feat: add compatibility setting to strip reference markers from model output and update stream handlers accordingly

internal/adapter/claude/deps.go

@@ -22,6 +22,7 @@ type DeepSeekCaller interface {
 
 type ConfigReader interface {
 	ClaudeMapping() map[string]string
+	CompatStripReferenceMarkers() bool
 }
 
 type OpenAIChatRunner interface {

internal/adapter/claude/deps_injection_test.go

@@ -7,6 +7,7 @@ type mockClaudeConfig struct {
 }
 
 func (m mockClaudeConfig) ClaudeMapping() map[string]string { return m.m }
+func (mockClaudeConfig) CompatStripReferenceMarkers() bool  { return true }
 
 func TestNormalizeClaudeRequestUsesConfigInterfaceMapping(t *testing.T) {
 	req := map[string]any{

internal/adapter/claude/handler_messages.go

@@ -149,6 +149,7 @@ func (h *Handler) handleClaudeStreamRealtime(w http.ResponseWriter, r *http.Requ
 		messages,
 		thinkingEnabled,
 		searchEnabled,
+		h.compatStripReferenceMarkers(),
 		toolNames,
 	)
 	streamRuntime.sendMessageStart()

internal/adapter/claude/handler_routes.go

@@ -21,6 +21,13 @@ type Handler struct {
 	OpenAI OpenAIChatRunner
 }
 
+func (h *Handler) compatStripReferenceMarkers() bool {
+	if h == nil || h.Store == nil {
+		return true
+	}
+	return h.Store.CompatStripReferenceMarkers()
+}
+
 var (
 	claudeStreamPingInterval    = time.Duration(deepseek.KeepAliveTimeout) * time.Second
 	claudeStreamIdleTimeout     = time.Duration(deepseek.StreamIdleTimeout) * time.Second

internal/adapter/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/adapter/claude/proxy_vercel_test.go

@@ -16,6 +16,8 @@ func (s claudeProxyStoreStub) ClaudeMapping() map[string]string {
 	return s.mapping
 }
 
+func (claudeProxyStoreStub) CompatStripReferenceMarkers() bool { return true }
+
 type openAIProxyStub struct {
 	status int
 	body   string

internal/adapter/claude/stream_runtime_core.go

@@ -19,13 +19,14 @@ type claudeStreamRuntime struct {
 	toolNames []string
 	messages  []any
 
-	thinkingEnabled   bool
-	searchEnabled     bool
-	bufferToolContent bool
+	thinkingEnabled       bool
+	searchEnabled         bool
+	bufferToolContent     bool
+	stripReferenceMarkers bool
 
-	messageID string
-	thinking  strings.Builder
-	text      strings.Builder
+	messageID    string
+	thinking     strings.Builder
+	text         strings.Builder
 	outputTokens int
 
 	nextBlockIndex     int
@@ -45,21 +46,23 @@ func newClaudeStreamRuntime(
 	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,
-		toolNames:          toolNames,
-		messageID:          fmt.Sprintf("msg_%d", time.Now().UnixNano()),
-		thinkingBlockIndex: -1,
-		textBlockIndex:     -1,
+		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,
 	}
 }
 
@@ -80,10 +83,11 @@ func (s *claudeStreamRuntime) onParsed(parsed sse.LineResult) streamengine.Parse
 
 	contentSeen := false
 	for _, p := range parsed.Parts {
-		if p.Text == "" {
+		cleanedText := cleanVisibleOutput(p.Text, s.stripReferenceMarkers)
+		if cleanedText == "" {
 			continue
 		}
-		if p.Type != "thinking" && s.searchEnabled && sse.IsCitation(p.Text) {
+		if p.Type != "thinking" && s.searchEnabled && sse.IsCitation(cleanedText) {
 			continue
 		}
 		contentSeen = true
@@ -92,7 +96,7 @@ func (s *claudeStreamRuntime) onParsed(parsed sse.LineResult) streamengine.Parse
 			if !s.thinkingEnabled {
 				continue
 			}
-			s.thinking.WriteString(p.Text)
+			s.thinking.WriteString(cleanedText)
 			s.closeTextBlock()
 			if !s.thinkingBlockOpen {
 				s.thinkingBlockIndex = s.nextBlockIndex
@@ -112,13 +116,13 @@ func (s *claudeStreamRuntime) onParsed(parsed sse.LineResult) streamengine.Parse
 				"index": s.thinkingBlockIndex,
 				"delta": map[string]any{
 					"type":     "thinking_delta",
-					"thinking": p.Text,
+					"thinking": cleanedText,
 				},
 			})
 			continue
 		}
 
-		s.text.WriteString(p.Text)
+		s.text.WriteString(cleanedText)
 		if s.bufferToolContent {
 			if hasUnclosedCodeFence(s.text.String()) {
 				continue
@@ -144,7 +148,7 @@ func (s *claudeStreamRuntime) onParsed(parsed sse.LineResult) streamengine.Parse
 			"index": s.textBlockIndex,
 			"delta": map[string]any{
 				"type": "text_delta",
-				"text": p.Text,
+				"text": cleanedText,
 			},
 		})
 	}

internal/adapter/claude/stream_runtime_finalize.go

@@ -43,7 +43,7 @@ func (s *claudeStreamRuntime) finalize(stopReason string) {
 	s.closeTextBlock()
 
 	finalThinking := s.thinking.String()
-	finalText := s.text.String()
+	finalText := cleanVisibleOutput(s.text.String(), s.stripReferenceMarkers)
 
 	if s.bufferToolContent {
 		detected := util.ParseStandaloneToolCalls(finalText, s.toolNames)
@@ -64,7 +64,7 @@ func (s *claudeStreamRuntime) finalize(stopReason string) {
 						"input": map[string]any{},
 					},
 				})
-				
+
 				inputBytes, _ := json.Marshal(tc.Input)
 				s.send("content_block_delta", map[string]any{
 					"type":  "content_block_delta",

internal/adapter/claude/stream_status_test.go

@@ -28,6 +28,8 @@ func (streamStatusClaudeStoreStub) ClaudeMapping() map[string]string {
 	}
 }
 
+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) {

internal/adapter/gemini/deps.go

@@ -22,6 +22,7 @@ type DeepSeekCaller interface {
 
 type ConfigReader interface {
 	ModelAliases() map[string]string
+	CompatStripReferenceMarkers() bool
 }
 
 type OpenAIChatRunner interface {

internal/adapter/gemini/handler_generate.go

@@ -140,7 +140,15 @@ func (h *Handler) handleNonStreamGenerateContent(w http.ResponseWriter, resp *ht
 	}
 
 	result := sse.CollectStream(resp, thinkingEnabled, true)
-	writeJSON(w, http.StatusOK, buildGeminiGenerateContentResponse(model, finalPrompt, result.Thinking, result.Text, toolNames, result.OutputTokens))
+	stripReferenceMarkers := h.compatStripReferenceMarkers()
+	writeJSON(w, http.StatusOK, buildGeminiGenerateContentResponse(
+		model,
+		finalPrompt,
+		cleanVisibleOutput(result.Thinking, stripReferenceMarkers),
+		cleanVisibleOutput(result.Text, stripReferenceMarkers),
+		toolNames,
+		result.OutputTokens,
+	))
 }
 
 func buildGeminiGenerateContentResponse(model, finalPrompt, finalThinking, finalText string, toolNames []string, outputTokens int) map[string]any {
@@ -179,7 +187,7 @@ func buildGeminiUsage(finalPrompt, finalThinking, finalText string, outputTokens
 
 func buildGeminiPartsFromFinal(finalText, finalThinking string, toolNames []string) []map[string]any {
 	detected := util.ParseToolCalls(finalText, toolNames)
-	if len(detected) == 0 && strings.TrimSpace(finalThinking) != "" {
+	if len(detected) == 0 && finalThinking != "" {
 		detected = util.ParseToolCalls(finalThinking, toolNames)
 	}
 	if len(detected) > 0 {
@@ -196,7 +204,7 @@ func buildGeminiPartsFromFinal(finalText, finalThinking string, toolNames []stri
 	}
 
 	text := finalText
-	if strings.TrimSpace(text) == "" {
+	if text == "" {
 		text = finalThinking
 	}
 	return []map[string]any{{"text": text}}

internal/adapter/gemini/handler_routes.go

@@ -17,6 +17,13 @@ type Handler struct {
 	OpenAI OpenAIChatRunner
 }
 
+func (h *Handler) compatStripReferenceMarkers() bool {
+	if h == nil || h.Store == nil {
+		return true
+	}
+	return h.Store.CompatStripReferenceMarkers()
+}
+
 func RegisterRoutes(r chi.Router, h *Handler) {
 	r.Post("/v1beta/models/{model}:generateContent", h.GenerateContent)
 	r.Post("/v1beta/models/{model}:streamGenerateContent", h.StreamGenerateContent)

internal/adapter/gemini/handler_stream_runtime.go

@@ -27,7 +27,7 @@ func (h *Handler) handleStreamGenerateContent(w http.ResponseWriter, r *http.Req
 
 	rc := http.NewResponseController(w)
 	_, canFlush := w.(http.Flusher)
-	runtime := newGeminiStreamRuntime(w, rc, canFlush, model, finalPrompt, thinkingEnabled, searchEnabled, toolNames)
+	runtime := newGeminiStreamRuntime(w, rc, canFlush, model, finalPrompt, thinkingEnabled, searchEnabled, h.compatStripReferenceMarkers(), toolNames)
 
 	initialType := "text"
 	if thinkingEnabled {
@@ -57,13 +57,14 @@ type geminiStreamRuntime struct {
 	model       string
 	finalPrompt string
 
-	thinkingEnabled bool
-	searchEnabled   bool
-	bufferContent   bool
-	toolNames       []string
+	thinkingEnabled       bool
+	searchEnabled         bool
+	bufferContent         bool
+	stripReferenceMarkers bool
+	toolNames             []string
 
-	thinking strings.Builder
-	text     strings.Builder
+	thinking     strings.Builder
+	text         strings.Builder
 	outputTokens int
 }
 
@@ -75,18 +76,20 @@ func newGeminiStreamRuntime(
 	finalPrompt string,
 	thinkingEnabled bool,
 	searchEnabled bool,
+	stripReferenceMarkers bool,
 	toolNames []string,
 ) *geminiStreamRuntime {
 	return &geminiStreamRuntime{
-		w:               w,
-		rc:              rc,
-		canFlush:        canFlush,
-		model:           model,
-		finalPrompt:     finalPrompt,
-		thinkingEnabled: thinkingEnabled,
-		searchEnabled:   searchEnabled,
-		bufferContent:   len(toolNames) > 0,
-		toolNames:       toolNames,
+		w:                     w,
+		rc:                    rc,
+		canFlush:              canFlush,
+		model:                 model,
+		finalPrompt:           finalPrompt,
+		thinkingEnabled:       thinkingEnabled,
+		searchEnabled:         searchEnabled,
+		bufferContent:         len(toolNames) > 0,
+		stripReferenceMarkers: stripReferenceMarkers,
+		toolNames:             toolNames,
 	}
 }
 
@@ -113,20 +116,21 @@ func (s *geminiStreamRuntime) onParsed(parsed sse.LineResult) streamengine.Parse
 
 	contentSeen := false
 	for _, p := range parsed.Parts {
-		if p.Text == "" {
+		cleanedText := cleanVisibleOutput(p.Text, s.stripReferenceMarkers)
+		if cleanedText == "" {
 			continue
 		}
-		if p.Type != "thinking" && s.searchEnabled && sse.IsCitation(p.Text) {
+		if p.Type != "thinking" && s.searchEnabled && sse.IsCitation(cleanedText) {
 			continue
 		}
 		contentSeen = true
 		if p.Type == "thinking" {
 			if s.thinkingEnabled {
-				s.thinking.WriteString(p.Text)
+				s.thinking.WriteString(cleanedText)
 			}
 			continue
 		}
-		s.text.WriteString(p.Text)
+		s.text.WriteString(cleanedText)
 		if s.bufferContent {
 			continue
 		}
@@ -136,7 +140,7 @@ func (s *geminiStreamRuntime) onParsed(parsed sse.LineResult) streamengine.Parse
 					"index": 0,
 					"content": map[string]any{
 						"role":  "model",
-						"parts": []map[string]any{{"text": p.Text}},
+						"parts": []map[string]any{{"text": cleanedText}},
 					},
 				},
 			},
@@ -148,7 +152,7 @@ func (s *geminiStreamRuntime) onParsed(parsed sse.LineResult) streamengine.Parse
 
 func (s *geminiStreamRuntime) finalize() {
 	finalThinking := s.thinking.String()
-	finalText := s.text.String()
+	finalText := cleanVisibleOutput(s.text.String(), s.stripReferenceMarkers)
 
 	if s.bufferContent {
 		parts := buildGeminiPartsFromFinal(finalText, finalThinking, s.toolNames)

internal/adapter/gemini/handler_test.go

@@ -17,7 +17,8 @@ import (
 
 type testGeminiConfig struct{}
 
-func (testGeminiConfig) ModelAliases() map[string]string { return nil }
+func (testGeminiConfig) ModelAliases() map[string]string   { return nil }
+func (testGeminiConfig) CompatStripReferenceMarkers() bool { return true }
 
 type testGeminiAuth struct {
 	a   *auth.RequestAuth
@@ -62,8 +63,8 @@ func (m testGeminiDS) CallCompletion(_ context.Context, _ *auth.RequestAuth, _ m
 }
 
 type geminiOpenAIErrorStub struct {
-	status int
-	body   string
+	status  int
+	body    string
 	headers map[string]string
 }
 
@@ -247,7 +248,7 @@ func TestStreamGenerateContentEmitsSSE(t *testing.T) {
 
 func TestGenerateContentOpenAIProxyErrorUsesGeminiEnvelope(t *testing.T) {
 	h := &Handler{
-		Store:  testGeminiConfig{},
+		Store: testGeminiConfig{},
 		OpenAI: geminiOpenAIErrorStub{
 			status: http.StatusUnauthorized,
 			body:   `{"error":{"message":"invalid api key"}}`,

internal/adapter/gemini/output_clean.go

@@ -0,0 +1,13 @@
+package gemini
+
+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/adapter/openai/chat_stream_runtime.go

@@ -22,8 +22,9 @@ type chatStreamRuntime struct {
 	finalPrompt  string
 	toolNames    []string
 
-	thinkingEnabled bool
-	searchEnabled   bool
+	thinkingEnabled       bool
+	searchEnabled         bool
+	stripReferenceMarkers bool
 
 	firstChunkSent       bool
 	bufferToolContent    bool
@@ -49,25 +50,27 @@ func newChatStreamRuntime(
 	finalPrompt string,
 	thinkingEnabled bool,
 	searchEnabled bool,
+	stripReferenceMarkers bool,
 	toolNames []string,
 	bufferToolContent bool,
 	emitEarlyToolDeltas bool,
 ) *chatStreamRuntime {
 	return &chatStreamRuntime{
-		w:                   w,
-		rc:                  rc,
-		canFlush:            canFlush,
-		completionID:        completionID,
-		created:             created,
-		model:               model,
-		finalPrompt:         finalPrompt,
-		toolNames:           toolNames,
-		thinkingEnabled:     thinkingEnabled,
-		searchEnabled:       searchEnabled,
-		bufferToolContent:   bufferToolContent,
-		emitEarlyToolDeltas: emitEarlyToolDeltas,
-		streamToolCallIDs:   map[int]string{},
-		streamToolNames:     map[int]string{},
+		w:                     w,
+		rc:                    rc,
+		canFlush:              canFlush,
+		completionID:          completionID,
+		created:               created,
+		model:                 model,
+		finalPrompt:           finalPrompt,
+		toolNames:             toolNames,
+		thinkingEnabled:       thinkingEnabled,
+		searchEnabled:         searchEnabled,
+		stripReferenceMarkers: stripReferenceMarkers,
+		bufferToolContent:     bufferToolContent,
+		emitEarlyToolDeltas:   emitEarlyToolDeltas,
+		streamToolCallIDs:     map[int]string{},
+		streamToolNames:       map[int]string{},
 	}
 }
 
@@ -98,7 +101,7 @@ func (s *chatStreamRuntime) sendDone() {
 
 func (s *chatStreamRuntime) finalize(finishReason string) {
 	finalThinking := s.thinking.String()
-	finalText := sanitizeLeakedOutput(s.text.String())
+	finalText := cleanVisibleOutput(s.text.String(), s.stripReferenceMarkers)
 	detected := util.ParseStandaloneToolCallsDetailed(finalText, s.toolNames)
 	if len(detected.Calls) > 0 && !s.toolCallsDoneEmitted {
 		finishReason = "tool_calls"
@@ -142,7 +145,7 @@ func (s *chatStreamRuntime) finalize(finishReason string) {
 			if evt.Content == "" {
 				continue
 			}
-			cleaned := sanitizeLeakedOutput(evt.Content)
+			cleaned := cleanVisibleOutput(evt.Content, s.stripReferenceMarkers)
 			if cleaned == "" {
 				continue
 			}
@@ -203,10 +206,11 @@ func (s *chatStreamRuntime) onParsed(parsed sse.LineResult) streamengine.ParsedD
 	newChoices := make([]map[string]any, 0, len(parsed.Parts))
 	contentSeen := false
 	for _, p := range parsed.Parts {
-		if s.searchEnabled && sse.IsCitation(p.Text) {
+		cleanedText := cleanVisibleOutput(p.Text, s.stripReferenceMarkers)
+		if s.searchEnabled && sse.IsCitation(cleanedText) {
 			continue
 		}
-		if p.Text == "" {
+		if cleanedText == "" {
 			continue
 		}
 		contentSeen = true
@@ -217,15 +221,15 @@ func (s *chatStreamRuntime) onParsed(parsed sse.LineResult) streamengine.ParsedD
 		}
 		if p.Type == "thinking" {
 			if s.thinkingEnabled {
-				s.thinking.WriteString(p.Text)
-				delta["reasoning_content"] = p.Text
+				s.thinking.WriteString(cleanedText)
+				delta["reasoning_content"] = cleanedText
 			}
 		} else {
-			s.text.WriteString(p.Text)
+			s.text.WriteString(cleanedText)
 			if !s.bufferToolContent {
-				delta["content"] = p.Text
+				delta["content"] = cleanedText
 			} else {
-				events := processToolSieveChunk(&s.toolSieve, p.Text, s.toolNames)
+				events := processToolSieveChunk(&s.toolSieve, cleanedText, s.toolNames)
 				for _, evt := range events {
 					if len(evt.ToolCallDeltas) > 0 {
 						if !s.emitEarlyToolDeltas {
@@ -264,7 +268,7 @@ func (s *chatStreamRuntime) onParsed(parsed sse.LineResult) streamengine.ParsedD
 						continue
 					}
 					if evt.Content != "" {
-						cleaned := sanitizeLeakedOutput(evt.Content)
+						cleaned := cleanVisibleOutput(evt.Content, s.stripReferenceMarkers)
 						if cleaned == "" {
 							continue
 						}

internal/adapter/openai/deps.go

@@ -25,6 +25,7 @@ type DeepSeekCaller interface {
 type ConfigReader interface {
 	ModelAliases() map[string]string
 	CompatWideInputStrictOutput() bool
+	CompatStripReferenceMarkers() bool
 	ToolcallMode() string
 	ToolcallEarlyEmitConfidence() string
 	ResponsesStoreTTLSeconds() int

internal/adapter/openai/deps_injection_test.go

@@ -15,6 +15,7 @@ func (m mockOpenAIConfig) ModelAliases() map[string]string { return m.aliases }
 func (m mockOpenAIConfig) CompatWideInputStrictOutput() bool {
 	return m.wideInput
 }
+func (m mockOpenAIConfig) CompatStripReferenceMarkers() bool   { return true }
 func (m mockOpenAIConfig) ToolcallMode() string                { return m.toolMode }
 func (m mockOpenAIConfig) ToolcallEarlyEmitConfidence() string { return m.earlyEmit }
 func (m mockOpenAIConfig) ResponsesStoreTTLSeconds() int       { return m.responsesTTL }

internal/adapter/openai/handler_chat.go

@@ -104,9 +104,10 @@ func (h *Handler) handleNonStream(w http.ResponseWriter, ctx context.Context, re
 	_ = ctx
 	result := sse.CollectStream(resp, thinkingEnabled, true)
 
-	finalThinking := result.Thinking
-	finalText := sanitizeLeakedOutput(result.Text)
-	if writeUpstreamEmptyOutputError(w, result) {
+	stripReferenceMarkers := h.compatStripReferenceMarkers()
+	finalThinking := cleanVisibleOutput(result.Thinking, stripReferenceMarkers)
+	finalText := cleanVisibleOutput(result.Text, stripReferenceMarkers)
+	if writeUpstreamEmptyOutputError(w, finalThinking, finalText, result.ContentFilter) {
 		return
 	}
 	respBody := openaifmt.BuildChatCompletion(completionID, model, finalPrompt, finalThinking, finalText, toolNames)
@@ -141,6 +142,7 @@ func (h *Handler) handleStream(w http.ResponseWriter, r *http.Request, resp *htt
 	created := time.Now().Unix()
 	bufferToolContent := len(toolNames) > 0
 	emitEarlyToolDeltas := h.toolcallFeatureMatchEnabled() && h.toolcallEarlyEmitHighConfidence()
+	stripReferenceMarkers := h.compatStripReferenceMarkers()
 	initialType := "text"
 	if thinkingEnabled {
 		initialType = "thinking"
@@ -156,6 +158,7 @@ func (h *Handler) handleStream(w http.ResponseWriter, r *http.Request, resp *htt
 		finalPrompt,
 		thinkingEnabled,
 		searchEnabled,
+		stripReferenceMarkers,
 		toolNames,
 		bufferToolContent,
 		emitEarlyToolDeltas,

internal/adapter/openai/handler_routes.go

@@ -28,6 +28,13 @@ type Handler struct {
 	responses    *responseStore
 }
 
+func (h *Handler) compatStripReferenceMarkers() bool {
+	if h == nil || h.Store == nil {
+		return true
+	}
+	return h.Store.CompatStripReferenceMarkers()
+}
+
 type streamLease struct {
 	Auth      *auth.RequestAuth
 	ExpiresAt time.Time

internal/adapter/openai/output_clean.go

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

internal/adapter/openai/responses_handler.go

@@ -113,8 +113,10 @@ func (h *Handler) handleResponsesNonStream(w http.ResponseWriter, resp *http.Res
 		return
 	}
 	result := sse.CollectStream(resp, thinkingEnabled, true)
-	sanitizedText := sanitizeLeakedOutput(result.Text)
-	if writeUpstreamEmptyOutputError(w, result) {
+	stripReferenceMarkers := h.compatStripReferenceMarkers()
+	sanitizedThinking := cleanVisibleOutput(result.Thinking, stripReferenceMarkers)
+	sanitizedText := cleanVisibleOutput(result.Text, stripReferenceMarkers)
+	if writeUpstreamEmptyOutputError(w, sanitizedThinking, sanitizedText, result.ContentFilter) {
 		return
 	}
 	textParsed := util.ParseStandaloneToolCallsDetailed(sanitizedText, toolNames)
@@ -126,7 +128,7 @@ func (h *Handler) handleResponsesNonStream(w http.ResponseWriter, resp *http.Res
 		return
 	}
 
-	responseObj := openaifmt.BuildResponseObject(responseID, model, finalPrompt, result.Thinking, sanitizedText, toolNames)
+	responseObj := openaifmt.BuildResponseObject(responseID, model, finalPrompt, sanitizedThinking, sanitizedText, toolNames)
 	if result.OutputTokens > 0 {
 		if usage, ok := responseObj["usage"].(map[string]any); ok {
 			usage["output_tokens"] = result.OutputTokens
@@ -159,6 +161,7 @@ func (h *Handler) handleResponsesStream(w http.ResponseWriter, r *http.Request,
 	}
 	bufferToolContent := len(toolNames) > 0
 	emitEarlyToolDeltas := h.toolcallFeatureMatchEnabled() && h.toolcallEarlyEmitHighConfidence()
+	stripReferenceMarkers := h.compatStripReferenceMarkers()
 
 	streamRuntime := newResponsesStreamRuntime(
 		w,
@@ -169,6 +172,7 @@ func (h *Handler) handleResponsesStream(w http.ResponseWriter, r *http.Request,
 		finalPrompt,
 		thinkingEnabled,
 		searchEnabled,
+		stripReferenceMarkers,
 		toolNames,
 		bufferToolContent,
 		emitEarlyToolDeltas,

internal/adapter/openai/responses_stream_runtime_core.go

@@ -23,8 +23,9 @@ type responsesStreamRuntime struct {
 	traceID     string
 	toolChoice  util.ToolChoicePolicy
 
-	thinkingEnabled bool
-	searchEnabled   bool
+	thinkingEnabled       bool
+	searchEnabled         bool
+	stripReferenceMarkers bool
 
 	bufferToolContent    bool
 	emitEarlyToolDeltas  bool
@@ -63,6 +64,7 @@ func newResponsesStreamRuntime(
 	finalPrompt string,
 	thinkingEnabled bool,
 	searchEnabled bool,
+	stripReferenceMarkers bool,
 	toolNames []string,
 	bufferToolContent bool,
 	emitEarlyToolDeltas bool,
@@ -71,34 +73,35 @@ func newResponsesStreamRuntime(
 	persistResponse func(obj map[string]any),
 ) *responsesStreamRuntime {
 	return &responsesStreamRuntime{
-		w:                   w,
-		rc:                  rc,
-		canFlush:            canFlush,
-		responseID:          responseID,
-		model:               model,
-		finalPrompt:         finalPrompt,
-		thinkingEnabled:     thinkingEnabled,
-		searchEnabled:       searchEnabled,
-		toolNames:           toolNames,
-		bufferToolContent:   bufferToolContent,
-		emitEarlyToolDeltas: emitEarlyToolDeltas,
-		streamToolCallIDs:   map[int]string{},
-		functionItemIDs:     map[int]string{},
-		functionOutputIDs:   map[int]int{},
-		functionArgs:        map[int]string{},
-		functionDone:        map[int]bool{},
-		functionAdded:       map[int]bool{},
-		functionNames:       map[int]string{},
-		messageOutputID:     -1,
-		toolChoice:          toolChoice,
-		traceID:             traceID,
-		persistResponse:     persistResponse,
+		w:                     w,
+		rc:                    rc,
+		canFlush:              canFlush,
+		responseID:            responseID,
+		model:                 model,
+		finalPrompt:           finalPrompt,
+		thinkingEnabled:       thinkingEnabled,
+		searchEnabled:         searchEnabled,
+		stripReferenceMarkers: stripReferenceMarkers,
+		toolNames:             toolNames,
+		bufferToolContent:     bufferToolContent,
+		emitEarlyToolDeltas:   emitEarlyToolDeltas,
+		streamToolCallIDs:     map[int]string{},
+		functionItemIDs:       map[int]string{},
+		functionOutputIDs:     map[int]int{},
+		functionArgs:          map[int]string{},
+		functionDone:          map[int]bool{},
+		functionAdded:         map[int]bool{},
+		functionNames:         map[int]string{},
+		messageOutputID:       -1,
+		toolChoice:            toolChoice,
+		traceID:               traceID,
+		persistResponse:       persistResponse,
 	}
 }
 
 func (s *responsesStreamRuntime) finalize() {
 	finalThinking := s.thinking.String()
-	finalText := sanitizeLeakedOutput(s.text.String())
+	finalText := cleanVisibleOutput(s.text.String(), s.stripReferenceMarkers)
 
 	if s.bufferToolContent {
 		s.processToolStreamEvents(flushToolSieve(&s.sieve, s.toolNames), true)
@@ -190,10 +193,11 @@ func (s *responsesStreamRuntime) onParsed(parsed sse.LineResult) streamengine.Pa
 
 	contentSeen := false
 	for _, p := range parsed.Parts {
-		if p.Text == "" {
+		cleanedText := cleanVisibleOutput(p.Text, s.stripReferenceMarkers)
+		if cleanedText == "" {
 			continue
 		}
-		if p.Type != "thinking" && s.searchEnabled && sse.IsCitation(p.Text) {
+		if p.Type != "thinking" && s.searchEnabled && sse.IsCitation(cleanedText) {
 			continue
 		}
 		contentSeen = true
@@ -201,15 +205,11 @@ func (s *responsesStreamRuntime) onParsed(parsed sse.LineResult) streamengine.Pa
 			if !s.thinkingEnabled {
 				continue
 			}
-			s.thinking.WriteString(p.Text)
-			s.sendEvent("response.reasoning.delta", openaifmt.BuildResponsesReasoningDeltaPayload(s.responseID, p.Text))
+			s.thinking.WriteString(cleanedText)
+			s.sendEvent("response.reasoning.delta", openaifmt.BuildResponsesReasoningDeltaPayload(s.responseID, cleanedText))
 			continue
 		}
 
-		cleanedText := sanitizeLeakedOutput(p.Text)
-		if cleanedText == "" {
-			continue
-		}
 		s.text.WriteString(cleanedText)
 		if !s.bufferToolContent {
 			s.emitTextDelta(cleanedText)

internal/adapter/openai/responses_stream_runtime_toolcalls.go

@@ -69,7 +69,7 @@ func (s *responsesStreamRuntime) ensureMessageContentPartAdded() {
 }
 
 func (s *responsesStreamRuntime) emitTextDelta(content string) {
-	if strings.TrimSpace(content) == "" {
+	if content == "" {
 		return
 	}
 	s.ensureMessageContentPartAdded()

internal/adapter/openai/responses_stream_runtime_toolcalls_finalize.go

@@ -83,13 +83,13 @@ func (s *responsesStreamRuntime) buildCompletedResponseObject(finalThinking, fin
 		})
 	} else if len(calls) == 0 {
 		content := make([]map[string]any, 0, 2)
-		if strings.TrimSpace(finalThinking) != "" {
+		if finalThinking != "" {
 			content = append(content, map[string]any{
 				"type": "reasoning",
 				"text": finalThinking,
 			})
 		}
-		if strings.TrimSpace(finalText) != "" {
+		if finalText != "" {
 			content = append(content, map[string]any{
 				"type": "output_text",
 				"text": finalText,
@@ -136,10 +136,10 @@ func (s *responsesStreamRuntime) buildCompletedResponseObject(finalThinking, fin
 	}
 
 	outputText := s.visibleText.String()
-	if strings.TrimSpace(outputText) == "" && len(calls) == 0 {
-		if strings.TrimSpace(finalText) != "" {
+	if outputText == "" && len(calls) == 0 {
+		if finalText != "" {
 			outputText = finalText
-		} else if strings.TrimSpace(finalThinking) != "" {
+		} else if finalThinking != "" {
 			outputText = finalThinking
 		}
 	}

internal/adapter/openai/tool_sieve_state.go

@@ -48,7 +48,7 @@ func (s *toolStreamSieveState) resetIncrementalToolState() {
 }
 
 func (s *toolStreamSieveState) noteText(content string) {
-	if strings.TrimSpace(content) == "" {
+	if content == "" {
 		return
 	}
 	s.recentTextTail = appendTail(s.recentTextTail, content, toolSieveContextTailLimit)

internal/adapter/openai/upstream_empty.go

@@ -1,17 +1,12 @@
 package openai
 
-import (
-	"net/http"
-	"strings"
+import "net/http"
 
-	"ds2api/internal/sse"
-)
-
-func writeUpstreamEmptyOutputError(w http.ResponseWriter, result sse.CollectResult) bool {
-	if strings.TrimSpace(result.Thinking) != "" || strings.TrimSpace(sanitizeLeakedOutput(result.Text)) != "" {
+func writeUpstreamEmptyOutputError(w http.ResponseWriter, thinking, text string, contentFilter bool) bool {
+	if thinking != "" || text != "" {
 		return false
 	}
-	if result.ContentFilter {
+	if contentFilter {
 		writeOpenAIErrorWithCode(w, http.StatusBadRequest, "Upstream content filtered the response and returned no output.", "content_filter")
 		return true
 	}

internal/adapter/openai/vercel_stream.go

@@ -99,10 +99,13 @@ func (h *Handler) handleVercelStreamPrepare(w http.ResponseWriter, r *http.Reque
 		"final_prompt":     stdReq.FinalPrompt,
 		"thinking_enabled": stdReq.Thinking,
 		"search_enabled":   stdReq.Search,
-		"tool_names":       stdReq.ToolNames,
-		"deepseek_token":   a.DeepSeekToken,
-		"pow_header":       powHeader,
-		"payload":          payload,
+		"compat": map[string]any{
+			"strip_reference_markers": h.compatStripReferenceMarkers(),
+		},
+		"tool_names":     stdReq.ToolNames,
+		"deepseek_token": a.DeepSeekToken,
+		"pow_header":     powHeader,
+		"payload":        payload,
 	})
 }