feat: implement history split functionality to optimize context usage and add corresponding UI settings

internal/adapter/openai/deps.go

@@ -34,6 +34,8 @@ type ConfigReader interface {
 	EmbeddingsProvider() string
 	AutoDeleteMode() string
 	AutoDeleteSessions() bool
+	HistorySplitEnabled() bool
+	HistorySplitTriggerAfterTurns() int
 }
 
 var _ AuthResolver = (*auth.Resolver)(nil)

internal/adapter/openai/deps_injection_test.go

@@ -3,13 +3,15 @@ package openai
 import "testing"
 
 type mockOpenAIConfig struct {
-	aliases        map[string]string
-	wideInput      bool
-	autoDeleteMode string
-	toolMode       string
-	earlyEmit      string
-	responsesTTL   int
-	embedProv      string
+	aliases             map[string]string
+	wideInput           bool
+	autoDeleteMode      string
+	toolMode            string
+	earlyEmit           string
+	responsesTTL        int
+	embedProv           string
+	historySplitEnabled bool
+	historySplitTurns   int
 }
 
 func (m mockOpenAIConfig) ModelAliases() map[string]string { return m.aliases }
@@ -27,7 +29,14 @@ func (m mockOpenAIConfig) AutoDeleteMode() string {
 	}
 	return m.autoDeleteMode
 }
-func (m mockOpenAIConfig) AutoDeleteSessions() bool { return false }
+func (m mockOpenAIConfig) AutoDeleteSessions() bool  { return false }
+func (m mockOpenAIConfig) HistorySplitEnabled() bool { return m.historySplitEnabled }
+func (m mockOpenAIConfig) HistorySplitTriggerAfterTurns() int {
+	if m.historySplitTurns <= 0 {
+		return 1
+	}
+	return m.historySplitTurns
+}
 
 func TestNormalizeOpenAIChatRequestWithConfigInterface(t *testing.T) {
 	cfg := mockOpenAIConfig{

internal/adapter/openai/handler_chat.go

@@ -63,6 +63,11 @@ func (h *Handler) ChatCompletions(w http.ResponseWriter, r *http.Request) {
 		writeOpenAIError(w, http.StatusBadRequest, err.Error())
 		return
 	}
+	stdReq, err = h.applyHistorySplit(r.Context(), a, stdReq)
+	if err != nil {
+		writeOpenAIError(w, http.StatusInternalServerError, err.Error())
+		return
+	}
 	historySession := startChatHistory(h.ChatHistory, r, a, stdReq)
 
 	sessionID, err = h.DS.CreateSession(r.Context(), a, 3)
@@ -155,7 +160,7 @@ func (h *Handler) handleNonStream(w http.ResponseWriter, resp *http.Response, co
 	if searchEnabled {
 		finalText = replaceCitationMarkersWithLinks(finalText, result.CitationLinks)
 	}
-	if shouldWriteUpstreamEmptyOutputError(finalText, result.ContentFilter) {
+	if shouldWriteUpstreamEmptyOutputError(finalText) {
 		status, message, code := upstreamEmptyOutputDetail(result.ContentFilter, finalText, finalThinking)
 		if historySession != nil {
 			historySession.error(status, message, code, finalThinking, finalText)

internal/adapter/openai/history_split.go

@@ -0,0 +1,213 @@
+package openai
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"strings"
+
+	"ds2api/internal/auth"
+	"ds2api/internal/deepseek"
+	"ds2api/internal/util"
+)
+
+const (
+	historySplitFilename    = "HISTORY.txt"
+	historySplitContentType = "text/plain; charset=utf-8"
+	historySplitPurpose     = "assistants"
+)
+
+func (h *Handler) applyHistorySplit(ctx context.Context, a *auth.RequestAuth, stdReq util.StandardRequest) (util.StandardRequest, error) {
+	if h == nil || h.DS == nil || h.Store == nil || a == nil {
+		return stdReq, nil
+	}
+	if !h.Store.HistorySplitEnabled() {
+		return stdReq, nil
+	}
+
+	promptMessages, historyMessages := splitOpenAIHistoryMessages(stdReq.Messages, h.Store.HistorySplitTriggerAfterTurns())
+	if len(historyMessages) == 0 {
+		return stdReq, nil
+	}
+
+	historyText := buildOpenAIHistoryTranscript(historyMessages)
+	if strings.TrimSpace(historyText) == "" {
+		return stdReq, errors.New("history split produced empty transcript")
+	}
+
+	result, err := h.DS.UploadFile(ctx, a, deepseek.UploadFileRequest{
+		Filename:    historySplitFilename,
+		ContentType: historySplitContentType,
+		Purpose:     historySplitPurpose,
+		Data:        []byte(historyText),
+	}, 3)
+	if err != nil {
+		return stdReq, fmt.Errorf("upload history file: %w", err)
+	}
+	fileID := strings.TrimSpace(result.ID)
+	if fileID == "" {
+		return stdReq, errors.New("upload history file returned empty file id")
+	}
+
+	stdReq.Messages = promptMessages
+	stdReq.RefFileIDs = prependUniqueRefFileID(stdReq.RefFileIDs, fileID)
+	stdReq.FinalPrompt, stdReq.ToolNames = buildHistorySplitPrompt(promptMessages, stdReq.ToolsRaw, stdReq.ToolChoice, stdReq.Thinking)
+	return stdReq, nil
+}
+
+func buildHistorySplitPrompt(messages []any, toolsRaw any, toolPolicy util.ToolChoicePolicy, thinkingEnabled bool) (string, []string) {
+	if len(messages) == 0 {
+		return "", nil
+	}
+	instruction := historySplitPromptInstruction()
+	withInstruction := make([]any, 0, len(messages)+1)
+	withInstruction = append(withInstruction, map[string]any{
+		"role":    "system",
+		"content": instruction,
+	})
+	withInstruction = append(withInstruction, messages...)
+	return buildOpenAIFinalPromptWithPolicy(withInstruction, toolsRaw, "", toolPolicy, thinkingEnabled)
+}
+
+func historySplitPromptInstruction() string {
+	return "An attached HISTORY.txt file contains prior conversation history and tool progress. Read it first, then answer the latest user request using that history as context."
+}
+
+func splitOpenAIHistoryMessages(messages []any, triggerAfterTurns int) ([]any, []any) {
+	if triggerAfterTurns <= 0 {
+		triggerAfterTurns = 1
+	}
+	lastUserIndex := -1
+	userTurns := 0
+	for i, raw := range messages {
+		msg, ok := raw.(map[string]any)
+		if !ok {
+			continue
+		}
+		role := strings.ToLower(strings.TrimSpace(asString(msg["role"])))
+		if role != "user" {
+			continue
+		}
+		userTurns++
+		lastUserIndex = i
+	}
+	if userTurns <= triggerAfterTurns || lastUserIndex < 0 {
+		return messages, nil
+	}
+
+	promptMessages := make([]any, 0, len(messages)-lastUserIndex)
+	historyMessages := make([]any, 0, lastUserIndex)
+	for i, raw := range messages {
+		msg, ok := raw.(map[string]any)
+		if !ok {
+			if i >= lastUserIndex {
+				promptMessages = append(promptMessages, raw)
+			} else {
+				historyMessages = append(historyMessages, raw)
+			}
+			continue
+		}
+		role := strings.ToLower(strings.TrimSpace(asString(msg["role"])))
+		switch role {
+		case "system", "developer":
+			promptMessages = append(promptMessages, raw)
+		default:
+			if i >= lastUserIndex {
+				promptMessages = append(promptMessages, raw)
+			} else {
+				historyMessages = append(historyMessages, raw)
+			}
+		}
+	}
+	if len(promptMessages) == 0 {
+		return messages, nil
+	}
+	return promptMessages, historyMessages
+}
+
+func buildOpenAIHistoryTranscript(messages []any) string {
+	var b strings.Builder
+	b.WriteString("# HISTORY.txt\n")
+	b.WriteString("Prior conversation history and tool progress.\n\n")
+
+	entry := 0
+	for _, raw := range messages {
+		msg, ok := raw.(map[string]any)
+		if !ok {
+			continue
+		}
+		role := strings.ToLower(strings.TrimSpace(asString(msg["role"])))
+		content := buildOpenAIHistoryEntry(role, msg)
+		if strings.TrimSpace(content) == "" {
+			continue
+		}
+		entry++
+		fmt.Fprintf(&b, "=== %d. %s ===\n%s\n\n", entry, strings.ToUpper(roleLabelForHistory(role)), content)
+	}
+	return strings.TrimSpace(b.String()) + "\n"
+}
+
+func buildOpenAIHistoryEntry(role string, msg map[string]any) string {
+	switch role {
+	case "assistant":
+		return strings.TrimSpace(buildAssistantContentForPrompt(msg))
+	case "tool", "function":
+		return strings.TrimSpace(buildToolHistoryContent(msg))
+	case "user":
+		return strings.TrimSpace(normalizeOpenAIContentForPrompt(msg["content"]))
+	default:
+		return strings.TrimSpace(normalizeOpenAIContentForPrompt(msg["content"]))
+	}
+}
+
+func buildToolHistoryContent(msg map[string]any) string {
+	content := strings.TrimSpace(normalizeOpenAIContentForPrompt(msg["content"]))
+	parts := make([]string, 0, 2)
+	if name := strings.TrimSpace(asString(msg["name"])); name != "" {
+		parts = append(parts, "name="+name)
+	}
+	if callID := strings.TrimSpace(asString(msg["tool_call_id"])); callID != "" {
+		parts = append(parts, "tool_call_id="+callID)
+	}
+	header := ""
+	if len(parts) > 0 {
+		header = "[" + strings.Join(parts, " ") + "]"
+	}
+	switch {
+	case header != "" && content != "":
+		return header + "\n" + content
+	case header != "":
+		return header
+	default:
+		return content
+	}
+}
+
+func roleLabelForHistory(role string) string {
+	role = strings.ToLower(strings.TrimSpace(role))
+	switch role {
+	case "function":
+		return "tool"
+	case "":
+		return "unknown"
+	default:
+		return role
+	}
+}
+
+func prependUniqueRefFileID(existing []string, fileID string) []string {
+	fileID = strings.TrimSpace(fileID)
+	if fileID == "" {
+		return existing
+	}
+	out := make([]string, 0, len(existing)+1)
+	out = append(out, fileID)
+	for _, id := range existing {
+		trimmed := strings.TrimSpace(id)
+		if trimmed == "" || strings.EqualFold(trimmed, fileID) {
+			continue
+		}
+		out = append(out, trimmed)
+	}
+	return out
+}

internal/adapter/openai/history_split_test.go

@@ -0,0 +1,317 @@
+package openai
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"github.com/go-chi/chi/v5"
+
+	"ds2api/internal/auth"
+	"ds2api/internal/util"
+)
+
+func historySplitTestMessages() []any {
+	toolCalls := []any{
+		map[string]any{
+			"name":      "search",
+			"arguments": map[string]any{"query": "docs"},
+		},
+	}
+	return []any{
+		map[string]any{"role": "system", "content": "system instructions"},
+		map[string]any{"role": "user", "content": "first user turn"},
+		map[string]any{
+			"role":              "assistant",
+			"content":           "",
+			"reasoning_content": "hidden reasoning",
+			"tool_calls":        toolCalls,
+		},
+		map[string]any{
+			"role":         "tool",
+			"name":         "search",
+			"tool_call_id": "call-1",
+			"content":      "tool result",
+		},
+		map[string]any{"role": "user", "content": "latest user turn"},
+	}
+}
+
+func TestBuildOpenAIHistoryTranscriptPreservesOrderAndToolHistory(t *testing.T) {
+	promptMessages, historyMessages := splitOpenAIHistoryMessages(historySplitTestMessages(), 1)
+	if len(promptMessages) != 2 {
+		t.Fatalf("expected 2 prompt messages, got %d", len(promptMessages))
+	}
+	if len(historyMessages) != 3 {
+		t.Fatalf("expected 3 history messages, got %d", len(historyMessages))
+	}
+
+	transcript := buildOpenAIHistoryTranscript(historyMessages)
+	if !strings.Contains(transcript, "first user turn") {
+		t.Fatalf("expected user history in transcript, got %s", transcript)
+	}
+	if !strings.Contains(transcript, "<tool_calls>") {
+		t.Fatalf("expected assistant tool_calls in transcript, got %s", transcript)
+	}
+	if !strings.Contains(transcript, "tool_call_id=call-1") {
+		t.Fatalf("expected tool call id in transcript, got %s", transcript)
+	}
+	if strings.Contains(transcript, "hidden reasoning") {
+		t.Fatalf("did not expect hidden reasoning in transcript, got %s", transcript)
+	}
+
+	userIdx := strings.Index(transcript, "=== 1. USER ===")
+	assistantIdx := strings.Index(transcript, "=== 2. ASSISTANT ===")
+	toolIdx := strings.Index(transcript, "=== 3. TOOL ===")
+	if userIdx < 0 || assistantIdx < 0 || toolIdx < 0 {
+		t.Fatalf("expected ordered role sections, got %s", transcript)
+	}
+	if userIdx >= assistantIdx || assistantIdx >= toolIdx {
+		t.Fatalf("expected USER -> ASSISTANT -> TOOL order, got %s", transcript)
+	}
+
+	finalPrompt, _ := buildHistorySplitPrompt(promptMessages, nil, util.DefaultToolChoicePolicy(), false)
+	if !strings.Contains(finalPrompt, "latest user turn") {
+		t.Fatalf("expected latest user turn in final prompt, got %s", finalPrompt)
+	}
+	if strings.Contains(finalPrompt, "first user turn") {
+		t.Fatalf("expected earlier history to be removed from final prompt, got %s", finalPrompt)
+	}
+	if !strings.Contains(finalPrompt, "HISTORY.txt") {
+		t.Fatalf("expected history instruction in final prompt, got %s", finalPrompt)
+	}
+}
+
+func TestSplitOpenAIHistoryMessagesUsesLatestUserTurn(t *testing.T) {
+	toolCalls := []any{
+		map[string]any{
+			"name":      "search",
+			"arguments": map[string]any{"query": "docs"},
+		},
+	}
+	messages := []any{
+		map[string]any{"role": "system", "content": "system instructions"},
+		map[string]any{"role": "user", "content": "first user turn"},
+		map[string]any{
+			"role":       "assistant",
+			"content":    "",
+			"tool_calls": toolCalls,
+		},
+		map[string]any{
+			"role":         "tool",
+			"name":         "search",
+			"tool_call_id": "call-1",
+			"content":      "tool result",
+		},
+		map[string]any{"role": "user", "content": "middle user turn"},
+		map[string]any{
+			"role":    "assistant",
+			"content": "middle assistant turn",
+		},
+		map[string]any{"role": "user", "content": "latest user turn"},
+	}
+
+	promptMessages, historyMessages := splitOpenAIHistoryMessages(messages, 1)
+	if len(promptMessages) == 0 || len(historyMessages) == 0 {
+		t.Fatalf("expected both prompt and history messages, got prompt=%d history=%d", len(promptMessages), len(historyMessages))
+	}
+
+	promptText := buildOpenAIFinalPromptForSplitTest(promptMessages)
+	if !strings.Contains(promptText, "latest user turn") {
+		t.Fatalf("expected latest user turn in prompt, got %s", promptText)
+	}
+	if strings.Contains(promptText, "middle user turn") {
+		t.Fatalf("expected middle user turn to be split into history, got %s", promptText)
+	}
+
+	historyText := buildOpenAIHistoryTranscript(historyMessages)
+	if !strings.Contains(historyText, "middle user turn") {
+		t.Fatalf("expected middle user turn in HISTORY.txt, got %s", historyText)
+	}
+	if strings.Contains(historyText, "latest user turn") {
+		t.Fatalf("expected latest user turn to remain in prompt, got %s", historyText)
+	}
+}
+
+func buildOpenAIFinalPromptForSplitTest(messages []any) string {
+	prompt, _ := buildHistorySplitPrompt(messages, nil, util.DefaultToolChoicePolicy(), false)
+	return prompt
+}
+
+func TestApplyHistorySplitSkipsFirstTurn(t *testing.T) {
+	ds := &inlineUploadDSStub{}
+	h := &Handler{
+		Store: mockOpenAIConfig{
+			wideInput:           true,
+			historySplitEnabled: true,
+			historySplitTurns:   1,
+		},
+		DS: ds,
+	}
+	req := map[string]any{
+		"model": "deepseek-chat",
+		"messages": []any{
+			map[string]any{"role": "user", "content": "hello"},
+		},
+	}
+	stdReq, err := normalizeOpenAIChatRequest(h.Store, req, "")
+	if err != nil {
+		t.Fatalf("normalize failed: %v", err)
+	}
+
+	out, err := h.applyHistorySplit(context.Background(), &auth.RequestAuth{DeepSeekToken: "token"}, stdReq)
+	if err != nil {
+		t.Fatalf("apply history split failed: %v", err)
+	}
+	if len(ds.uploadCalls) != 0 {
+		t.Fatalf("expected no upload on first turn, got %d", len(ds.uploadCalls))
+	}
+	if out.FinalPrompt != stdReq.FinalPrompt {
+		t.Fatalf("expected prompt unchanged on first turn")
+	}
+	if len(out.RefFileIDs) != len(stdReq.RefFileIDs) {
+		t.Fatalf("expected ref files unchanged on first turn")
+	}
+}
+
+func TestChatCompletionsHistorySplitUploadsHistoryAndKeepsLatestPrompt(t *testing.T) {
+	ds := &inlineUploadDSStub{}
+	h := &Handler{
+		Store: mockOpenAIConfig{
+			wideInput:           true,
+			historySplitEnabled: true,
+			historySplitTurns:   1,
+		},
+		Auth: streamStatusAuthStub{},
+		DS:   ds,
+	}
+	reqBody, _ := json.Marshal(map[string]any{
+		"model":    "deepseek-chat",
+		"messages": historySplitTestMessages(),
+		"stream":   false,
+	})
+	req := httptest.NewRequest(http.MethodPost, "/v1/chat/completions", strings.NewReader(string(reqBody)))
+	req.Header.Set("Authorization", "Bearer direct-token")
+	req.Header.Set("Content-Type", "application/json")
+	rec := httptest.NewRecorder()
+
+	h.ChatCompletions(rec, req)
+
+	if rec.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d body=%s", rec.Code, rec.Body.String())
+	}
+	if len(ds.uploadCalls) != 1 {
+		t.Fatalf("expected 1 upload call, got %d", len(ds.uploadCalls))
+	}
+	upload := ds.uploadCalls[0]
+	if upload.Filename != "HISTORY.txt" {
+		t.Fatalf("unexpected upload filename: %q", upload.Filename)
+	}
+	if upload.ContentType != "text/plain; charset=utf-8" {
+		t.Fatalf("unexpected content type: %q", upload.ContentType)
+	}
+	if upload.Purpose != "assistants" {
+		t.Fatalf("unexpected purpose: %q", upload.Purpose)
+	}
+	historyText := string(upload.Data)
+	if !strings.Contains(historyText, "first user turn") || !strings.Contains(historyText, "tool result") {
+		t.Fatalf("expected older turns in HISTORY.txt, got %s", historyText)
+	}
+	if strings.Contains(historyText, "latest user turn") {
+		t.Fatalf("expected latest turn to remain in prompt, got %s", historyText)
+	}
+	if ds.completionReq == nil {
+		t.Fatal("expected completion payload to be captured")
+	}
+	promptText, _ := ds.completionReq["prompt"].(string)
+	if !strings.Contains(promptText, "latest user turn") {
+		t.Fatalf("expected latest turn in completion prompt, got %s", promptText)
+	}
+	if strings.Contains(promptText, "first user turn") {
+		t.Fatalf("expected historical turns removed from completion prompt, got %s", promptText)
+	}
+	if !strings.Contains(promptText, "HISTORY.txt") {
+		t.Fatalf("expected history instruction in completion prompt, got %s", promptText)
+	}
+	refIDs, _ := ds.completionReq["ref_file_ids"].([]any)
+	if len(refIDs) == 0 || refIDs[0] != "file-inline-1" {
+		t.Fatalf("expected uploaded history file to be first ref_file_id, got %#v", ds.completionReq["ref_file_ids"])
+	}
+}
+
+func TestResponsesHistorySplitUploadsHistoryAndKeepsLatestPrompt(t *testing.T) {
+	ds := &inlineUploadDSStub{}
+	h := &Handler{
+		Store: mockOpenAIConfig{
+			wideInput:           true,
+			historySplitEnabled: true,
+			historySplitTurns:   1,
+		},
+		Auth: streamStatusAuthStub{},
+		DS:   ds,
+	}
+	r := chi.NewRouter()
+	RegisterRoutes(r, h)
+	reqBody, _ := json.Marshal(map[string]any{
+		"model":    "deepseek-chat",
+		"messages": historySplitTestMessages(),
+		"stream":   false,
+	})
+	req := httptest.NewRequest(http.MethodPost, "/v1/responses", strings.NewReader(string(reqBody)))
+	req.Header.Set("Authorization", "Bearer direct-token")
+	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(ds.uploadCalls) != 1 {
+		t.Fatalf("expected 1 upload call, got %d", len(ds.uploadCalls))
+	}
+	if ds.completionReq == nil {
+		t.Fatal("expected completion payload to be captured")
+	}
+	promptText, _ := ds.completionReq["prompt"].(string)
+	if !strings.Contains(promptText, "latest user turn") {
+		t.Fatalf("expected latest turn in completion prompt, got %s", promptText)
+	}
+	if strings.Contains(promptText, "first user turn") {
+		t.Fatalf("expected historical turns removed from completion prompt, got %s", promptText)
+	}
+}
+
+func TestChatCompletionsHistorySplitUploadFailureReturnsInternalServerError(t *testing.T) {
+	ds := &inlineUploadDSStub{uploadErr: context.DeadlineExceeded}
+	h := &Handler{
+		Store: mockOpenAIConfig{
+			wideInput:           true,
+			historySplitEnabled: true,
+			historySplitTurns:   1,
+		},
+		Auth: streamStatusAuthStub{},
+		DS:   ds,
+	}
+	reqBody, _ := json.Marshal(map[string]any{
+		"model":    "deepseek-chat",
+		"messages": historySplitTestMessages(),
+		"stream":   false,
+	})
+	req := httptest.NewRequest(http.MethodPost, "/v1/chat/completions", strings.NewReader(string(reqBody)))
+	req.Header.Set("Authorization", "Bearer direct-token")
+	req.Header.Set("Content-Type", "application/json")
+	rec := httptest.NewRecorder()
+
+	h.ChatCompletions(rec, req)
+
+	if rec.Code != http.StatusInternalServerError {
+		t.Fatalf("expected 500, got %d body=%s", rec.Code, rec.Body.String())
+	}
+	if ds.completionReq != nil {
+		t.Fatalf("did not expect completion payload on upload failure")
+	}
+}

internal/adapter/openai/responses_handler.go

@@ -85,6 +85,11 @@ func (h *Handler) Responses(w http.ResponseWriter, r *http.Request) {
 		writeOpenAIError(w, http.StatusBadRequest, err.Error())
 		return
 	}
+	stdReq, err = h.applyHistorySplit(r.Context(), a, stdReq)
+	if err != nil {
+		writeOpenAIError(w, http.StatusInternalServerError, err.Error())
+		return
+	}
 
 	sessionID, err := h.DS.CreateSession(r.Context(), a, 3)
 	if err != nil {

internal/adapter/openai/standard_request.go

@@ -35,6 +35,7 @@ func normalizeOpenAIChatRequest(store ConfigReader, req map[string]any, traceID
 		ResolvedModel:  resolvedModel,
 		ResponseModel:  responseModel,
 		Messages:       messagesRaw,
+		ToolsRaw:       req["tools"],
 		FinalPrompt:    finalPrompt,
 		ToolNames:      toolNames,
 		ToolChoice:     toolPolicy,
@@ -90,6 +91,7 @@ func normalizeOpenAIResponsesRequest(store ConfigReader, req map[string]any, tra
 		ResolvedModel:  resolvedModel,
 		ResponseModel:  model,
 		Messages:       messagesRaw,
+		ToolsRaw:       req["tools"],
 		FinalPrompt:    finalPrompt,
 		ToolNames:      toolNames,
 		ToolChoice:     toolPolicy,

internal/adapter/openai/upstream_empty.go

@@ -2,7 +2,7 @@ package openai
 
 import "net/http"
 
-func shouldWriteUpstreamEmptyOutputError(text string, contentFilter bool) bool {
+func shouldWriteUpstreamEmptyOutputError(text string) bool {
 	return text == ""
 }
 
@@ -18,7 +18,7 @@ func upstreamEmptyOutputDetail(contentFilter bool, text, thinking string) (int,
 }
 
 func writeUpstreamEmptyOutputError(w http.ResponseWriter, text string, contentFilter bool) bool {
-	if !shouldWriteUpstreamEmptyOutputError(text, contentFilter) {
+	if !shouldWriteUpstreamEmptyOutputError(text) {
 		return false
 	}
 	status, message, code := upstreamEmptyOutputDetail(contentFilter, text, "")