refactor: replace history transcript format with numbered sections and rename upload file to HISTORY.txt

Author: CJackHwang

docs/prompt-compatibility.md

@@ -249,7 +249,7 @@ OpenAI 文件相关实现：
 
 兼容层现在只保留 `current_input_file` 这一种拆分方式；旧的 `history_split` 已废弃，只保留为兼容旧配置的字段，不再参与请求处理。
 
-- `current_input_file` 默认开启；它用于把“完整上下文”合并进 `history.txt` 上下文文件。当最新 user turn 的纯文本长度达到 `current_input_file.min_chars`（默认 `0`）时，兼容层会上传一个文件名为 `history.txt` 的上下文文件，并在 live prompt 中只保留一个中性的 user 消息要求模型直接回答最新请求，不再暴露文件名或要求模型读取本地文件。
+- `current_input_file` 默认开启；它用于把“完整上下文”合并进 `HISTORY.txt` 上下文文件。当最新 user turn 的纯文本长度达到 `current_input_file.min_chars`（默认 `0`）时，兼容层会上传一个文件名为 `HISTORY.txt` 的上下文文件。文件内容会先做 OpenAI 消息标准化，再序列化成按轮次编号的 `HISTORY.txt` 风格 transcript，带有 `# HISTORY.txt` 标题和 `=== N. ROLE ===` 分段；live prompt 中则只保留一个中性的 user 消息要求模型直接回答最新请求，不再暴露文件名或要求模型读取本地文件。
 - 如果 `current_input_file.enabled=false`，请求会直接透传，不上传任何拆分上下文文件。
 - 旧的 `history_split.enabled` / `history_split.trigger_after_turns` 会被读取进配置对象以保持兼容，但不会触发拆分上传，也不会影响 `current_input_file` 的默认开启。
 - 即使触发 `current_input_file` 后 live prompt 被缩短，对客户端回包里的上下文 token 统计，仍会沿用**拆分前的完整 prompt 语义**做计数，而不是按缩短后的占位 prompt 计算；否则会把真实上下文显著算小。
@@ -263,11 +263,24 @@ OpenAI 文件相关实现：
 - 旧历史拆分兼容壳：
   [internal/httpapi/openai/history/history_split.go](../internal/httpapi/openai/history/history_split.go)
 
-当前输入转文件启用并触发时，上传文件的真实文件名是 `history.txt`，文件内容是完整 `messages` 上下文；它仍会先用 OpenAI 消息标准化和 DeepSeek 角色标记序列化，并直接作为 `history.txt` 的纯文本内容上传（不再注入文件边界标签）：
+当前输入转文件启用并触发时，上传文件的真实文件名是 `HISTORY.txt`，文件内容是完整 `messages` 上下文；它仍会先用 OpenAI 消息标准化和 DeepSeek 角色标记序列化，再按轮次编号成 `HISTORY.txt` 风格的 transcript（不再注入文件边界标签）：
 
 ```text
-[uploaded filename]: history.txt
-<｜begin▁of▁sentence｜><｜System｜>...<｜User｜>...<｜Assistant｜>...<｜Tool｜>...<｜User｜>...
+[uploaded filename]: HISTORY.txt
+# HISTORY.txt
+Prior conversation history and tool progress.
+
+=== 1. SYSTEM ===
+...
+
+=== 2. USER ===
+...
+
+=== 3. ASSISTANT ===
+...
+
+=== 4. TOOL ===
+...
 ```
 
 开启后，请求的 live prompt 不再直接内联完整上下文，而是保留一个 user role 的短提示，提示模型基于已提供上下文直接回答最新请求；上传后的 `file_id` 会进入 `ref_file_ids`。
@@ -334,7 +347,7 @@ OpenAI 文件相关实现：
 
 - 大部分结构化语义被压进 `prompt`
 - 文件保持文件
-- 需要时把完整上下文拆进 `history.txt` 上下文文件
+- 需要时把完整上下文拆进 `HISTORY.txt` 上下文文件，并按轮次编号成 transcript
 
 ## 12. 修改时必须同步本文档的场景
 
@@ -347,7 +360,7 @@ OpenAI 文件相关实现：
 - tool result 注入方式变更
 - tool prompt 模板或 tool_choice 约束变更
 - inline 文件上传 / 文件引用收集规则变更
-- current input file 触发条件、上传格式、`history.txt` 包装格式变更
+- current input file 触发条件、上传格式、`HISTORY.txt` transcript 结构变更
 - 旧 `history_split` 兼容逻辑的读取、忽略或退化行为变更
 - completion payload 字段语义变更
 - Claude / Gemini 对这套统一语义的复用关系变更

internal/httpapi/openai/chat/chat_history_test.go

@@ -311,8 +311,8 @@ func TestChatCompletionsCurrentInputFilePersistsNeutralPrompt(t *testing.T) {
 	if len(ds.uploadCalls) != 1 {
 		t.Fatalf("expected current input upload to happen, got %d", len(ds.uploadCalls))
 	}
-	if ds.uploadCalls[0].Filename != "history.txt" {
-		t.Fatalf("expected history.txt upload, got %q", ds.uploadCalls[0].Filename)
+	if ds.uploadCalls[0].Filename != "HISTORY.txt" {
+		t.Fatalf("expected HISTORY.txt upload, got %q", ds.uploadCalls[0].Filename)
 	}
 	if full.HistoryText != string(ds.uploadCalls[0].Data) {
 		t.Fatalf("expected uploaded current input file to be persisted in history text")

internal/httpapi/openai/history/current_input_file.go

@@ -62,7 +62,7 @@ func (s Service) ApplyCurrentInputFile(ctx context.Context, a *auth.RequestAuth,
 	stdReq.RefFileIDs = prependUniqueRefFileID(stdReq.RefFileIDs, fileID)
 	stdReq.FinalPrompt, stdReq.ToolNames = promptcompat.BuildOpenAIPrompt(messages, stdReq.ToolsRaw, "", stdReq.ToolChoice, stdReq.Thinking)
 	// Token accounting must reflect the actual downstream context:
-	// the uploaded history.txt file content + the neutral live prompt.
+	// the uploaded HISTORY.txt file content + the neutral live prompt.
 	stdReq.PromptTokenText = fileText + "\n" + stdReq.FinalPrompt
 	return stdReq, nil
 }

internal/httpapi/openai/history_split_test.go

@@ -61,26 +61,33 @@ func (streamStatusManagedAuthStub) DetermineCaller(_ *http.Request) (*auth.Reque
 
 func (streamStatusManagedAuthStub) Release(_ *auth.RequestAuth) {}
 
-func TestBuildOpenAICurrentInputContextTranscriptUsesInjectedFileWrapper(t *testing.T) {
+func TestBuildOpenAICurrentInputContextTranscriptUsesNumberedHistorySections(t *testing.T) {
 	_, historyMessages := splitOpenAIHistoryMessages(historySplitTestMessages(), 1)
 	transcript := buildOpenAICurrentInputContextTranscript(historyMessages)
 
 	if strings.Contains(transcript, "[file content end]") || strings.Contains(transcript, "[file content begin]") || strings.Contains(transcript, "[file name]:") {
-		t.Fatalf("expected plain transcript without file wrapper tags, got %q", transcript)
-	}
-	if !strings.Contains(transcript, "<｜begin▁of▁sentence｜>") {
-		t.Fatalf("expected serialized conversation markers, got %q", transcript)
-	}
-	if !strings.Contains(transcript, "first user turn") || !strings.Contains(transcript, "tool result") {
-		t.Fatalf("expected historical turns preserved, got %q", transcript)
-	}
-	if !strings.Contains(transcript, "[reasoning_content]") || !strings.Contains(transcript, "hidden reasoning") {
-		t.Fatalf("expected reasoning block preserved, got %q", transcript)
-	}
-	if !strings.Contains(transcript, "<|DSML|tool_calls>") {
-		t.Fatalf("expected tool calls preserved, got %q", transcript)
+		t.Fatalf("expected transcript without file wrapper tags, got %q", transcript)
+	}
+	if !strings.Contains(transcript, "# HISTORY.txt") {
+		t.Fatalf("expected history transcript header, got %q", transcript)
+	}
+	if !strings.Contains(transcript, "Prior conversation history and tool progress.") {
+		t.Fatalf("expected history transcript description, got %q", transcript)
+	}
+	for _, want := range []string{
+		"=== 1. USER ===",
+		"=== 2. ASSISTANT ===",
+		"=== 3. TOOL ===",
+		"first user turn",
+		"tool result",
+		"[reasoning_content]",
+		"hidden reasoning",
+		"<|DSML|tool_calls>",
+	} {
+		if !strings.Contains(transcript, want) {
+			t.Fatalf("expected transcript to contain %q, got %q", want, transcript)
+		}
 	}
-
 }
 
 func TestSplitOpenAIHistoryMessagesUsesLatestUserTurn(t *testing.T) {
@@ -243,7 +250,7 @@ func TestApplyCurrentInputFileDisabledPassThrough(t *testing.T) {
 	}
 }
 
-func TestApplyCurrentInputFileUploadsFirstTurnWithInjectedWrapper(t *testing.T) {
+func TestApplyCurrentInputFileUploadsFirstTurnWithNumberedHistoryTranscript(t *testing.T) {
 	ds := &inlineUploadDSStub{}
 	h := &openAITestSurface{
 		Store: mockOpenAIConfig{
@@ -273,15 +280,21 @@ func TestApplyCurrentInputFileUploadsFirstTurnWithInjectedWrapper(t *testing.T)
 		t.Fatalf("expected 1 current input upload, got %d", len(ds.uploadCalls))
 	}
 	upload := ds.uploadCalls[0]
-	if upload.Filename != "history.txt" {
+	if upload.Filename != "HISTORY.txt" {
 		t.Fatalf("unexpected upload filename: %q", upload.Filename)
 	}
 	uploadedText := string(upload.Data)
 	if strings.Contains(uploadedText, "[file content end]") || strings.Contains(uploadedText, "[file content begin]") || strings.Contains(uploadedText, "[file name]:") {
 		t.Fatalf("expected uploaded transcript without file wrapper tags, got %q", uploadedText)
 	}
-	if !strings.Contains(uploadedText, "<｜begin▁of▁sentence｜><｜User｜>first turn content that is long enough") {
-		t.Fatalf("expected serialized current user turn markers, got %q", uploadedText)
+	for _, want := range []string{
+		"# HISTORY.txt",
+		"=== 1. USER ===",
+		"first turn content that is long enough",
+	} {
+		if !strings.Contains(uploadedText, want) {
+			t.Fatalf("expected uploaded transcript to contain %q, got %q", want, uploadedText)
+		}
 	}
 	if !strings.Contains(uploadedText, promptcompat.ThinkingInjectionMarker) {
 		t.Fatalf("expected thinking injection in current input file, got %q", uploadedText)
@@ -290,7 +303,7 @@ func TestApplyCurrentInputFileUploadsFirstTurnWithInjectedWrapper(t *testing.T)
 	if strings.Contains(out.FinalPrompt, "first turn content that is long enough") {
 		t.Fatalf("expected current input text to be replaced in live prompt, got %s", out.FinalPrompt)
 	}
-	if strings.Contains(out.FinalPrompt, "CURRENT_USER_INPUT.txt") || strings.Contains(out.FinalPrompt, "history.txt") || strings.Contains(out.FinalPrompt, "Read that file") {
+	if strings.Contains(out.FinalPrompt, "CURRENT_USER_INPUT.txt") || strings.Contains(out.FinalPrompt, "history.txt") || strings.Contains(out.FinalPrompt, "HISTORY.txt") || strings.Contains(out.FinalPrompt, "Read that file") {
 		t.Fatalf("expected live prompt not to instruct file reads, got %s", out.FinalPrompt)
 	}
 	if !strings.Contains(out.FinalPrompt, "Answer the latest user request directly.") {
@@ -302,6 +315,9 @@ func TestApplyCurrentInputFileUploadsFirstTurnWithInjectedWrapper(t *testing.T)
 	if !strings.Contains(out.PromptTokenText, "first turn content that is long enough") {
 		t.Fatalf("expected prompt token text to preserve original full context, got %q", out.PromptTokenText)
 	}
+	if !strings.Contains(out.PromptTokenText, "# HISTORY.txt") || !strings.Contains(out.PromptTokenText, "=== 1. USER ===") {
+		t.Fatalf("expected prompt token text to include numbered history transcript, got %q", out.PromptTokenText)
+	}
 }
 
 func TestApplyCurrentInputFilePreservesFullContextPromptForTokenCounting(t *testing.T) {
@@ -337,7 +353,10 @@ func TestApplyCurrentInputFilePreservesFullContextPromptForTokenCounting(t *test
 		t.Fatalf("expected prompt token text to contain file context with full conversation, got %q", out.PromptTokenText)
 	}
 	if strings.Contains(out.PromptTokenText, "[file content end]") || strings.Contains(out.PromptTokenText, "[file name]:") {
-		t.Fatalf("expected prompt token text to use raw transcript without wrapper tags, got %q", out.PromptTokenText)
+		t.Fatalf("expected prompt token text to omit file wrapper tags, got %q", out.PromptTokenText)
+	}
+	if !strings.Contains(out.PromptTokenText, "# HISTORY.txt") || !strings.Contains(out.PromptTokenText, "=== 1. SYSTEM ===") {
+		t.Fatalf("expected prompt token text to include numbered history transcript, got %q", out.PromptTokenText)
 	}
 	if !strings.Contains(out.PromptTokenText, "Answer the latest user request directly.") {
 		t.Fatalf("expected prompt token text to also include neutral live prompt, got %q", out.PromptTokenText)
@@ -378,16 +397,16 @@ func TestApplyCurrentInputFileUploadsFullContextFile(t *testing.T) {
 		t.Fatalf("expected one current input upload, got %d", len(ds.uploadCalls))
 	}
 	upload := ds.uploadCalls[0]
-	if upload.Filename != "history.txt" {
-		t.Fatalf("expected history.txt upload, got %q", upload.Filename)
+	if upload.Filename != "HISTORY.txt" {
+		t.Fatalf("expected HISTORY.txt upload, got %q", upload.Filename)
 	}
 	uploadedText := string(upload.Data)
-	for _, want := range []string{"system instructions", "first user turn", "hidden reasoning", "tool result", "latest user turn", promptcompat.ThinkingInjectionMarker} {
+	for _, want := range []string{"# HISTORY.txt", "=== 1. SYSTEM ===", "=== 2. USER ===", "=== 3. ASSISTANT ===", "=== 4. TOOL ===", "=== 5. USER ===", "system instructions", "first user turn", "hidden reasoning", "tool result", "latest user turn", promptcompat.ThinkingInjectionMarker} {
 		if !strings.Contains(uploadedText, want) {
 			t.Fatalf("expected full context file to contain %q, got %q", want, uploadedText)
 		}
 	}
-	if strings.Contains(out.FinalPrompt, "first user turn") || strings.Contains(out.FinalPrompt, "latest user turn") || strings.Contains(out.FinalPrompt, "CURRENT_USER_INPUT.txt") || strings.Contains(out.FinalPrompt, "history.txt") || strings.Contains(out.FinalPrompt, "Read that file") {
+	if strings.Contains(out.FinalPrompt, "first user turn") || strings.Contains(out.FinalPrompt, "latest user turn") || strings.Contains(out.FinalPrompt, "CURRENT_USER_INPUT.txt") || strings.Contains(out.FinalPrompt, "history.txt") || strings.Contains(out.FinalPrompt, "HISTORY.txt") || strings.Contains(out.FinalPrompt, "Read that file") {
 		t.Fatalf("expected live prompt to use only a neutral continuation instruction, got %s", out.FinalPrompt)
 	}
 	if !strings.Contains(out.FinalPrompt, "Answer the latest user request directly.") {
@@ -423,6 +442,9 @@ func TestApplyCurrentInputFileCarriesHistoryText(t *testing.T) {
 	if out.HistoryText != string(ds.uploadCalls[0].Data) {
 		t.Fatalf("expected current input file flow to preserve uploaded text in history, got %q", out.HistoryText)
 	}
+	if !strings.Contains(out.HistoryText, "# HISTORY.txt") || !strings.Contains(out.HistoryText, "=== 1. SYSTEM ===") {
+		t.Fatalf("expected history text to use numbered transcript format, got %q", out.HistoryText)
+	}
 }
 
 func TestChatCompletionsCurrentInputFileUploadsContextAndKeepsNeutralPrompt(t *testing.T) {
@@ -454,15 +476,18 @@ func TestChatCompletionsCurrentInputFileUploadsContextAndKeepsNeutralPrompt(t *t
 		t.Fatalf("expected 1 upload call, got %d", len(ds.uploadCalls))
 	}
 	upload := ds.uploadCalls[0]
-	if upload.Filename != "history.txt" {
+	if upload.Filename != "HISTORY.txt" {
 		t.Fatalf("unexpected upload filename: %q", upload.Filename)
 	}
 	if upload.Purpose != "assistants" {
 		t.Fatalf("unexpected purpose: %q", upload.Purpose)
 	}
 	historyText := string(upload.Data)
 	if strings.Contains(historyText, "[file content end]") || strings.Contains(historyText, "[file content begin]") || strings.Contains(historyText, "[file name]:") {
-		t.Fatalf("expected plain history transcript without wrapper tags, got %s", historyText)
+		t.Fatalf("expected history transcript without file wrapper tags, got %s", historyText)
+	}
+	if !strings.Contains(historyText, "# HISTORY.txt") || !strings.Contains(historyText, "=== 1. SYSTEM ===") {
+		t.Fatalf("expected history transcript to use numbered sections, got %s", historyText)
 	}
 	if !strings.Contains(historyText, "latest user turn") {
 		t.Fatalf("expected full context to include latest turn, got %s", historyText)
@@ -523,6 +548,10 @@ func TestResponsesCurrentInputFileUploadsContextAndKeepsNeutralPrompt(t *testing
 	if len(ds.uploadCalls) != 1 {
 		t.Fatalf("expected 1 upload call, got %d", len(ds.uploadCalls))
 	}
+	historyText := string(ds.uploadCalls[0].Data)
+	if !strings.Contains(historyText, "# HISTORY.txt") || !strings.Contains(historyText, "=== 1. SYSTEM ===") {
+		t.Fatalf("expected uploaded history text to use numbered transcript format, got %s", historyText)
+	}
 	if ds.completionReq == nil {
 		t.Fatal("expected completion payload to be captured")
 	}
@@ -669,6 +698,10 @@ func TestCurrentInputFileWorksAcrossAutoDeleteModes(t *testing.T) {
 			if len(ds.uploadCalls) != 1 {
 				t.Fatalf("expected current input upload for mode=%s, got %d", mode, len(ds.uploadCalls))
 			}
+			historyText := string(ds.uploadCalls[0].Data)
+			if !strings.Contains(historyText, "# HISTORY.txt") || !strings.Contains(historyText, "=== 1. SYSTEM ===") {
+				t.Fatalf("expected uploaded history text to use numbered transcript format, got %s", historyText)
+			}
 			if ds.completionReq == nil {
 				t.Fatalf("expected completion payload for mode=%s", mode)
 			}

internal/promptcompat/history_transcript.go

@@ -1,35 +1,108 @@
 package promptcompat
 
 import (
+	"fmt"
 	"strings"
-
-	"ds2api/internal/prompt"
 )
 
-const CurrentInputContextFilename = "history.txt"
+const CurrentInputContextFilename = "HISTORY.txt"
+
+const historyTranscriptTitle = "# HISTORY.txt"
+const historyTranscriptSummary = "Prior conversation history and tool progress."
 
 func BuildOpenAIHistoryTranscript(messages []any) string {
-	return buildOpenAIInjectedFileTranscript(messages)
+	return buildOpenAIHistoryTranscript(messages)
 }
 
 func BuildOpenAICurrentUserInputTranscript(text string) string {
 	if strings.TrimSpace(text) == "" {
 		return ""
 	}
-	return BuildOpenAICurrentInputContextTranscript([]any{
+	return buildOpenAIHistoryTranscript([]any{
 		map[string]any{"role": "user", "content": text},
 	})
 }
 
 func BuildOpenAICurrentInputContextTranscript(messages []any) string {
-	return buildOpenAIInjectedFileTranscript(messages)
+	return buildOpenAIHistoryTranscript(messages)
 }
 
-func buildOpenAIInjectedFileTranscript(messages []any) string {
-	normalized := NormalizeOpenAIMessagesForPrompt(messages, "")
-	transcript := strings.TrimSpace(prompt.MessagesPrepare(normalized))
+func buildOpenAIHistoryTranscript(messages []any) string {
+	if len(messages) == 0 {
+		return ""
+	}
+	var b strings.Builder
+	b.WriteString(historyTranscriptTitle)
+	b.WriteString("\n")
+	b.WriteString(historyTranscriptSummary)
+	b.WriteString("\n\n")
+
+	entry := 0
+	for _, raw := range messages {
+		msg, ok := raw.(map[string]any)
+		if !ok {
+			continue
+		}
+		role := normalizeOpenAIRoleForPrompt(strings.ToLower(strings.TrimSpace(asString(msg["role"]))))
+		content := strings.TrimSpace(buildOpenAIHistoryEntry(role, msg))
+		if content == "" {
+			continue
+		}
+		entry++
+		fmt.Fprintf(&b, "=== %d. %s ===\n%s\n\n", entry, strings.ToUpper(roleLabelForHistory(role)), content)
+	}
+
+	transcript := strings.TrimSpace(b.String())
 	if transcript == "" {
 		return ""
 	}
-	return transcript
+	return transcript + "\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 "system", "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
+	}
 }