feat: 添加会话标题自动生成功能

- 后端：首次 AI 回复后自动从用户消息提取标题
- 后端：通过 WebSocket 推送 session_updated 事件
- 前端：useChat hook 处理标题更新事件
- 前端：Sidebar 组件实时更新会话标题显示

packages/desktop/src/App.tsx

@@ -2,7 +2,7 @@
  * App Component
  */
 
-import { useState, useEffect } from 'react';
+import { useState, useEffect, useCallback } from 'react';
 import {
   Sidebar,
   FileBrowser,
@@ -19,6 +19,7 @@ export function App() {
   const [isInitializing, setIsInitializing] = useState(true);
   const [showFileBrowser, setShowFileBrowser] = useState(false);
   const [showConfig, setShowConfig] = useState(false);
+  const [sessionTitleUpdate, setSessionTitleUpdate] = useState<{ sessionId: string; name: string } | null>(null);
 
   // 初始化：加载或创建会话
   useEffect(() => {
@@ -52,6 +53,11 @@ export function App() {
     setCurrentSessionId(session.id);
   };
 
+  // 会话标题更新回调
+  const handleSessionUpdated = useCallback((sessionId: string, name: string) => {
+    setSessionTitleUpdate({ sessionId, name });
+  }, []);
+
   if (isInitializing) {
     return (
       <div className="h-screen flex items-center justify-center bg-gray-900">
@@ -69,6 +75,7 @@ export function App() {
         currentSessionId={currentSessionId}
         onSelectSession={handleSelectSession}
         onCreateSession={handleCreateSession}
+        sessionTitleUpdate={sessionTitleUpdate}
       />
 
       <div className="flex-1 flex">
@@ -78,6 +85,7 @@ export function App() {
             <ChatPage
               key={currentSessionId}
               sessionId={currentSessionId}
+              onSessionUpdated={handleSessionUpdated}
               showFileBrowser={showFileBrowser}
               onToggleFileBrowser={() => setShowFileBrowser(!showFileBrowser)}
               onOpenConfig={() => setShowConfig(true)}

packages/desktop/src/pages/Chat.tsx

@@ -15,6 +15,7 @@ import {
 
 interface ChatPageProps {
   sessionId: string;
+  onSessionUpdated?: (sessionId: string, name: string) => void;
   // 工具栏按钮
   showFileBrowser?: boolean;
   onToggleFileBrowser?: () => void;
@@ -23,6 +24,7 @@ interface ChatPageProps {
 
 export function ChatPage({
   sessionId,
+  onSessionUpdated,
   showFileBrowser,
   onToggleFileBrowser,
   onOpenConfig,
@@ -39,6 +41,7 @@ export function ChatPage({
     onError: (error) => {
       console.error('Chat error:', error);
     },
+    onSessionUpdated,
   });
 
   const messagesEndRef = useRef<HTMLDivElement>(null);

packages/server/src/agent/adapter.ts

@@ -196,6 +196,20 @@ export async function processMessage(sessionId: string, content: string): Promis
       payload: assistantMessage,
     });
 
+    // 检查是否需要生成会话标题（首次对话完成后）
+    const session = sessionManager.get(sessionId);
+    const messages = sessionManager.getMessages(sessionId);
+    if (session && !session.name && messages.length === 2) {
+      // 首条用户消息 + 首条 AI 回复 = 2 条消息
+      const userMessage = messages.find(m => m.role === 'user');
+      if (userMessage) {
+        // 异步生成标题，不阻塞响应
+        generateSessionTitle(sessionId, userMessage.content, response).catch(err => {
+          console.error('[Agent] Failed to generate session title:', err);
+        });
+      }
+    }
+
     emitStatusEvent(sessionId, 'idle');
   } catch (error) {
     const errorMessage = error instanceof Error ? error.message : String(error);
@@ -247,3 +261,62 @@ export function getAgentStats(sessionId: string): {
     contextUsage: agent.getContextUsageFormatted(),
   };
 }
+
+// ============================================================================
+// 会话标题生成
+// ============================================================================
+
+/**
+ * 从用户消息中提取简短标题
+ * 使用简单的启发式方法，不依赖 LLM
+ */
+function extractTitleFromMessage(userMessage: string): string {
+  // 移除多余空白
+  const cleaned = userMessage.trim().replace(/\s+/g, ' ');
+
+  // 如果消息很短，直接使用
+  if (cleaned.length <= 30) {
+    return cleaned;
+  }
+
+  // 尝试提取第一句话
+  const firstSentence = cleaned.match(/^[^。！？.!?]+[。！？.!?]?/)?.[0] || cleaned;
+
+  // 如果第一句话也很长，截断
+  if (firstSentence.length > 40) {
+    return firstSentence.slice(0, 37) + '...';
+  }
+
+  return firstSentence;
+}
+
+/**
+ * 生成会话标题并更新
+ */
+async function generateSessionTitle(
+  sessionId: string,
+  userMessage: string,
+  _assistantResponse: string
+): Promise<void> {
+  const sessionManager = getSessionManager();
+
+  // 使用简单提取方式生成标题
+  const title = extractTitleFromMessage(userMessage);
+
+  // 更新会话标题
+  const updatedSession = await sessionManager.updateSessionName(sessionId, title);
+
+  if (updatedSession) {
+    // 广播标题更新事件
+    broadcastToSession(sessionId, {
+      type: 'session_updated',
+      sessionId,
+      payload: {
+        id: updatedSession.id,
+        name: updatedSession.name,
+      },
+    });
+
+    console.log(`[Agent] Session title generated: "${title}"`);
+  }
+}

packages/server/src/session/manager.ts

@@ -253,6 +253,22 @@ export class SessionManager {
     return fullMessage;
   }
 
+  /**
+   * 更新会话名称/标题
+   */
+  async updateSessionName(sessionId: string, name: string): Promise<Session | undefined> {
+    const session = this.sessions.get(sessionId);
+    if (!session) return undefined;
+
+    session.name = name;
+    session.updatedAt = new Date().toISOString();
+
+    // 持久化
+    await this.persist(sessionId);
+
+    return session;
+  }
+
   /**
    * 获取会话数量
    */

packages/server/src/types.ts

@@ -108,7 +108,8 @@ export interface ServerMessage {
     | 'tool_result'
     | 'done'
     | 'cancelled'
-    | 'error';
+    | 'error'
+    | 'session_updated';
   sessionId: string;
   payload?: unknown;
 }

packages/ui/src/components/Sidebar.tsx

@@ -19,6 +19,8 @@ interface SidebarProps {
   onCreateSession: (session: Session) => void;
   /** 是否启用响应式布局（移动端抽屉式菜单） */
   responsive?: boolean;
+  /** 会话标题更新事件（从 WebSocket 接收） */
+  sessionTitleUpdate?: { sessionId: string; name: string } | null;
 }
 
 export function Sidebar({
@@ -26,6 +28,7 @@ export function Sidebar({
   onSelectSession,
   onCreateSession,
   responsive = false,
+  sessionTitleUpdate,
 }: SidebarProps) {
   const [sessions, setSessions] = useState<Session[]>([]);
   const [isLoading, setIsLoading] = useState(false);
@@ -84,6 +87,19 @@ export function Sidebar({
     loadSessions();
   }, []);
 
+  // 处理会话标题更新
+  useEffect(() => {
+    if (sessionTitleUpdate) {
+      setSessions((prev) =>
+        prev.map((s) =>
+          s.id === sessionTitleUpdate.sessionId
+            ? { ...s, name: sessionTitleUpdate.name }
+            : s
+        )
+      );
+    }
+  }, [sessionTitleUpdate]);
+
   const handleOverlayClick = () => {
     setIsOpen(false);
   };

packages/ui/src/hooks/useChat.ts

@@ -11,6 +11,7 @@ interface UseChatOptions {
   sessionId: string;
   onError?: (error: Error) => void;
   onSessionNotFound?: () => void;
+  onSessionUpdated?: (sessionId: string, name: string) => void;
 }
 
 interface ChatState {
@@ -20,7 +21,7 @@ interface ChatState {
   streamingContent: string;
 }
 
-export function useChat({ sessionId, onError, onSessionNotFound }: UseChatOptions) {
+export function useChat({ sessionId, onError, onSessionNotFound, onSessionUpdated }: UseChatOptions) {
   const [state, setState] = useState<ChatState>({
     messages: [],
     isConnected: false,
@@ -38,8 +39,10 @@ export function useChat({ sessionId, onError, onSessionNotFound }: UseChatOption
   // 用 ref 存储回调，避免依赖变化导致无限循环
   const onErrorRef = useRef(onError);
   const onSessionNotFoundRef = useRef(onSessionNotFound);
+  const onSessionUpdatedRef = useRef(onSessionUpdated);
   onErrorRef.current = onError;
   onSessionNotFoundRef.current = onSessionNotFound;
+  onSessionUpdatedRef.current = onSessionUpdated;
 
   // 加载历史消息
   const loadMessages = useCallback(async () => {
@@ -134,6 +137,13 @@ export function useChat({ sessionId, onError, onSessionNotFound }: UseChatOption
             onErrorRef.current?.(new Error(message.payload?.message || 'Unknown error'));
             setState((prev) => ({ ...prev, isLoading: false, streamingContent: '' }));
             break;
+
+          case 'session_updated':
+            // 会话信息更新（如标题）
+            if (message.payload?.id && message.payload?.name) {
+              onSessionUpdatedRef.current?.(message.payload.id, message.payload.name);
+            }
+            break;
         }
       } catch {
         // 忽略解析错误

packages/web/src/App.tsx

@@ -21,6 +21,7 @@ export function App() {
   const [isInitializing, setIsInitializing] = useState(true);
   const [showFileBrowser, setShowFileBrowser] = useState(false);
   const [showConfig, setShowConfig] = useState(false);
+  const [sessionTitleUpdate, setSessionTitleUpdate] = useState<{ sessionId: string; name: string } | null>(null);
 
   // 初始化：加载或创建会话
   useEffect(() => {
@@ -64,6 +65,11 @@ export function App() {
     }
   }, []);
 
+  // 会话标题更新回调
+  const handleSessionUpdated = useCallback((sessionId: string, name: string) => {
+    setSessionTitleUpdate({ sessionId, name });
+  }, []);
+
   if (isInitializing) {
     return (
       <div className="h-screen flex items-center justify-center bg-gray-900">
@@ -82,6 +88,7 @@ export function App() {
         onSelectSession={handleSelectSession}
         onCreateSession={handleCreateSession}
         responsive
+        sessionTitleUpdate={sessionTitleUpdate}
       />
 
       {/* 主内容区域 */}
@@ -93,6 +100,7 @@ export function App() {
               key={currentSessionId}
               sessionId={currentSessionId}
               onSessionNotFound={handleSessionNotFound}
+              onSessionUpdated={handleSessionUpdated}
               responsive
               showFileBrowser={showFileBrowser}
               onToggleFileBrowser={() => setShowFileBrowser(!showFileBrowser)}

packages/web/src/pages/Chat.tsx

@@ -16,6 +16,7 @@ import {
 interface ChatPageProps {
   sessionId: string;
   onSessionNotFound?: () => void;
+  onSessionUpdated?: (sessionId: string, name: string) => void;
   responsive?: boolean;
   // 工具栏按钮
   showFileBrowser?: boolean;
@@ -26,6 +27,7 @@ interface ChatPageProps {
 export function ChatPage({
   sessionId,
   onSessionNotFound,
+  onSessionUpdated,
   responsive = false,
   showFileBrowser,
   onToggleFileBrowser,
@@ -44,6 +46,7 @@ export function ChatPage({
       console.error('Chat error:', error);
     },
     onSessionNotFound,
+    onSessionUpdated,
   });
 
   const messagesEndRef = useRef<HTMLDivElement>(null);