增加不同上下文模式

README.MD

@@ -284,7 +284,7 @@ go run ./cmd/ds2api
 - `history_split`：轮次拆分策略；默认关闭，开启后默认从第二轮开始将旧历史上传为 `HISTORY.txt`。
 - `current_input_file`：独立拆分策略；默认开启且阈值为 `0`，触发时将完整上下文合并上传为隐藏上下文文件，并跳过 `HISTORY.txt`。
 - `history_split` 与 `current_input_file` 互斥，最多启用一个；两者都关闭时请求直接透传。
-- `thinking_injection`：默认开启；在最新 user 消息末尾追加思考格式增强提示，提高工具调用前的思考结构稳定性。
+- `thinking_injection`：默认开启；在最新 user 消息末尾追加思考格式增强提示，提高工具调用前的思考结构稳定性；`prompt` 留空时使用内置默认提示词。
 
 环境变量完整列表见 [部署指南](docs/DEPLOY.md)，接口鉴权规则见 [API.md](API.md#鉴权规则)。
 

config.example.json

@@ -59,7 +59,8 @@
     "min_chars": 0
   },
   "thinking_injection": {
-    "enabled": true
+    "enabled": true,
+    "prompt": ""
   },
   "embeddings": {
     "provider": "deterministic"

docs/prompt-compatibility.md

@@ -103,7 +103,7 @@ DS2API 当前的核心思路，不是把客户端传来的 `messages`、`tools`
 
 ## 5. prompt 是怎么拼出来的
 
-OpenAI Chat / Responses 在标准化后、history split / current input file 之前，会默认执行 `thinking_injection` 增强。它参考 DeepSeek V4 “把控制指令放在 user 消息末尾更稳定”的用法，在最新 user message 后追加 `【思维链格式要求】...`，要求模型在 `<think>` 内按分析、构思、工具调用、XML 工具格式回顾这几个阶段组织思考。该开关默认启用，可通过 `thinking_injection.enabled=false` 关闭。
+OpenAI Chat / Responses 在标准化后、history split / current input file 之前，会默认执行 `thinking_injection` 增强。它参考 DeepSeek V4 “把控制指令放在 user 消息末尾更稳定”的用法，在最新 user message 后追加思考格式提示词，默认内容以 `【思维链格式要求】...` 开头，要求模型在 `<think>` 内按分析、构思、工具调用、XML 工具格式回顾这几个阶段组织思考。该开关默认启用，可通过 `thinking_injection.enabled=false` 关闭；也可以通过 `thinking_injection.prompt` 自定义提示词，留空时使用内置默认提示词。
 
 这段增强属于 prompt 可见上下文：
 

internal/config/codec.go

@@ -51,7 +51,7 @@ func (c Config) MarshalJSON() ([]byte, error) {
 	if c.CurrentInputFile.Enabled != nil || c.CurrentInputFile.MinChars != 0 {
 		m["current_input_file"] = c.CurrentInputFile
 	}
-	if c.ThinkingInjection.Enabled != nil {
+	if c.ThinkingInjection.Enabled != nil || strings.TrimSpace(c.ThinkingInjection.Prompt) != "" {
 		m["thinking_injection"] = c.ThinkingInjection
 	}
 	if c.VercelSyncHash != "" {
@@ -177,6 +177,7 @@ func (c Config) Clone() Config {
 		},
 		ThinkingInjection: ThinkingInjectionConfig{
 			Enabled: cloneBoolPtr(c.ThinkingInjection.Enabled),
+			Prompt:  c.ThinkingInjection.Prompt,
 		},
 		VercelSyncHash:   c.VercelSyncHash,
 		VercelSyncTime:   c.VercelSyncTime,

internal/config/config.go

@@ -184,5 +184,6 @@ type CurrentInputFileConfig struct {
 }
 
 type ThinkingInjectionConfig struct {
-	Enabled *bool `json:"enabled,omitempty"`
+	Enabled *bool  `json:"enabled,omitempty"`
+	Prompt  string `json:"prompt,omitempty"`
 }

internal/config/store_accessors.go

@@ -208,3 +208,9 @@ func (s *Store) ThinkingInjectionEnabled() bool {
 	}
 	return *s.cfg.ThinkingInjection.Enabled
 }
+
+func (s *Store) ThinkingInjectionPrompt() string {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return strings.TrimSpace(s.cfg.ThinkingInjection.Prompt)
+}

internal/config/store_accessors_test.go

@@ -83,4 +83,9 @@ func TestStoreThinkingInjectionAccessors(t *testing.T) {
 	if store.ThinkingInjectionEnabled() {
 		t.Fatal("expected thinking injection disabled by explicit config")
 	}
+
+	store.cfg.ThinkingInjection.Prompt = "  custom thinking prompt  "
+	if got := store.ThinkingInjectionPrompt(); got != "custom thinking prompt" {
+		t.Fatalf("thinking injection prompt=%q want custom thinking prompt", got)
+	}
 }

internal/httpapi/admin/handler_settings_test.go

@@ -75,6 +75,12 @@ func TestGetSettingsIncludesHistorySplitDefaults(t *testing.T) {
 	if got := boolFrom(thinkingInjection["enabled"]); !got {
 		t.Fatalf("expected thinking_injection.enabled=true, body=%v", body)
 	}
+	if got, _ := thinkingInjection["prompt"].(string); got != "" {
+		t.Fatalf("expected empty custom thinking prompt, got %q body=%v", got, body)
+	}
+	if got, _ := thinkingInjection["default_prompt"].(string); got == "" {
+		t.Fatalf("expected default thinking prompt, body=%v", body)
+	}
 }
 
 func TestUpdateSettingsValidation(t *testing.T) {
@@ -264,6 +270,7 @@ func TestUpdateSettingsThinkingInjection(t *testing.T) {
 	payload := map[string]any{
 		"thinking_injection": map[string]any{
 			"enabled": false,
+			"prompt":  " custom thinking prompt ",
 		},
 	}
 	b, _ := json.Marshal(payload)
@@ -280,6 +287,9 @@ func TestUpdateSettingsThinkingInjection(t *testing.T) {
 	if h.Store.ThinkingInjectionEnabled() {
 		t.Fatal("expected thinking injection accessor to reflect disabled config")
 	}
+	if got := h.Store.ThinkingInjectionPrompt(); got != "custom thinking prompt" {
+		t.Fatalf("expected custom thinking prompt, got %q", got)
+	}
 }
 
 func TestUpdateSettingsAutoDeleteMode(t *testing.T) {

internal/httpapi/admin/settings/handler_settings_parse.go

@@ -199,6 +199,9 @@ func parseSettingsUpdateRequest(req map[string]any) (*config.AdminConfig, *confi
 			b := boolFrom(v)
 			cfg.Enabled = &b
 		}
+		if v, exists := raw["prompt"]; exists {
+			cfg.Prompt = strings.TrimSpace(fmt.Sprintf("%v", v))
+		}
 		thinkingInjCfg = cfg
 	}
 

internal/httpapi/admin/settings/handler_settings_read.go

@@ -6,6 +6,7 @@ import (
 
 	authn "ds2api/internal/auth"
 	"ds2api/internal/config"
+	"ds2api/internal/promptcompat"
 )
 
 func (h *Handler) getSettings(w http.ResponseWriter, _ *http.Request) {
@@ -39,7 +40,9 @@ func (h *Handler) getSettings(w http.ResponseWriter, _ *http.Request) {
 			"min_chars": h.Store.CurrentInputFileMinChars(),
 		},
 		"thinking_injection": map[string]any{
-			"enabled": h.Store.ThinkingInjectionEnabled(),
+			"enabled":        h.Store.ThinkingInjectionEnabled(),
+			"prompt":         h.Store.ThinkingInjectionPrompt(),
+			"default_prompt": promptcompat.DefaultThinkingInjectionPrompt,
 		},
 		"model_aliases":     snap.ModelAliases,
 		"env_backed":        h.Store.IsEnvBacked(),

internal/httpapi/admin/settings/handler_settings_write.go

@@ -89,6 +89,7 @@ func (h *Handler) updateSettings(w http.ResponseWriter, r *http.Request) {
 		}
 		if thinkingInjCfg != nil {
 			c.ThinkingInjection.Enabled = thinkingInjCfg.Enabled
+			c.ThinkingInjection.Prompt = thinkingInjCfg.Prompt
 		}
 		if aliasMap != nil {
 			c.ModelAliases = aliasMap

internal/httpapi/admin/shared/deps.go

@@ -38,6 +38,7 @@ type ConfigStore interface {
 	CurrentInputFileEnabled() bool
 	CurrentInputFileMinChars() int
 	ThinkingInjectionEnabled() bool
+	ThinkingInjectionPrompt() string
 	CompatStripReferenceMarkers() bool
 	AutoDeleteSessions() bool
 }

internal/httpapi/openai/chat/test_helpers_test.go

@@ -23,6 +23,7 @@ type mockOpenAIConfig struct {
 	currentInputEnabled bool
 	currentInputMin     int
 	thinkingInjection   *bool
+	thinkingPrompt      string
 }
 
 func (m mockOpenAIConfig) ModelAliases() map[string]string { return m.aliases }
@@ -58,6 +59,7 @@ func (m mockOpenAIConfig) ThinkingInjectionEnabled() bool {
 	}
 	return *m.thinkingInjection
 }
+func (m mockOpenAIConfig) ThinkingInjectionPrompt() string { return m.thinkingPrompt }
 
 type streamStatusAuthStub struct{}
 

internal/httpapi/openai/deps_injection_test.go

@@ -19,6 +19,7 @@ type mockOpenAIConfig struct {
 	currentInputEnabled bool
 	currentInputMin     int
 	thinkingInjection   *bool
+	thinkingPrompt      string
 }
 
 func (m mockOpenAIConfig) ModelAliases() map[string]string { return m.aliases }
@@ -54,6 +55,7 @@ func (m mockOpenAIConfig) ThinkingInjectionEnabled() bool {
 	}
 	return *m.thinkingInjection
 }
+func (m mockOpenAIConfig) ThinkingInjectionPrompt() string { return m.thinkingPrompt }
 
 func TestNormalizeOpenAIChatRequestWithConfigInterface(t *testing.T) {
 	cfg := mockOpenAIConfig{

internal/httpapi/openai/history_split_test.go

@@ -183,6 +183,36 @@ func TestApplyThinkingInjectionAppendsLatestUserPrompt(t *testing.T) {
 	}
 }
 
+func TestApplyThinkingInjectionUsesCustomPrompt(t *testing.T) {
+	ds := &inlineUploadDSStub{}
+	h := &openAITestSurface{
+		Store: mockOpenAIConfig{
+			wideInput:         true,
+			thinkingInjection: boolPtr(true),
+			thinkingPrompt:    "custom thinking format",
+		},
+		DS: ds,
+	}
+	req := map[string]any{
+		"model": "deepseek-v4-flash",
+		"messages": []any{
+			map[string]any{"role": "user", "content": "hello"},
+		},
+	}
+	stdReq, err := promptcompat.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 thinking injection failed: %v", err)
+	}
+	if !strings.Contains(out.FinalPrompt, "hello\n\ncustom thinking format") {
+		t.Fatalf("expected custom thinking injection after latest user message, got %s", out.FinalPrompt)
+	}
+}
+
 func TestApplyHistorySplitDirectPassThroughWhenBothSplitsDisabled(t *testing.T) {
 	ds := &inlineUploadDSStub{}
 	h := &openAITestSurface{

internal/httpapi/openai/shared/deps.go

@@ -48,6 +48,7 @@ type ConfigReader interface {
 	CurrentInputFileEnabled() bool
 	CurrentInputFileMinChars() int
 	ThinkingInjectionEnabled() bool
+	ThinkingInjectionPrompt() string
 }
 
 type Deps struct {

internal/httpapi/openai/shared/thinking_injection.go

@@ -6,7 +6,7 @@ func ApplyThinkingInjection(store ConfigReader, stdReq promptcompat.StandardRequ
 	if store == nil || !store.ThinkingInjectionEnabled() || !stdReq.Thinking {
 		return stdReq
 	}
-	messages, changed := promptcompat.AppendThinkingInjectionToLatestUser(stdReq.Messages)
+	messages, changed := promptcompat.AppendThinkingInjectionPromptToLatestUser(stdReq.Messages, store.ThinkingInjectionPrompt())
 	if !changed {
 		return stdReq
 	}

internal/promptcompat/thinking_injection.go

@@ -12,9 +12,17 @@ const (
 )
 
 func AppendThinkingInjectionToLatestUser(messages []any) ([]any, bool) {
+	return AppendThinkingInjectionPromptToLatestUser(messages, "")
+}
+
+func AppendThinkingInjectionPromptToLatestUser(messages []any, injectionPrompt string) ([]any, bool) {
 	if len(messages) == 0 {
 		return messages, false
 	}
+	injectionPrompt = strings.TrimSpace(injectionPrompt)
+	if injectionPrompt == "" {
+		injectionPrompt = DefaultThinkingInjectionPrompt
+	}
 	for i := len(messages) - 1; i >= 0; i-- {
 		msg, ok := messages[i].(map[string]any)
 		if !ok {
@@ -24,10 +32,11 @@ func AppendThinkingInjectionToLatestUser(messages []any) ([]any, bool) {
 			continue
 		}
 		content := msg["content"]
-		if strings.Contains(NormalizeOpenAIContentForPrompt(content), ThinkingInjectionMarker) {
+		normalizedContent := NormalizeOpenAIContentForPrompt(content)
+		if strings.Contains(normalizedContent, ThinkingInjectionMarker) || strings.Contains(normalizedContent, injectionPrompt) {
 			return messages, false
 		}
-		updatedContent := appendThinkingInjectionToContent(content)
+		updatedContent := appendThinkingInjectionToContent(content, injectionPrompt)
 		out := append([]any(nil), messages...)
 		cloned := make(map[string]any, len(msg))
 		for k, v := range msg {
@@ -40,20 +49,20 @@ func AppendThinkingInjectionToLatestUser(messages []any) ([]any, bool) {
 	return messages, false
 }
 
-func appendThinkingInjectionToContent(content any) any {
+func appendThinkingInjectionToContent(content any, injectionPrompt string) any {
 	switch x := content.(type) {
 	case string:
-		return appendTextBlock(x, DefaultThinkingInjectionPrompt)
+		return appendTextBlock(x, injectionPrompt)
 	case []any:
 		out := append([]any(nil), x...)
 		out = append(out, map[string]any{
 			"type": "text",
-			"text": DefaultThinkingInjectionPrompt,
+			"text": injectionPrompt,
 		})
 		return out
 	default:
 		text := NormalizeOpenAIContentForPrompt(content)
-		return appendTextBlock(text, DefaultThinkingInjectionPrompt)
+		return appendTextBlock(text, injectionPrompt)
 	}
 }
 

internal/promptcompat/thinking_injection_test.go

@@ -51,6 +51,21 @@ func TestAppendThinkingInjectionToLatestUserArrayContent(t *testing.T) {
 	}
 }
 
+func TestAppendThinkingInjectionToLatestUserCustomPrompt(t *testing.T) {
+	messages := []any{
+		map[string]any{"role": "user", "content": "latest"},
+	}
+
+	out, changed := AppendThinkingInjectionPromptToLatestUser(messages, "custom thinking format")
+	if !changed {
+		t.Fatal("expected custom thinking injection to be appended")
+	}
+	content, _ := out[0].(map[string]any)["content"].(string)
+	if !strings.Contains(content, "latest\n\ncustom thinking format") {
+		t.Fatalf("expected custom injection after latest user text, got %q", content)
+	}
+}
+
 func TestAppendThinkingInjectionToLatestUserSkipsDuplicate(t *testing.T) {
 	messages := []any{
 		map[string]any{"role": "user", "content": "latest\n\n" + DefaultThinkingInjectionPrompt},

webui/src/features/settings/BehaviorSection.jsx

@@ -46,6 +46,23 @@ export default function BehaviorSection({ t, form, setForm }) {
                         <span className="text-xs text-muted-foreground block">{t('settings.thinkingInjectionDesc')}</span>
                     </div>
                 </label>
+                <label className="text-sm space-y-2 md:col-span-2">
+                    <span className="text-muted-foreground">{t('settings.thinkingInjectionPrompt')}</span>
+                    <textarea
+                        rows={5}
+                        value={form.thinking_injection?.prompt || ''}
+                        placeholder={form.thinking_injection?.default_prompt || ''}
+                        onChange={(e) => setForm((prev) => ({
+                            ...prev,
+                            thinking_injection: {
+                                ...prev.thinking_injection,
+                                prompt: e.target.value,
+                            },
+                        }))}
+                        className="w-full bg-background border border-border rounded-lg px-3 py-2 resize-y min-h-32"
+                    />
+                    <p className="text-xs text-muted-foreground">{t('settings.thinkingInjectionPromptHelp')}</p>
+                </label>
             </div>
         </div>
     )

webui/src/features/settings/useSettingsForm.js

@@ -19,7 +19,7 @@ const DEFAULT_FORM = {
     auto_delete: { mode: 'none' },
     history_split: { enabled: false, trigger_after_turns: 1 },
     current_input_file: { enabled: true, min_chars: 0 },
-    thinking_injection: { enabled: true },
+    thinking_injection: { enabled: true, prompt: '', default_prompt: '' },
     model_aliases_text: '{}',
 }
 
@@ -84,6 +84,8 @@ function fromServerForm(data) {
         },
         thinking_injection: {
             enabled: data.thinking_injection?.enabled ?? true,
+            prompt: data.thinking_injection?.prompt || '',
+            default_prompt: data.thinking_injection?.default_prompt || '',
         },
         model_aliases_text: JSON.stringify(data.model_aliases || {}, null, 2),
     }
@@ -116,6 +118,7 @@ function toServerPayload(form) {
         },
         thinking_injection: {
             enabled: Boolean(form.thinking_injection?.enabled ?? true),
+            prompt: String(form.thinking_injection?.prompt || '').trim(),
         },
     }
 }

webui/src/locales/en.json

@@ -375,6 +375,8 @@
         "embeddingsProvider": "Embeddings provider",
         "thinkingInjectionEnabled": "Thinking format injection",
         "thinkingInjectionDesc": "Append a structured <think> checklist to the latest user message before prompt assembly.",
+        "thinkingInjectionPrompt": "Thinking format prompt",
+        "thinkingInjectionPromptHelp": "Leave empty to use the built-in default prompt shown as the input placeholder.",
         "historySplitTitle": "Context Split",
         "historySplitDesc": "Choose one context-splitting mode to avoid inlining very long prompts.",
         "historySplitEnabled": "Turn split (second turn by default)",

webui/src/locales/zh.json

@@ -375,6 +375,8 @@
         "embeddingsProvider": "Embeddings Provider",
         "thinkingInjectionEnabled": "思考格式注入",
         "thinkingInjectionDesc": "在组装 prompt 前，将结构化 <think> 检查清单追加到最新用户消息末尾。",
+        "thinkingInjectionPrompt": "思考格式提示词",
+        "thinkingInjectionPromptHelp": "留空时使用内置默认提示词；默认内容会显示在输入框占位文本中。",
         "historySplitTitle": "上下文拆分",
         "historySplitDesc": "选择一种上下文拆分方式，减少超长 prompt 直接内联。",
         "historySplitEnabled": "轮次拆分（默认第二轮）",