringified(t *testing.T) {
+	msgs := []any{
+		map[string]any{
+			"role": "user",
+			"content": []any{
+				map[string]any{
+					"type":        "tool_result",
+					"tool_use_id": "call_image_1",
+					"name":        "vision_tool",
+					"content": []any{
+						map[string]any{"type": "text", "text": "image analysis"},
+						map[string]any{
+							"type":   "image",
+							"source": map[string]any{"type": "base64", "media_type": "image/png", "data": strings.Repeat("B", 2048)},
+						},
+					},
+				},
+			},
+		},
+	}
+
+	got := normalizeClaudeMessages(msgs)
+	if len(got) != 1 {
+		t.Fatalf("expected one normalized message, got %d", len(got))
+	}
+	m := got[0].(map[string]any)
+	if m["role"] != "tool" {
+		t.Fatalf("expected tool role, got %#v", m["role"])
+	}
+	content, _ := m["content"].(string)
+	if !containsStr(content, `"type":"tool_result"`) || !containsStr(content, `"type":"image"`) {
+		t.Fatalf("expected non-text tool_result payload to be JSON stringified, got %q", content)
+	}
+	if !containsStr(content, omittedBinaryMarker) {
+		t.Fatalf("expected binary data to be sanitized with omitted marker, got %q", content)
+	}
+	if containsStr(content, strings.Repeat("B", 100)) {
+		t.Fatalf("expected raw base64 payload not to be included, got %q", content)
+	}
+}
+
+func TestNormalizeClaudeMessagesBackfillsToolResultCallIDByName(t *testing.T) {
+	msgs := []any{
+		map[string]any{
+			"role": "assistant",
+			"content": []any{
+				map[string]any{
+					"type":  "tool_use",
+					"name":  "search_web",
+					"input": map[string]any{"query": "latest"},
+				},
+			},
+		},
+		map[string]any{
+			"role": "user",
+			"content": []any{
+				map[string]any{
+					"type":    "tool_result",
+					"name":    "search_web",
+					"content": "ok",
+				},
+			},
+		},
+	}
+
+	got := normalizeClaudeMessages(msgs)
+	if len(got) != 2 {
+		t.Fatalf("expected 2 messages, got %#v", got)
+	}
+	assistant, _ := got[0].(map[string]any)
+	tc, _ := assistant["tool_calls"].([]any)
+	call, _ := tc[0].(map[string]any)
+	callID, _ := call["id"].(string)
+	if !strings.HasPrefix(callID, "call_claude_") {
+		t.Fatalf("expected generated call id, got %#v", call)
+	}
+	toolMsg, _ := got[1].(map[string]any)
+	if toolMsg["tool_call_id"] != callID {
+		t.Fatalf("expected tool_result to reuse generated id, got %#v", toolMsg)
+	}
+}
+
+// ─── buildClaudeToolPrompt ───────────────────────────────────────────
+
+func TestBuildClaudeToolPromptSingleTool(t *testing.T) {
+	tools := []any{
+		map[string]any{
+			"name":        "search",
+			"description": "Search the web",
+			"input_schema": map[string]any{
+				"type": "object",
+				"properties": map[string]any{
+					"query": map[string]any{"type": "string"},
+				},
+			},
+		},
+	}
+	prompt := buildClaudeToolPrompt(tools)
+	if prompt == "" {
+		t.Fatal("expected non-empty prompt")
+	}
+	// Should contain tool name and description
+	if !containsStr(prompt, "search") {
+		t.Fatalf("expected 'search' in prompt")
+	}
+	if !containsStr(prompt, "Search the web") {
+		t.Fatalf("expected description in prompt")
+	}
+	if !containsStr(prompt, "<tool_calls>") {
+		t.Fatalf("expected XML tool_calls format in prompt")
+	}
+	if !containsStr(prompt, "TOOL CALL FORMAT") {
+		t.Fatalf("expected tool call format header in prompt")
+	}
+}
+
+func TestBuildClaudeToolPromptMultipleTools(t *testing.T) {
+	tools := []any{
+		map[string]any{"name": "tool1", "description": "desc1"},
+		map[string]any{"name": "tool2", "description": "desc2"},
+	}
+	prompt := buildClaudeToolPrompt(tools)
+	if !containsStr(prompt, "tool1") || !containsStr(prompt, "tool2") {
+		t.Fatalf("expected both tools in prompt")
+	}
+}
+
+func TestBuildClaudeToolPromptSupportsOpenAIStyleFunctionTool(t *testing.T) {
+	tools := []any{
+		map[string]any{
+			"type": "function",
+			"function": map[string]any{
+				"name":        "search",
+				"description": "Search via function tool",
+				"parameters": map[string]any{
+					"type": "object",
+					"properties": map[string]any{
+						"q": map[string]any{"type": "string"},
+					},
+				},
+			},
+		},
+	}
+	prompt := buildClaudeToolPrompt(tools)
+	if !containsStr(prompt, "Tool: search") {
+		t.Fatalf("expected OpenAI-style function tool name in prompt, got: %q", prompt)
+	}
+	if !containsStr(prompt, "Search via function tool") {
+		t.Fatalf("expected OpenAI-style function tool description in prompt, got: %q", prompt)
+	}
+	if !containsStr(prompt, "\"q\"") {
+		t.Fatalf("expected parameters schema serialized in prompt, got: %q", prompt)
+	}
+}
+
+func TestBuildClaudeToolPromptSkipsNonMap(t *testing.T) {
+	tools := []any{"not a map"}
+	prompt := buildClaudeToolPrompt(tools)
+	// No valid tools → empty prompt
+	if prompt != "" {
+		t.Fatalf("expected empty prompt for non-map tools, got: %q", prompt)
+	}
+}
+
+// ─── hasSystemMessage ────────────────────────────────────────────────
+
+func TestHasSystemMessageTrue(t *testing.T) {
+	msgs := []any{
+		map[string]any{"role": "system", "content": "You are a helper"},
+		map[string]any{"role": "user", "content": "Hi"},
+	}
+	if !hasSystemMessage(msgs) {
+		t.Fatal("expected true")
+	}
+}
+
+func TestHasSystemMessageFalse(t *testing.T) {
+	msgs := []any{
+		map[string]any{"role": "user", "content": "Hi"},
+		map[string]any{"role": "assistant", "content": "Hello"},
+	}
+	if hasSystemMessage(msgs) {
+		t.Fatal("expected false")
+	}
+}
+
+func TestHasSystemMessageEmpty(t *testing.T) {
+	if hasSystemMessage(nil) {
+		t.Fatal("expected false for nil")
+	}
+}
+
+func TestHasSystemMessageNonMap(t *testing.T) {
+	msgs := []any{"not a map"}
+	if hasSystemMessage(msgs) {
+		t.Fatal("expected false for non-map")
+	}
+}
+
+// ─── extractClaudeToolNames ──────────────────────────────────────────
+
+func TestExtractClaudeToolNamesSingle(t *testing.T) {
+	tools := []any{
+		map[string]any{"name": "search"},
+	}
+	names := extractClaudeToolNames(tools)
+	if len(names) != 1 || names[0] != "search" {
+		t.Fatalf("expected [search], got %v", names)
+	}
+}
+
+func TestExtractClaudeToolNamesMultiple(t *testing.T) {
+	tools := []any{
+		map[string]any{"name": "search"},
+		map[string]any{"name": "calculate"},
+	}
+	names := extractClaudeToolNames(tools)
+	if len(names) != 2 {
+		t.Fatalf("expected 2 names, got %v", names)
+	}
+}
+
+func TestExtractClaudeToolNamesSkipsEmptyName(t *testing.T) {
+	tools := []any{
+		map[string]any{"name": ""},
+		map[string]any{"name": "valid"},
+	}
+	names := extractClaudeToolNames(tools)
+	if len(names) != 1 || names[0] != "valid" {
+		t.Fatalf("expected [valid], got %v", names)
+	}
+}
+
+func TestExtractClaudeToolNamesSkipsNonMap(t *testing.T) {
+	tools := []any{"not a map", 42}
+	names := extractClaudeToolNames(tools)
+	if len(names) != 0 {
+		t.Fatalf("expected 0, got %v", names)
+	}
+}
+
+func TestExtractClaudeToolNamesNil(t *testing.T) {
+	names := extractClaudeToolNames(nil)
+	if len(names) != 0 {
+		t.Fatalf("expected 0, got %v", names)
+	}
+}
+
+func TestExtractClaudeToolNamesSupportsOpenAIStyleFunctionTool(t *testing.T) {
+	tools := []any{
+		map[string]any{
+			"type": "function",
+			"function": map[string]any{
+				"name": "search",
+			},
+		},
+	}
+	names := extractClaudeToolNames(tools)
+	if len(names) != 1 || names[0] != "search" {
+		t.Fatalf("expected [search], got %v", names)
+	}
+}
+
+// ─── toMessageMaps ───────────────────────────────────────────────────
+
+func TestToMessageMapsNormal(t *testing.T) {
+	input := []any{
+		map[string]any{"role": "user", "content": "Hello"},
+	}
+	got := toMessageMaps(input)
+	if len(got) != 1 {
+		t.Fatalf("expected 1, got %d", len(got))
+	}
+}
+
+func TestToMessageMapsNonSlice(t *testing.T) {
+	got := toMessageMaps("not a slice")
+	if got != nil {
+		t.Fatalf("expected nil, got %v", got)
+	}
+}
+
+func TestToMessageMapsSkipsNonMap(t *testing.T) {
+	input := []any{"string", map[string]any{"role": "user"}, 42}
+	got := toMessageMaps(input)
+	if len(got) != 1 {
+		t.Fatalf("expected 1 map, got %d", len(got))
+	}
+}
+
+func TestToMessageMapsNil(t *testing.T) {
+	got := toMessageMaps(nil)
+	if got != nil {
+		t.Fatalf("expected nil, got %v", got)
+	}
+}
+
+// ─── extractMessageContent ──────────────────────────────────────────
+
+func TestExtractMessageContentString(t *testing.T) {
+	if got := extractMessageContent("hello"); got != "hello" {
+		t.Fatalf("expected 'hello', got %q", got)
+	}
+}
+
+func TestExtractMessageContentArray(t *testing.T) {
+	input := []any{"part1", "part2"}
+	got := extractMessageContent(input)
+	if got != "part1\npart2" {
+		t.Fatalf("expected joined, got %q", got)
+	}
+}
+
+func TestExtractMessageContentOther(t *testing.T) {
+	got := extractMessageContent(42)
+	if got != "42" {
+		t.Fatalf("expected '42', got %q", got)
+	}
+}
+
+func TestExtractMessageContentNil(t *testing.T) {
+	got := extractMessageContent(nil)
+	if got != "<nil>" {
+		t.Fatalf("expected '<nil>', got %q", got)
+	}
+}
+
+// ─── cloneMap ────────────────────────────────────────────────────────
+
+func TestCloneMapBasic(t *testing.T) {
+	original := map[string]any{"a": 1, "b": "hello"}
+	clone := cloneMap(original)
+	original["a"] = 999
+	if clone["a"] != 1 {
+		t.Fatalf("expected 1, got %v", clone["a"])
+	}
+	if clone["b"] != "hello" {
+		t.Fatalf("expected 'hello', got %v", clone["b"])
+	}
+}
+
+func TestCloneMapEmpty(t *testing.T) {
+	clone := cloneMap(map[string]any{})
+	if len(clone) != 0 {
+		t.Fatalf("expected empty, got %v", clone)
+	}
+}
+
+func TestCloneMapNested(t *testing.T) {
+	// cloneMap is shallow, so nested maps share references
+	inner := map[string]any{"key": "value"}
+	original := map[string]any{"nested": inner}
+	clone := cloneMap(original)
+	// Shallow clone means inner is shared
+	inner["key"] = "modified"
+	cloneNested := clone["nested"].(map[string]any)
+	if cloneNested["key"] != "modified" {
+		t.Fatal("expected shallow clone to share nested references")
+	}
+}
+
+// helper
+func containsStr(s, sub string) bool {
+	return len(s) >= len(sub) && (s == sub || len(s) > 0 && findSubstring(s, sub))
+}
+
+func findSubstring(s, sub string) bool {
+	for i := 0; i <= len(s)-len(sub); i++ {
+		if s[i:i+len(sub)] == sub {
+			return true
+		}
+	}
+	return false
+}

internal/httpapi/claude/handler_utils.go

@@ -0,0 +1,226 @@
+package claude
+
+import (
+	"ds2api/internal/toolcall"
+	"encoding/json"
+	"fmt"
+	"strings"
+
+	"ds2api/internal/prompt"
+)
+
+func normalizeClaudeMessages(messages []any) []any {
+	out := make([]any, 0, len(messages))
+	state := &claudeToolCallState{
+		nameByID:       map[string]string{},
+		lastIDByName:   map[string]string{},
+		callIDSequence: 0,
+	}
+	for _, m := range messages {
+		msg, ok := m.(map[string]any)
+		if !ok {
+			continue
+		}
+		role := strings.ToLower(strings.TrimSpace(fmt.Sprintf("%v", msg["role"])))
+		switch content := msg["content"].(type) {
+		case []any:
+			textParts := make([]string, 0, len(content))
+			flushText := func() {
+				if len(textParts) == 0 {
+					return
+				}
+				out = append(out, map[string]any{
+					"role":    role,
+					"content": strings.Join(textParts, "\n"),
+				})
+				textParts = textParts[:0]
+			}
+			for _, block := range content {
+				b, ok := block.(map[string]any)
+				if !ok {
+					continue
+				}
+				typeStr := strings.ToLower(strings.TrimSpace(fmt.Sprintf("%v", b["type"])))
+				switch typeStr {
+				case "text":
+					if t, ok := b["text"].(string); ok {
+						textParts = append(textParts, t)
+					}
+				case "tool_use":
+					if role == "assistant" {
+						flushText()
+						if toolMsg := normalizeClaudeToolUseToAssistant(b, state); toolMsg != nil {
+							out = append(out, toolMsg)
+						}
+						continue
+					}
+					if raw := strings.TrimSpace(formatClaudeUnknownBlockForPrompt(b)); raw != "" {
+						textParts = append(textParts, raw)
+					}
+				case "tool_result":
+					flushText()
+					if toolMsg := normalizeClaudeToolResultToToolMessage(b, state); toolMsg != nil {
+						out = append(out, toolMsg)
+					}
+				default:
+					if raw := strings.TrimSpace(formatClaudeUnknownBlockForPrompt(b)); raw != "" {
+						textParts = append(textParts, raw)
+					}
+				}
+			}
+			flushText()
+		default:
+			copied := cloneMap(msg)
+			out = append(out, copied)
+		}
+	}
+	return out
+}
+
+func buildClaudeToolPrompt(tools []any) string {
+	toolSchemas := make([]string, 0, len(tools))
+	names := make([]string, 0, len(tools))
+	for _, t := range tools {
+		m, ok := t.(map[string]any)
+		if !ok {
+			continue
+		}
+		name, desc, schemaObj := extractClaudeToolMeta(m)
+		if name == "" {
+			continue
+		}
+		names = append(names, name)
+		schema, _ := json.Marshal(schemaObj)
+		toolSchemas = append(toolSchemas, fmt.Sprintf("Tool: %s\nDescription: %s\nParameters: %s", name, desc, schema))
+	}
+	if len(toolSchemas) == 0 {
+		return ""
+	}
+	return "You have access to these tools:\n\n" +
+		strings.Join(toolSchemas, "\n\n") + "\n\n" +
+		toolcall.BuildToolCallInstructions(names)
+}
+
+//nolint:unused // retained for compatibility with pending Claude tool-result prompt flow.
+func formatClaudeToolResultForPrompt(block map[string]any) string {
+	if block == nil {
+		return ""
+	}
+	payload := map[string]any{
+		"type":    "tool_result",
+		"content": block["content"],
+	}
+	if toolCallID := strings.TrimSpace(fmt.Sprintf("%v", block["tool_use_id"])); toolCallID != "" {
+		payload["tool_call_id"] = toolCallID
+	} else if toolCallID := strings.TrimSpace(fmt.Sprintf("%v", block["tool_call_id"])); toolCallID != "" {
+		payload["tool_call_id"] = toolCallID
+	}
+	if name := strings.TrimSpace(fmt.Sprintf("%v", block["name"])); name != "" {
+		payload["name"] = name
+	}
+	b, err := json.Marshal(payload)
+	if err != nil {
+		return strings.TrimSpace(fmt.Sprintf("%v", payload))
+	}
+	return string(b)
+}
+
+func normalizeClaudeToolUseToAssistant(block map[string]any, state *claudeToolCallState) map[string]any {
+	if block == nil {
+		return nil
+	}
+	name := strings.TrimSpace(fmt.Sprintf("%v", block["name"]))
+	if name == "" {
+		return nil
+	}
+	callID := safeStringValue(block["id"])
+	if callID == "" {
+		callID = safeStringValue(block["tool_use_id"])
+	}
+	if callID == "" {
+		callID = state.nextID()
+	}
+	state.nameByID[callID] = name
+	state.lastIDByName[strings.ToLower(name)] = callID
+	arguments := block["input"]
+	if arguments == nil {
+		arguments = map[string]any{}
+	}
+	argsJSON, err := json.Marshal(arguments)
+	if err != nil || len(argsJSON) == 0 {
+		argsJSON = []byte("{}")
+	}
+	toolCalls := []any{
+		map[string]any{
+			"id":   callID,
+			"type": "function",
+			"function": map[string]any{
+				"name":      name,
+				"arguments": string(argsJSON),
+			},
+		},
+	}
+	return map[string]any{
+		"role":       "assistant",
+		"content":    prompt.FormatToolCallsForPrompt(toolCalls),
+		"tool_calls": toolCalls,
+	}
+}
+
+func normalizeClaudeToolResultToToolMessage(block map[string]any, state *claudeToolCallState) map[string]any {
+	if block == nil {
+		return nil
+	}
+	name := safeStringValue(block["name"])
+	toolCallID := safeStringValue(block["tool_use_id"])
+	if toolCallID == "" {
+		toolCallID = safeStringValue(block["tool_call_id"])
+	}
+	if toolCallID == "" {
+		if name != "" {
+			toolCallID = strings.TrimSpace(state.lastIDByName[strings.ToLower(name)])
+		}
+	}
+	if toolCallID == "" {
+		toolCallID = state.nextID()
+	}
+	out := map[string]any{
+		"role":         "tool",
+		"tool_call_id": toolCallID,
+		"content":      normalizeClaudeToolResultContent(block["content"]),
+	}
+	if name != "" {
+		out["name"] = name
+		state.nameByID[toolCallID] = name
+		state.lastIDByName[strings.ToLower(name)] = toolCallID
+	} else if inferred := strings.TrimSpace(state.nameByID[toolCallID]); inferred != "" {
+		out["name"] = inferred
+	}
+	return out
+}
+
+func normalizeClaudeToolResultContent(content any) any {
+	if text, ok := content.(string); ok {
+		return text
+	}
+	payload := map[string]any{
+		"type":    "tool_result",
+		"content": content,
+	}
+	b, err := json.Marshal(sanitizeClaudeBlockForPrompt(payload))
+	if err != nil {
+		return strings.TrimSpace(fmt.Sprintf("%v", content))
+	}
+	return string(b)
+}
+
+func formatClaudeBlockRaw(block map[string]any) string {
+	if block == nil {
+		return ""
+	}
+	b, err := json.Marshal(block)
+	if err != nil {
+		return strings.TrimSpace(fmt.Sprintf("%v", block))
+	}
+	return string(b)
+}

internal/httpapi/claude/handler_utils_sanitize.go

@@ -0,0 +1,106 @@
+package claude
+
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+)
+
+const (
+	maxClaudeRawPromptChars = 1024
+	omittedBinaryMarker     = "[omitted_binary_payload]"
+)
+
+func formatClaudeUnknownBlockForPrompt(block map[string]any) string {
+	if block == nil {
+		return ""
+	}
+	safe := sanitizeClaudeBlockForPrompt(block)
+	raw := strings.TrimSpace(formatClaudeBlockRaw(safe))
+	if raw == "" {
+		return ""
+	}
+	if len(raw) > maxClaudeRawPromptChars {
+		return raw[:maxClaudeRawPromptChars] + "...(truncated)"
+	}
+	return raw
+}
+
+func sanitizeClaudeBlockForPrompt(block map[string]any) map[string]any {
+	out := cloneMap(block)
+	for k, v := range out {
+		if looksLikeBinaryFieldName(k) {
+			out[k] = omittedBinaryMarker
+			continue
+		}
+		switch inner := v.(type) {
+		case map[string]any:
+			out[k] = sanitizeClaudeBlockForPrompt(inner)
+		case []any:
+			out[k] = sanitizeClaudeArrayForPrompt(inner)
+		case string:
+			out[k] = sanitizeClaudeStringForPrompt(k, inner)
+		}
+	}
+	return out
+}
+
+func sanitizeClaudeArrayForPrompt(items []any) []any {
+	out := make([]any, 0, len(items))
+	for _, item := range items {
+		switch v := item.(type) {
+		case map[string]any:
+			out = append(out, sanitizeClaudeBlockForPrompt(v))
+		case []any:
+			out = append(out, sanitizeClaudeArrayForPrompt(v))
+		default:
+			out = append(out, v)
+		}
+	}
+	return out
+}
+
+func sanitizeClaudeStringForPrompt(key, value string) string {
+	trimmed := strings.TrimSpace(value)
+	if trimmed == "" {
+		return ""
+	}
+	if looksLikeBinaryFieldName(key) || looksLikeBase64Payload(trimmed) {
+		return omittedBinaryMarker
+	}
+	if len(trimmed) > maxClaudeRawPromptChars {
+		return trimmed[:maxClaudeRawPromptChars] + "...(truncated)"
+	}
+	return trimmed
+}
+
+func looksLikeBinaryFieldName(name string) bool {
+	n := strings.ToLower(strings.TrimSpace(name))
+	return n == "data" || n == "bytes" || n == "base64" || n == "inline_data" || n == "inlinedata"
+}
+
+func looksLikeBase64Payload(v string) bool {
+	if len(v) < 512 {
+		return false
+	}
+	compact := strings.TrimRight(v, "=")
+	if compact == "" {
+		return false
+	}
+	for _, ch := range compact {
+		if (ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z') || (ch >= '0' && ch <= '9') || ch == '+' || ch == '/' || ch == '-' || ch == '_' {
+			continue
+		}
+		return false
+	}
+	return true
+}
+
+//nolint:unused // helper kept for compatibility with upcoming sanitize pipeline.
+func marshalCompactJSON(v any) string {
+	b, err := json.Marshal(v)
+	if err != nil {
+		return strings.TrimSpace(fmt.Sprintf("%v", v))
+	}
+	return string(b)
+}

internal/httpapi/claude/output_clean.go

@@ -0,0 +1,13 @@
+package claude
+
+import textclean "ds2api/internal/textclean"
+
+func cleanVisibleOutput(text string, stripReferenceMarkers bool) string {
+	if text == "" {
+		return text
+	}
+	if stripReferenceMarkers {
+		text = textclean.StripReferenceMarkers(text)
+	}
+	return text
+}

internal/httpapi/claude/proxy_vercel_test.go

@@ -0,0 +1,197 @@
+package claude
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+)
+
+type claudeProxyStoreStub struct {
+	aliases map[string]string
+}
+
+func (s claudeProxyStoreStub) ModelAliases() map[string]string { return s.aliases }
+
+func (claudeProxyStoreStub) CompatStripReferenceMarkers() bool { return true }
+
+type openAIProxyStub struct {
+	status int
+	body   string
+}
+
+func TestClaudeProxyViaOpenAIPrefersGlobalAliasMapping(t *testing.T) {
+	openAI := &openAIProxyCaptureStub{}
+	h := &Handler{
+		Store: claudeProxyStoreStub{
+			aliases: map[string]string{"claude-sonnet-4-6": "deepseek-v4-flash"},
+		},
+		OpenAI: openAI,
+	}
+	req := httptest.NewRequest(http.MethodPost, "/anthropic/v1/messages", strings.NewReader(`{"model":"claude-sonnet-4-6","messages":[{"role":"user","content":"hi"}],"stream":false}`))
+	rec := httptest.NewRecorder()
+
+	h.Messages(rec, req)
+
+	if rec.Code != http.StatusOK {
+		t.Fatalf("unexpected status: %d body=%s", rec.Code, rec.Body.String())
+	}
+	if got := strings.TrimSpace(openAI.seenModel); got != "deepseek-v4-flash" {
+		t.Fatalf("expected global alias mapped proxy model deepseek-v4-flash, got %q", got)
+	}
+}
+
+func (s openAIProxyStub) ChatCompletions(w http.ResponseWriter, _ *http.Request) {
+	if s.status == 0 {
+		s.status = http.StatusOK
+	}
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(s.status)
+	_, _ = w.Write([]byte(s.body))
+}
+
+type openAIProxyCaptureStub struct {
+	seenModel string
+	seenReq   map[string]any
+}
+
+func (s *openAIProxyCaptureStub) ChatCompletions(w http.ResponseWriter, r *http.Request) {
+	var req map[string]any
+	_ = json.NewDecoder(r.Body).Decode(&req)
+	s.seenReq = req
+	if m, ok := req["model"].(string); ok {
+		s.seenModel = m
+	}
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(http.StatusOK)
+	_, _ = w.Write([]byte(`{"id":"ok","choices":[{"message":{"role":"assistant","content":"ok"}}]}`))
+}
+
+func TestClaudeProxyViaOpenAIVercelPreparePassthrough(t *testing.T) {
+	h := &Handler{OpenAI: openAIProxyStub{status: 200, body: `{"lease_id":"lease_123","payload":{"a":1}}`}}
+	req := httptest.NewRequest(http.MethodPost, "/anthropic/v1/messages?__stream_prepare=1", strings.NewReader(`{"model":"claude-sonnet-4-5","messages":[{"role":"user","content":"hi"}],"stream":true}`))
+	rec := httptest.NewRecorder()
+
+	h.Messages(rec, req)
+
+	if rec.Code != http.StatusOK {
+		t.Fatalf("unexpected status: %d body=%s", rec.Code, rec.Body.String())
+	}
+	var out map[string]any
+	if err := json.Unmarshal(rec.Body.Bytes(), &out); err != nil {
+		t.Fatalf("expected json response, got err=%v body=%s", err, rec.Body.String())
+	}
+	if _, ok := out["lease_id"]; !ok {
+		t.Fatalf("expected lease_id in prepare passthrough, got=%v", out)
+	}
+}
+
+func TestClaudeProxyViaOpenAIUsesGlobalAliasMapping(t *testing.T) {
+	openAI := &openAIProxyCaptureStub{}
+	h := &Handler{
+		Store:  claudeProxyStoreStub{aliases: map[string]string{"claude-3-opus": "deepseek-v4-pro"}},
+		OpenAI: openAI,
+	}
+	req := httptest.NewRequest(http.MethodPost, "/anthropic/v1/messages", strings.NewReader(`{"model":"claude-3-opus","messages":[{"role":"user","content":"hi"}],"stream":false}`))
+	rec := httptest.NewRecorder()
+
+	h.Messages(rec, req)
+
+	if rec.Code != http.StatusOK {
+		t.Fatalf("unexpected status: %d body=%s", rec.Code, rec.Body.String())
+	}
+	if got := strings.TrimSpace(openAI.seenModel); got != "deepseek-v4-pro" {
+		t.Fatalf("expected mapped proxy model deepseek-v4-pro, got %q", got)
+	}
+}
+
+func TestClaudeProxyViaOpenAIPreservesThinkingOverride(t *testing.T) {
+	openAI := &openAIProxyCaptureStub{}
+	h := &Handler{
+		Store:  claudeProxyStoreStub{aliases: map[string]string{"claude-sonnet-4-6": "deepseek-v4-flash"}},
+		OpenAI: openAI,
+	}
+	req := httptest.NewRequest(http.MethodPost, "/anthropic/v1/messages", strings.NewReader(`{"model":"claude-sonnet-4-6","messages":[{"role":"user","content":"hi"}],"thinking":{"type":"disabled"},"stream":false}`))
+	rec := httptest.NewRecorder()
+
+	h.Messages(rec, req)
+
+	if rec.Code != http.StatusOK {
+		t.Fatalf("unexpected status: %d body=%s", rec.Code, rec.Body.String())
+	}
+	thinking, _ := openAI.seenReq["thinking"].(map[string]any)
+	if thinking["type"] != "disabled" {
+		t.Fatalf("expected translated OpenAI request to preserve disabled thinking, got %#v", openAI.seenReq)
+	}
+}
+
+func TestClaudeProxyViaOpenAIDisablesThinkingByDefault(t *testing.T) {
+	openAI := &openAIProxyCaptureStub{}
+	h := &Handler{
+		Store:  claudeProxyStoreStub{aliases: map[string]string{"claude-sonnet-4-6": "deepseek-v4-flash"}},
+		OpenAI: openAI,
+	}
+	req := httptest.NewRequest(http.MethodPost, "/anthropic/v1/messages", strings.NewReader(`{"model":"claude-sonnet-4-6","messages":[{"role":"user","content":"hi"}],"stream":false}`))
+	rec := httptest.NewRecorder()
+
+	h.Messages(rec, req)
+
+	if rec.Code != http.StatusOK {
+		t.Fatalf("unexpected status: %d body=%s", rec.Code, rec.Body.String())
+	}
+	thinking, _ := openAI.seenReq["thinking"].(map[string]any)
+	if thinking["type"] != "disabled" {
+		t.Fatalf("expected Claude default to disable downstream thinking, got %#v", openAI.seenReq)
+	}
+}
+
+func TestClaudeProxyViaOpenAIEnablesThinkingWhenRequested(t *testing.T) {
+	openAI := &openAIProxyCaptureStub{}
+	h := &Handler{
+		Store:  claudeProxyStoreStub{aliases: map[string]string{"claude-sonnet-4-6": "deepseek-v4-flash"}},
+		OpenAI: openAI,
+	}
+	req := httptest.NewRequest(http.MethodPost, "/anthropic/v1/messages", strings.NewReader(`{"model":"claude-sonnet-4-6","messages":[{"role":"user","content":"hi"}],"thinking":{"type":"enabled","budget_tokens":1024},"stream":false}`))
+	rec := httptest.NewRecorder()
+
+	h.Messages(rec, req)
+
+	if rec.Code != http.StatusOK {
+		t.Fatalf("unexpected status: %d body=%s", rec.Code, rec.Body.String())
+	}
+	thinking, _ := openAI.seenReq["thinking"].(map[string]any)
+	if thinking["type"] != "enabled" {
+		t.Fatalf("expected Claude explicit thinking to enable downstream thinking, got %#v", openAI.seenReq)
+	}
+}
+
+func TestClaudeProxyTranslatesInlineImageToOpenAIDataURL(t *testing.T) {
+	openAI := &openAIProxyCaptureStub{}
+	h := &Handler{OpenAI: openAI}
+	req := httptest.NewRequest(http.MethodPost, "/anthropic/v1/messages", strings.NewReader(`{"model":"claude-sonnet-4-5","messages":[{"role":"user","content":[{"type":"text","text":"hello"},{"type":"image","source":{"type":"base64","media_type":"image/png","data":"QUJDRA=="}}]}],"stream":false}`))
+	rec := httptest.NewRecorder()
+
+	h.Messages(rec, req)
+
+	if rec.Code != http.StatusOK {
+		t.Fatalf("unexpected status: %d body=%s", rec.Code, rec.Body.String())
+	}
+	messages, _ := openAI.seenReq["messages"].([]any)
+	if len(messages) != 1 {
+		t.Fatalf("expected one translated message, got %#v", openAI.seenReq)
+	}
+	msg, _ := messages[0].(map[string]any)
+	content, _ := msg["content"].([]any)
+	if len(content) != 2 {
+		t.Fatalf("expected translated content blocks, got %#v", msg)
+	}
+	imageBlock, _ := content[1].(map[string]any)
+	if strings.TrimSpace(asString(imageBlock["type"])) != "image_url" {
+		t.Fatalf("expected image_url block, got %#v", imageBlock)
+	}
+	imageURL, _ := imageBlock["image_url"].(map[string]any)
+	if !strings.HasPrefix(strings.TrimSpace(asString(imageURL["url"])), "data:image/png;base64,") {
+		t.Fatalf("expected translated data url, got %#v", imageBlock)
+	}
+}

internal/httpapi/claude/route_alias_test.go

@@ -0,0 +1,44 @@
+package claude
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/go-chi/chi/v5"
+
+	"ds2api/internal/auth"
+)
+
+type routeAliasAuthStub struct{}
+
+func (routeAliasAuthStub) Determine(_ *http.Request) (*auth.RequestAuth, error) {
+	return nil, auth.ErrUnauthorized
+}
+
+func (routeAliasAuthStub) Release(_ *auth.RequestAuth) {}
+
+func TestClaudeRouteAliasesDoNot404(t *testing.T) {
+	h := &Handler{
+		Auth: routeAliasAuthStub{},
+	}
+	r := chi.NewRouter()
+	RegisterRoutes(r, h)
+
+	paths := []string{
+		"/anthropic/v1/messages",
+		"/v1/messages",
+		"/messages",
+		"/anthropic/v1/messages/count_tokens",
+		"/v1/messages/count_tokens",
+		"/messages/count_tokens",
+	}
+	for _, path := range paths {
+		req := httptest.NewRequest(http.MethodPost, path, nil)
+		rec := httptest.NewRecorder()
+		r.ServeHTTP(rec, req)
+		if rec.Code == http.StatusNotFound {
+			t.Fatalf("expected route %s to be registered, got 404", path)
+		}
+	}
+}

internal/httpapi/claude/standard_request.go

@@ -0,0 +1,117 @@
+package claude
+
+import (
+	"fmt"
+	"strings"
+
+	"ds2api/internal/config"
+	"ds2api/internal/prompt"
+	"ds2api/internal/promptcompat"
+	"ds2api/internal/util"
+)
+
+type claudeNormalizedRequest struct {
+	Standard           promptcompat.StandardRequest
+	NormalizedMessages []any
+}
+
+func normalizeClaudeRequest(store ConfigReader, req map[string]any) (claudeNormalizedRequest, error) {
+	model, _ := req["model"].(string)
+	messagesRaw, _ := req["messages"].([]any)
+	if strings.TrimSpace(model) == "" || len(messagesRaw) == 0 {
+		return claudeNormalizedRequest{}, fmt.Errorf("request must include 'model' and 'messages'")
+	}
+	if _, ok := req["max_tokens"]; !ok {
+		req["max_tokens"] = 8192
+	}
+	normalizedMessages := normalizeClaudeMessages(messagesRaw)
+	payload := cloneMap(req)
+	payload["messages"] = normalizedMessages
+	toolsRequested, _ := req["tools"].([]any)
+	payload["messages"] = injectClaudeToolPrompt(payload, normalizedMessages, toolsRequested)
+
+	dsPayload := convertClaudeToDeepSeek(payload, store)
+	dsModel, _ := dsPayload["model"].(string)
+	_, searchEnabled, ok := config.GetModelConfig(dsModel)
+	if !ok {
+		searchEnabled = false
+	}
+	thinkingEnabled := util.ResolveThinkingEnabled(req, false)
+	finalPrompt := prompt.MessagesPrepareWithThinking(toMessageMaps(dsPayload["messages"]), thinkingEnabled)
+	toolNames := extractClaudeToolNames(toolsRequested)
+	if len(toolNames) == 0 && len(toolsRequested) > 0 {
+		toolNames = []string{"__any_tool__"}
+	}
+
+	return claudeNormalizedRequest{
+		Standard: promptcompat.StandardRequest{
+			Surface:        "anthropic_messages",
+			RequestedModel: strings.TrimSpace(model),
+			ResolvedModel:  dsModel,
+			ResponseModel:  strings.TrimSpace(model),
+			Messages:       payload["messages"].([]any),
+			FinalPrompt:    finalPrompt,
+			ToolNames:      toolNames,
+			Stream:         util.ToBool(req["stream"]),
+			Thinking:       thinkingEnabled,
+			Search:         searchEnabled,
+		},
+		NormalizedMessages: normalizedMessages,
+	}, nil
+}
+
+func injectClaudeToolPrompt(payload map[string]any, normalizedMessages []any, tools []any) []any {
+	if len(tools) == 0 {
+		return normalizedMessages
+	}
+	toolPrompt := strings.TrimSpace(buildClaudeToolPrompt(tools))
+	if toolPrompt == "" {
+		return normalizedMessages
+	}
+
+	// Prefer top-level Anthropic-style system prompt when available.
+	if systemText, ok := payload["system"].(string); ok && strings.TrimSpace(systemText) != "" {
+		payload["system"] = mergeSystemPrompt(systemText, toolPrompt)
+		return normalizedMessages
+	}
+
+	messages := cloneAnySlice(normalizedMessages)
+	for i := range messages {
+		msg, ok := messages[i].(map[string]any)
+		if !ok {
+			continue
+		}
+		role, _ := msg["role"].(string)
+		if !strings.EqualFold(strings.TrimSpace(role), "system") {
+			continue
+		}
+		copied := cloneMap(msg)
+		copied["content"] = mergeSystemPrompt(strings.TrimSpace(fmt.Sprintf("%v", copied["content"])), toolPrompt)
+		messages[i] = copied
+		return messages
+	}
+
+	return append([]any{map[string]any{"role": "system", "content": toolPrompt}}, messages...)
+}
+
+func mergeSystemPrompt(base, extra string) string {
+	base = strings.TrimSpace(base)
+	extra = strings.TrimSpace(extra)
+	switch {
+	case base == "":
+		return extra
+	case extra == "":
+		return base
+	default:
+		return base + "\n\n" + extra
+	}
+}
+
+func cloneAnySlice(in []any) []any {
+	if len(in) == 0 {
+		return nil
+	}
+	out := make([]any, len(in))
+	copy(out, in)
+	return out
+}

internal/httpapi/claude/standard_request_test.go

@@ -0,0 +1,92 @@
+package claude
+
+import (
+	"testing"
+
+	"ds2api/internal/config"
+)
+
+func TestNormalizeClaudeRequest(t *testing.T) {
+	t.Setenv("DS2API_CONFIG_JSON", `{}`)
+	store := config.LoadStore()
+	req := map[string]any{
+		"model": "claude-opus-4-6",
+		"messages": []any{
+			map[string]any{"role": "user", "content": "hello"},
+		},
+		"stream": true,
+		"tools": []any{
+			map[string]any{"name": "search", "description": "Search"},
+		},
+	}
+	norm, err := normalizeClaudeRequest(store, req)
+	if err != nil {
+		t.Fatalf("normalize failed: %v", err)
+	}
+	if norm.Standard.ResolvedModel == "" {
+		t.Fatalf("expected resolved model")
+	}
+	if !norm.Standard.Stream {
+		t.Fatalf("expected stream=true")
+	}
+	if len(norm.Standard.ToolNames) == 0 {
+		t.Fatalf("expected tool names")
+	}
+	if norm.Standard.FinalPrompt == "" {
+		t.Fatalf("expected non-empty final prompt")
+	}
+}
+
+func TestNormalizeClaudeRequestInjectsToolsIntoExistingSystemMessage(t *testing.T) {
+	t.Setenv("DS2API_CONFIG_JSON", `{}`)
+	store := config.LoadStore()
+	req := map[string]any{
+		"model": "claude-sonnet-4-5",
+		"messages": []any{
+			map[string]any{"role": "system", "content": "baseline rule"},
+			map[string]any{"role": "user", "content": "hello"},
+		},
+		"tools": []any{
+			map[string]any{"name": "search", "description": "Search"},
+		},
+	}
+
+	norm, err := normalizeClaudeRequest(store, req)
+	if err != nil {
+		t.Fatalf("normalize failed: %v", err)
+	}
+
+	if !containsStr(norm.Standard.FinalPrompt, "You have access to these tools") {
+		t.Fatalf("expected tool prompt injected into final prompt, got=%q", norm.Standard.FinalPrompt)
+	}
+	if !containsStr(norm.Standard.FinalPrompt, "baseline rule") {
+		t.Fatalf("expected existing system message preserved, got=%q", norm.Standard.FinalPrompt)
+	}
+}
+
+func TestNormalizeClaudeRequestInjectsToolsIntoTopLevelSystem(t *testing.T) {
+	t.Setenv("DS2API_CONFIG_JSON", `{}`)
+	store := config.LoadStore()
+	req := map[string]any{
+		"model":  "claude-sonnet-4-5",
+		"system": "top-level system",
+		"messages": []any{
+			map[string]any{"role": "user", "content": "hello"},
+		},
+		"tools": []any{
+			map[string]any{"name": "search", "description": "Search"},
+		},
+	}
+
+	norm, err := normalizeClaudeRequest(store, req)
+	if err != nil {
+		t.Fatalf("normalize failed: %v", err)
+	}
+
+	if !containsStr(norm.Standard.FinalPrompt, "top-level system") {
+		t.Fatalf("expected top-level system preserved, got=%q", norm.Standard.FinalPrompt)
+	}
+	if !containsStr(norm.Standard.FinalPrompt, "You have access to these tools") {
+		t.Fatalf("expected tool prompt injected, got=%q", norm.Standard.FinalPrompt)
+	}
+}

internal/httpapi/claude/stream_runtime_core.go

@@ -0,0 +1,165 @@
+package claude
+
+import (
+	"fmt"
+	"net/http"
+	"strings"
+	"time"
+
+	"ds2api/internal/sse"
+	streamengine "ds2api/internal/stream"
+)
+
+type claudeStreamRuntime struct {
+	w        http.ResponseWriter
+	rc       *http.ResponseController
+	canFlush bool
+
+	model     string
+	toolNames []string
+	messages  []any
+
+	thinkingEnabled       bool
+	searchEnabled         bool
+	bufferToolContent     bool
+	stripReferenceMarkers bool
+
+	messageID string
+	thinking  strings.Builder
+	text      strings.Builder
+
+	nextBlockIndex     int
+	thinkingBlockOpen  bool
+	thinkingBlockIndex int
+	textBlockOpen      bool
+	textBlockIndex     int
+	ended              bool
+	upstreamErr        string
+}
+
+func newClaudeStreamRuntime(
+	w http.ResponseWriter,
+	rc *http.ResponseController,
+	canFlush bool,
+	model string,
+	messages []any,
+	thinkingEnabled bool,
+	searchEnabled bool,
+	stripReferenceMarkers bool,
+	toolNames []string,
+) *claudeStreamRuntime {
+	return &claudeStreamRuntime{
+		w:                     w,
+		rc:                    rc,
+		canFlush:              canFlush,
+		model:                 model,
+		messages:              messages,
+		thinkingEnabled:       thinkingEnabled,
+		searchEnabled:         searchEnabled,
+		bufferToolContent:     len(toolNames) > 0,
+		stripReferenceMarkers: stripReferenceMarkers,
+		toolNames:             toolNames,
+		messageID:             fmt.Sprintf("msg_%d", time.Now().UnixNano()),
+		thinkingBlockIndex:    -1,
+		textBlockIndex:        -1,
+	}
+}
+
+func (s *claudeStreamRuntime) onParsed(parsed sse.LineResult) streamengine.ParsedDecision {
+	if !parsed.Parsed {
+		return streamengine.ParsedDecision{}
+	}
+	if parsed.ErrorMessage != "" {
+		s.upstreamErr = parsed.ErrorMessage
+		return streamengine.ParsedDecision{Stop: true, StopReason: streamengine.StopReason("upstream_error")}
+	}
+	if parsed.Stop {
+		return streamengine.ParsedDecision{Stop: true}
+	}
+
+	contentSeen := false
+	for _, p := range parsed.Parts {
+		cleanedText := cleanVisibleOutput(p.Text, s.stripReferenceMarkers)
+		if cleanedText == "" {
+			continue
+		}
+		if p.Type != "thinking" && s.searchEnabled && sse.IsCitation(cleanedText) {
+			continue
+		}
+		contentSeen = true
+
+		if p.Type == "thinking" {
+			if !s.thinkingEnabled {
+				continue
+			}
+			trimmed := sse.TrimContinuationOverlap(s.thinking.String(), cleanedText)
+			if trimmed == "" {
+				continue
+			}
+			s.thinking.WriteString(trimmed)
+			s.closeTextBlock()
+			if !s.thinkingBlockOpen {
+				s.thinkingBlockIndex = s.nextBlockIndex
+				s.nextBlockIndex++
+				s.send("content_block_start", map[string]any{
+					"type":  "content_block_start",
+					"index": s.thinkingBlockIndex,
+					"content_block": map[string]any{
+						"type":     "thinking",
+						"thinking": "",
+					},
+				})
+				s.thinkingBlockOpen = true
+			}
+			s.send("content_block_delta", map[string]any{
+				"type":  "content_block_delta",
+				"index": s.thinkingBlockIndex,
+				"delta": map[string]any{
+					"type":     "thinking_delta",
+					"thinking": trimmed,
+				},
+			})
+			continue
+		}
+
+		trimmed := sse.TrimContinuationOverlap(s.text.String(), cleanedText)
+		if trimmed == "" {
+			continue
+		}
+		s.text.WriteString(trimmed)
+		if s.bufferToolContent {
+			if hasUnclosedCodeFence(s.text.String()) {
+				continue
+			}
+			continue
+		}
+		s.closeThinkingBlock()
+		if !s.textBlockOpen {
+			s.textBlockIndex = s.nextBlockIndex
+			s.nextBlockIndex++
+			s.send("content_block_start", map[string]any{
+				"type":  "content_block_start",
+				"index": s.textBlockIndex,
+				"content_block": map[string]any{
+					"type": "text",
+					"text": "",
+				},
+			})
+			s.textBlockOpen = true
+		}
+		s.send("content_block_delta", map[string]any{
+			"type":  "content_block_delta",
+			"index": s.textBlockIndex,
+			"delta": map[string]any{
+				"type": "text_delta",
+				"text": trimmed,
+			},
+		})
+	}
+
+	return streamengine.ParsedDecision{ContentSeen: contentSeen}
+}
+
+func hasUnclosedCodeFence(text string) bool {
+	return strings.Count(text, "```")%2 == 1
+}

internal/httpapi/claude/stream_runtime_emit.go

@@ -0,0 +1,59 @@
+package claude
+
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+
+	"ds2api/internal/util"
+)
+
+func (s *claudeStreamRuntime) send(event string, v any) {
+	b, _ := json.Marshal(v)
+	_, _ = s.w.Write([]byte("event: "))
+	_, _ = s.w.Write([]byte(event))
+	_, _ = s.w.Write([]byte("\n"))
+	_, _ = s.w.Write([]byte("data: "))
+	_, _ = s.w.Write(b)
+	_, _ = s.w.Write([]byte("\n\n"))
+	if s.canFlush {
+		_ = s.rc.Flush()
+	}
+}
+
+func (s *claudeStreamRuntime) sendError(message string) {
+	msg := strings.TrimSpace(message)
+	if msg == "" {
+		msg = "upstream stream error"
+	}
+	s.send("error", map[string]any{
+		"type": "error",
+		"error": map[string]any{
+			"type":    "api_error",
+			"message": msg,
+			"code":    "internal_error",
+			"param":   nil,
+		},
+	})
+}
+
+func (s *claudeStreamRuntime) sendPing() {
+	s.send("ping", map[string]any{"type": "ping"})
+}
+
+func (s *claudeStreamRuntime) sendMessageStart() {
+	inputTokens := util.EstimateTokens(fmt.Sprintf("%v", s.messages))
+	s.send("message_start", map[string]any{
+		"type": "message_start",
+		"message": map[string]any{
+			"id":            s.messageID,
+			"type":          "message",
+			"role":          "assistant",
+			"model":         s.model,
+			"content":       []any{},
+			"stop_reason":   nil,
+			"stop_sequence": nil,
+			"usage":         map[string]any{"input_tokens": inputTokens, "output_tokens": 0},
+		},
+	})
+}

internal/httpapi/claude/stream_runtime_finalize.go

@@ -0,0 +1,135 @@
+package claude
+
+import (
+	"ds2api/internal/toolcall"
+	"encoding/json"
+	"fmt"
+	"time"
+
+	streamengine "ds2api/internal/stream"
+	"ds2api/internal/util"
+)
+
+func (s *claudeStreamRuntime) closeThinkingBlock() {
+	if !s.thinkingBlockOpen {
+		return
+	}
+	s.send("content_block_stop", map[string]any{
+		"type":  "content_block_stop",
+		"index": s.thinkingBlockIndex,
+	})
+	s.thinkingBlockOpen = false
+	s.thinkingBlockIndex = -1
+}
+
+func (s *claudeStreamRuntime) closeTextBlock() {
+	if !s.textBlockOpen {
+		return
+	}
+	s.send("content_block_stop", map[string]any{
+		"type":  "content_block_stop",
+		"index": s.textBlockIndex,
+	})
+	s.textBlockOpen = false
+	s.textBlockIndex = -1
+}
+
+func (s *claudeStreamRuntime) finalize(stopReason string) {
+	if s.ended {
+		return
+	}
+	s.ended = true
+
+	s.closeThinkingBlock()
+	s.closeTextBlock()
+
+	finalThinking := s.thinking.String()
+	finalText := cleanVisibleOutput(s.text.String(), s.stripReferenceMarkers)
+
+	if s.bufferToolContent {
+		detected := toolcall.ParseStandaloneToolCalls(finalText, s.toolNames)
+		if len(detected) == 0 && finalText == "" && finalThinking != "" {
+			detected = toolcall.ParseStandaloneToolCalls(finalThinking, s.toolNames)
+		}
+		if len(detected) > 0 {
+			stopReason = "tool_use"
+			for i, tc := range detected {
+				idx := s.nextBlockIndex + i
+				s.send("content_block_start", map[string]any{
+					"type":  "content_block_start",
+					"index": idx,
+					"content_block": map[string]any{
+						"type":  "tool_use",
+						"id":    fmt.Sprintf("toolu_%d_%d", time.Now().Unix(), idx),
+						"name":  tc.Name,
+						"input": map[string]any{},
+					},
+				})
+
+				inputBytes, _ := json.Marshal(tc.Input)
+				s.send("content_block_delta", map[string]any{
+					"type":  "content_block_delta",
+					"index": idx,
+					"delta": map[string]any{
+						"type":         "input_json_delta",
+						"partial_json": string(inputBytes),
+					},
+				})
+
+				s.send("content_block_stop", map[string]any{
+					"type":  "content_block_stop",
+					"index": idx,
+				})
+			}
+			s.nextBlockIndex += len(detected)
+		} else if finalText != "" {
+			idx := s.nextBlockIndex
+			s.nextBlockIndex++
+			s.send("content_block_start", map[string]any{
+				"type":  "content_block_start",
+				"index": idx,
+				"content_block": map[string]any{
+					"type": "text",
+					"text": "",
+				},
+			})
+			s.send("content_block_delta", map[string]any{
+				"type":  "content_block_delta",
+				"index": idx,
+				"delta": map[string]any{
+					"type": "text_delta",
+					"text": finalText,
+				},
+			})
+			s.send("content_block_stop", map[string]any{
+				"type":  "content_block_stop",
+				"index": idx,
+			})
+		}
+	}
+
+	outputTokens := util.EstimateTokens(finalThinking) + util.EstimateTokens(finalText)
+	s.send("message_delta", map[string]any{
+		"type": "message_delta",
+		"delta": map[string]any{
+			"stop_reason":   stopReason,
+			"stop_sequence": nil,
+		},
+		"usage": map[string]any{
+			"output_tokens": outputTokens,
+		},
+	})
+	s.send("message_stop", map[string]any{"type": "message_stop"})
+}
+
+func (s *claudeStreamRuntime) onFinalize(reason streamengine.StopReason, scannerErr error) {
+	if string(reason) == "upstream_error" {
+		s.sendError(s.upstreamErr)
+		return
+	}
+	if scannerErr != nil {
+		s.sendError(scannerErr.Error())
+		return
+	}
+	s.finalize("end_turn")
+}

internal/httpapi/claude/stream_status_test.go

@@ -0,0 +1,63 @@
+package claude
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"github.com/go-chi/chi/v5"
+	chimw "github.com/go-chi/chi/v5/middleware"
+)
+
+type streamStatusClaudeOpenAIStub struct{}
+
+func (streamStatusClaudeOpenAIStub) ChatCompletions(w http.ResponseWriter, _ *http.Request) {
+	w.Header().Set("Content-Type", "text/event-stream")
+	w.WriteHeader(http.StatusOK)
+	_, _ = w.Write([]byte("data: {\"id\":\"chatcmpl-1\",\"object\":\"chat.completion.chunk\",\"choices\":[{\"index\":0,\"delta\":{\"content\":\"hello\"},\"finish_reason\":null}]}\n\n"))
+	_, _ = w.Write([]byte("data: [DONE]\n\n"))
+}
+
+type streamStatusClaudeStoreStub struct{}
+
+func (streamStatusClaudeStoreStub) ModelAliases() map[string]string { return nil }
+
+func (streamStatusClaudeStoreStub) CompatStripReferenceMarkers() bool { return true }
+
+func captureClaudeStatusMiddleware(statuses *[]int) func(http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			ww := chimw.NewWrapResponseWriter(w, r.ProtoMajor)
+			next.ServeHTTP(ww, r)
+			*statuses = append(*statuses, ww.Status())
+		})
+	}
+}
+
+func TestClaudeMessagesStreamStatusCapturedAs200(t *testing.T) {
+	statuses := make([]int, 0, 1)
+	h := &Handler{
+		Store:  streamStatusClaudeStoreStub{},
+		OpenAI: streamStatusClaudeOpenAIStub{},
+	}
+	r := chi.NewRouter()
+	r.Use(captureClaudeStatusMiddleware(&statuses))
+	RegisterRoutes(r, h)
+
+	reqBody := `{"model":"claude-sonnet-4-5","messages":[{"role":"user","content":"hi"}],"stream":true}`
+	req := httptest.NewRequest(http.MethodPost, "/anthropic/v1/messages", strings.NewReader(reqBody))
+	req.Header.Set("Content-Type", "application/json")
+	rec := httptest.NewRecorder()
+	r.ServeHTTP(rec, req)
+
+	if rec.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d body=%s", rec.Code, rec.Body.String())
+	}
+	if len(statuses) != 1 {
+		t.Fatalf("expected one captured status, got %d", len(statuses))
+	}
+	if statuses[0] != http.StatusOK {
+		t.Fatalf("expected captured status 200 (not 000), got %d", statuses[0])
+	}
+}

internal/httpapi/claude/tool_call_state.go

@@ -0,0 +1,25 @@
+package claude
+
+import (
+	"fmt"
+	"strings"
+)
+
+type claudeToolCallState struct {
+	nameByID       map[string]string
+	lastIDByName   map[string]string
+	callIDSequence int
+}
+
+func (s *claudeToolCallState) nextID() string {
+	s.callIDSequence++
+	return fmt.Sprintf("call_claude_%d", s.callIDSequence)
+}
+
+func safeStringValue(v any) string {
+	s, ok := v.(string)
+	if !ok {
+		return ""
+	}
+	return strings.TrimSpace(s)
+}