refactor(chat): remove frontend state saves

src/components/chat/chatStorage.test.ts

@@ -1,6 +1,9 @@
 import {
   createEmptyChatState,
-  saveActiveChatState,
+  deleteChatSession,
+  listChatSessions,
+  loadChatSessionById,
+  updateChatSessionTitle,
 } from "./chatStorage";
 
 const apiFetch = jest.fn();
@@ -9,7 +12,7 @@ jest.mock("@/lib/apiFetch", () => ({
   apiFetch: (...args: unknown[]) => apiFetch(...args),
 }));
 
-describe("chatStorage backend-only persistence", () => {
+describe("chatStorage backend session operations", () => {
   beforeEach(() => {
     apiFetch.mockReset();
   });
@@ -25,46 +28,106 @@ describe("chatStorage backend-only persistence", () => {
     expect(apiFetch).not.toHaveBeenCalled();
   });
 
-  it("creates a backend conversation when saving the first non-empty state", async () => {
+  it("lists backend sessions sorted by created time", async () => {
-    apiFetch.mockImplementation(async (url: string, init?: RequestInit) => {
+    apiFetch.mockResolvedValueOnce({
-      if (url.endsWith("/api/v1/agent/chat/session")) {
-        expect(init?.method).toBe("POST");
-        return {
       ok: true,
-          json: async () => ({ session_id: "chat-new-1" }),
+      json: async () => ({
-        } as Response;
+        sessions: [
-      }
-
-      if (url.endsWith("/api/v1/agent/chat/session/chat-new-1")) {
-        expect(init?.method).toBe("PUT");
-        expect(JSON.parse(String(init?.body))).toMatchObject({
-          title: "新对话",
-          is_title_manually_edited: false,
-        });
-        return {
-          ok: true,
-          json: async () => ({ id: "chat-new-1", session_id: "chat-new-1" }),
-        } as Response;
-      }
-
-      throw new Error(`Unexpected request ${url}`);
-    });
-
-    const savedSessionId = await saveActiveChatState(
           {
-        title: "新对话",
+            id: "session-old",
-        isTitleManuallyEdited: false,
+            title: "旧会话",
-        messages: [
+            created_at: "2026-01-01T00:00:00.000Z",
+            updated_at: "2026-01-02T00:00:00.000Z",
+          },
           {
-            id: "message-2",
+            id: "session-new",
-            role: "user",
+            title: "新会话",
-            content: "第一条消息",
+            created_at: "2026-01-03T00:00:00.000Z",
+            updated_at: "2026-01-03T00:00:00.000Z",
+            is_streaming: true,
+            run_status: "running",
           },
         ],
-        sessionId: undefined,
+      }),
-      },
+    });
-    );
 
-    expect(savedSessionId).toBe("chat-new-1");
+    await expect(listChatSessions()).resolves.toEqual([
+      expect.objectContaining({
+        id: "session-new",
+        title: "新会话",
+        isStreaming: true,
+        runStatus: "running",
+      }),
+      expect.objectContaining({
+        id: "session-old",
+        title: "旧会话",
+      }),
+    ]);
+    expect(apiFetch.mock.calls[0][1]).toMatchObject({ method: "GET" });
+  });
+
+  it("loads a backend session state", async () => {
+    apiFetch.mockResolvedValueOnce({
+      ok: true,
+      json: async () => ({
+        id: "session-1",
+        title: "管网分析",
+        is_title_manually_edited: true,
+        messages: [{ id: "message-1", role: "user", content: "查压力" }],
+        is_streaming: false,
+      }),
+    });
+
+    await expect(loadChatSessionById("session-1")).resolves.toMatchObject({
+      title: "管网分析",
+      isTitleManuallyEdited: true,
+      sessionId: "session-1",
+      messages: [{ id: "message-1", role: "user", content: "查压力" }],
+    });
+    expect(String(apiFetch.mock.calls[0][0])).toContain("/session/session-1");
+    expect(apiFetch.mock.calls[0][1]).toMatchObject({ method: "GET" });
+  });
+
+  it("updates a backend session title through the title endpoint", async () => {
+    apiFetch.mockResolvedValueOnce({
+      ok: true,
+      text: async () => "",
+    });
+
+    await updateChatSessionTitle("session-1", " 新标题 ", {
+      isTitleManuallyEdited: true,
+    });
+
+    expect(String(apiFetch.mock.calls[0][0])).toContain("/session/session-1/title");
+    expect(apiFetch.mock.calls[0][1]).toMatchObject({ method: "PATCH" });
+    expect(JSON.parse(String(apiFetch.mock.calls[0][1]?.body))).toEqual({
+      title: "新标题",
+      is_title_manually_edited: true,
+    });
+  });
+
+  it("deletes a backend session and returns the next active session id", async () => {
+    apiFetch
+      .mockResolvedValueOnce({
+        ok: true,
+        text: async () => "",
+      })
+      .mockResolvedValueOnce({
+        ok: true,
+        json: async () => ({
+          sessions: [
+            {
+              id: "session-next",
+              title: "下一会话",
+              created_at: "2026-01-01T00:00:00.000Z",
+              updated_at: "2026-01-01T00:00:00.000Z",
+            },
+          ],
+        }),
+      });
+
+    await expect(deleteChatSession("session-1")).resolves.toBe("session-next");
+    expect(apiFetch.mock.calls[0][1]).toMatchObject({ method: "DELETE" });
+    expect(apiFetch.mock.calls[1][1]).toMatchObject({ method: "GET" });
   });
 });

src/components/chat/chatStorage.ts

@@ -27,13 +27,6 @@ export const createEmptyChatState = (): LoadedChatState => ({
 const sanitizeMessages = (messages: Message[] | undefined) =>
   Array.isArray(messages) ? cloneMessages(messages) : [];
 
-const hasChatContent = (state: {
-  messages: Message[];
-  sessionId?: string;
-}) =>
-  state.messages.length > 0 ||
-  Boolean(state.sessionId);
-
 const compareSessionsByAnchorTime = (
   left: Pick<ChatSessionSummary, "id" | "createdAt" | "updatedAt">,
   right: Pick<ChatSessionSummary, "id" | "createdAt" | "updatedAt">,
@@ -113,64 +106,6 @@ const fetchBackendChatSession = async (sessionId: string): Promise<LoadedChatSta
   };
 };
 
-const createBackendChatSession = async (payload?: {
-  sessionId?: string;
-  parentSessionId?: string;
-}) => {
-  const response = await apiFetch(`${config.AGENT_URL}/api/v1/agent/chat/session`, {
-    method: "POST",
-    headers: {
-      "Content-Type": "application/json",
-    },
-    body: JSON.stringify({
-      session_id: payload?.sessionId,
-      parent_session_id: payload?.parentSessionId,
-    }),
-    projectHeaderMode: "include",
-    userHeaderMode: "include",
-    skipAuthRedirect: true,
-  });
-  if (!response.ok) {
-    throw new Error(await response.text());
-  }
-  const body = (await response.json()) as {
-    session_id?: string;
-  };
-  const sessionId = body.session_id?.trim();
-  if (!sessionId) {
-    throw new Error("backend did not return session_id");
-  }
-  return sessionId;
-};
-
-const saveBackendChatState = async (
-  sessionId: string,
-  state: LoadedChatState,
-): Promise<string> => {
-  const response = await apiFetch(
-    `${config.AGENT_URL}/api/v1/agent/chat/session/${encodeURIComponent(sessionId)}`,
-    {
-      method: "PUT",
-      headers: {
-        "Content-Type": "application/json",
-      },
-      body: JSON.stringify({
-        title: normalizeTitle(state.title),
-        is_title_manually_edited: state.isTitleManuallyEdited ?? false,
-        messages: sanitizeMessages(state.messages),
-      }),
-      projectHeaderMode: "include",
-      userHeaderMode: "include",
-      skipAuthRedirect: true,
-    },
-  );
-  if (!response.ok) {
-    throw new Error(await response.text());
-  }
-  const payload = (await response.json()) as { id?: string; session_id?: string };
-  return payload.id ?? payload.session_id ?? sessionId;
-};
-
 const updateBackendChatSessionTitle = async (
   sessionId: string,
   title: string,
@@ -212,27 +147,6 @@ const deleteBackendChatSession = async (sessionId: string) => {
   }
 };
 
-export const saveActiveChatState = async (
-  state: LoadedChatState,
-): Promise<string | undefined> => {
-  if (typeof window === "undefined") return state.sessionId;
-
-  if (!hasChatContent(state)) {
-    return undefined;
-  }
-
-  let backendSessionId = state.sessionId;
-  if (!backendSessionId) {
-    backendSessionId = await createBackendChatSession();
-  }
-
-  const savedSessionId = await saveBackendChatState(backendSessionId, {
-    ...state,
-    sessionId: backendSessionId,
-  });
-  return savedSessionId;
-};
-
 export const listChatSessions = async (): Promise<ChatSessionSummary[]> => {
   if (typeof window === "undefined") return [];
   return await fetchBackendChatSessions();

src/components/chat/hooks/agentChatSessionState.ts

@@ -7,19 +7,10 @@ import type {
 import type {
   AgentPermissionRequest,
   ChatProgress,
-  LoadedChatState,
   Message,
 } from "../GlobalChatbox.types";
 import { createId } from "../GlobalChatbox.utils";
 
-export const createPersistedStateKey = (state: LoadedChatState) =>
-  JSON.stringify({
-    title: state.title ?? null,
-    isTitleManuallyEdited: state.isTitleManuallyEdited ?? false,
-    sessionId: state.sessionId ?? null,
-    messages: state.messages,
-  });
-
 export const upsertProgress = (
   progress: ChatProgress[] | undefined,
   event: StreamEvent & { type: "progress" },

src/components/chat/hooks/useAgentChatSession.actions.test.tsx

@@ -24,7 +24,6 @@ jest.mock("@/lib/chatStream", () => ({
 
 const listChatSessions = jest.fn();
 const deleteChatSession = jest.fn();
-const saveActiveChatState = jest.fn();
 const updateChatSessionTitle = jest.fn();
 
 jest.mock("../chatStorage", () => ({
@@ -42,7 +41,6 @@ jest.mock("../chatStorage", () => ({
     messages: [],
     sessionId: "session-loaded",
   })),
-  saveActiveChatState: (...args: unknown[]) => saveActiveChatState(...args),
   updateChatSessionTitle: (...args: unknown[]) => updateChatSessionTitle(...args),
 }));
 
@@ -50,7 +48,6 @@ describe("useAgentChatSession", () => {
   beforeEach(() => {
     listChatSessions.mockReset();
     deleteChatSession.mockReset();
-    saveActiveChatState.mockReset();
     updateChatSessionTitle.mockReset();
     jest.mocked(abortAgentChat).mockReset();
     jest.mocked(forkAgentChat).mockReset();
@@ -65,7 +62,6 @@ describe("useAgentChatSession", () => {
     jest.mocked(resumeAgentChatStream).mockImplementation(async () => undefined);
     jest.mocked(streamAgentChat).mockImplementation(async () => undefined);
     deleteChatSession.mockImplementation(async () => undefined);
-    saveActiveChatState.mockImplementation(async (state) => state.sessionId);
     updateChatSessionTitle.mockImplementation(async () => undefined);
   });
 

src/components/chat/hooks/useAgentChatSession.lifecycle.test.tsx

@@ -24,7 +24,6 @@ jest.mock("@/lib/chatStream", () => ({
 
 const listChatSessions = jest.fn();
 const deleteChatSession = jest.fn();
-const saveActiveChatState = jest.fn();
 const updateChatSessionTitle = jest.fn();
 
 jest.mock("../chatStorage", () => ({
@@ -42,7 +41,6 @@ jest.mock("../chatStorage", () => ({
     messages: [],
     sessionId: "session-loaded",
   })),
-  saveActiveChatState: (...args: unknown[]) => saveActiveChatState(...args),
   updateChatSessionTitle: (...args: unknown[]) => updateChatSessionTitle(...args),
 }));
 
@@ -50,7 +48,6 @@ describe("useAgentChatSession", () => {
   beforeEach(() => {
     listChatSessions.mockReset();
     deleteChatSession.mockReset();
-    saveActiveChatState.mockReset();
     updateChatSessionTitle.mockReset();
     jest.mocked(abortAgentChat).mockReset();
     jest.mocked(forkAgentChat).mockReset();
@@ -65,7 +62,6 @@ describe("useAgentChatSession", () => {
     jest.mocked(resumeAgentChatStream).mockImplementation(async () => undefined);
     jest.mocked(streamAgentChat).mockImplementation(async () => undefined);
     deleteChatSession.mockImplementation(async () => undefined);
-    saveActiveChatState.mockImplementation(async (state) => state.sessionId);
     updateChatSessionTitle.mockImplementation(async () => undefined);
   });
 
@@ -190,7 +186,7 @@ describe("useAgentChatSession lifecycle and resume", () => {
     );
   });
 
-  it("persists a new conversation only after the stream is done", async () => {
+  it("does not autosave full messages after the stream is done", async () => {
     listChatSessions.mockResolvedValue([]);
     let emitStreamEvent: ((event: StreamEvent) => void) | undefined;
     jest.mocked(streamAgentChat).mockImplementationOnce(async ({ onEvent }) => {
@@ -220,8 +216,6 @@ describe("useAgentChatSession lifecycle and resume", () => {
         jest.advanceTimersByTime(200);
       });
 
-      expect(saveActiveChatState).not.toHaveBeenCalled();
-
       act(() => {
         emitStreamEvent?.({
           type: "token",
@@ -234,8 +228,6 @@ describe("useAgentChatSession lifecycle and resume", () => {
         jest.advanceTimersByTime(200);
       });
 
-      expect(saveActiveChatState).not.toHaveBeenCalled();
-
       act(() => {
         emitStreamEvent?.({
           type: "done",
@@ -247,14 +239,11 @@ describe("useAgentChatSession lifecycle and resume", () => {
         jest.advanceTimersByTime(200);
       });
 
-      await waitFor(() => expect(saveActiveChatState).toHaveBeenCalledTimes(1));
+      expect(result.current.messages).toEqual([
-      expect(saveActiveChatState.mock.calls[0][0]).toMatchObject({
-        sessionId: "chat-stream-1",
-        messages: [
         expect.objectContaining({ role: "user", content: "第一条消息" }),
         expect.objectContaining({ role: "assistant", content: "收到" }),
-        ],
+      ]);
-      });
+      expect(result.current.activeSessionId).toBe("chat-stream-1");
     } finally {
       jest.useRealTimers();
     }

src/components/chat/hooks/useAgentChatSession.ts

@@ -4,10 +4,10 @@ import { useCallback, useEffect, useRef, useState } from "react";
 
 import { abortAgentChat, forkAgentChat, rejectAgentQuestion, replyAgentPermission, replyAgentQuestion, resumeAgentChatStream, streamAgentChat } from "@/lib/chatStream";
 import type { PermissionReply, StreamEvent } from "@/lib/chatStream";
-import type { AgentArtifact, ChatSessionSummary, LoadedChatState, Message } from "../GlobalChatbox.types";
+import type { AgentArtifact, ChatSessionSummary, Message } from "../GlobalChatbox.types";
 import { cloneMessages } from "../GlobalChatbox.utils";
-import { createEmptyChatState, deleteChatSession, listChatSessions, loadChatSessionById, saveActiveChatState, updateChatSessionTitle } from "../chatStorage";
+import { createEmptyChatState, deleteChatSession, listChatSessions, loadChatSessionById, updateChatSessionTitle } from "../chatStorage";
-import { applyQuestionResponse, cancelRunningTodos, completeRunningProgress, createAssistantMessage, createPersistedStateKey, createTodoUpdateFromEvent, createUserMessage, dedupeQuestionsAcrossMessages, finalizeAssistantMessageAfterAbort, normalizeSessionTodos, toPermissionStatus, upsertPermission, upsertProgress, upsertQuestionAcrossMessages } from "./agentChatSessionState";
+import { applyQuestionResponse, cancelRunningTodos, completeRunningProgress, createAssistantMessage, createTodoUpdateFromEvent, createUserMessage, dedupeQuestionsAcrossMessages, finalizeAssistantMessageAfterAbort, normalizeSessionTodos, toPermissionStatus, upsertPermission, upsertProgress, upsertQuestionAcrossMessages } from "./agentChatSessionState";
 import type { PromptRunOptions, UseAgentChatSessionOptions } from "./useAgentChatSession.types";
 
 export const useAgentChatSession = ({
@@ -17,7 +17,6 @@ export const useAgentChatSession = ({
   getModel,
   getApprovalMode,
 }: UseAgentChatSessionOptions) => {
-  const hydrationCompletedRef = useRef(false);
   const hydrationNonceRef = useRef(0);
 
   const [messages, setMessages] = useState<Message[]>([]);
@@ -35,14 +34,6 @@ export const useAgentChatSession = ({
   const isSessionTitleManuallyEditedRef = useRef(false);
   const cancelPromiseRef = useRef<Promise<void> | null>(null);
   const titleUpdateNonceRef = useRef(0);
-  const lastPersistedStateKeyRef = useRef(
-    createPersistedStateKey({
-      sessionId: undefined,
-      title: undefined,
-      isTitleManuallyEdited: false,
-      messages: [],
-    }),
-  );
 
   useEffect(() => {
     sessionIdRef.current = sessionId;
@@ -62,17 +53,9 @@ export const useAgentChatSession = ({
 
     const hydrate = async () => {
       setIsHydrating(true);
-      hydrationCompletedRef.current = false;
 
       if (!projectId) {
         sessionIdRef.current = undefined;
-        lastPersistedStateKeyRef.current = createPersistedStateKey({
-          title: undefined,
-          isTitleManuallyEdited: false,
-          messages: [],
-          sessionId: undefined,
-        });
-        hydrationCompletedRef.current = true;
         hydrationNonceRef.current += 1;
         titleUpdateNonceRef.current += 1;
         setMessages([]);
@@ -93,8 +76,6 @@ export const useAgentChatSession = ({
         if (cancelled) return;
 
         sessionIdRef.current = loadedState.sessionId;
-        lastPersistedStateKeyRef.current = createPersistedStateKey(loadedState);
-        hydrationCompletedRef.current = true;
         hydrationNonceRef.current += 1;
         titleUpdateNonceRef.current += 1;
 
@@ -127,51 +108,6 @@ export const useAgentChatSession = ({
     };
   }, [projectId]);
 
-  useEffect(() => {
-    if (!projectId || isHydrating || !hydrationCompletedRef.current) return;
-
-    const currentHydrationNonce = hydrationNonceRef.current;
-    const persistTimer = window.setTimeout(() => {
-      if (isStreaming) {
-        return;
-      }
-
-      const state: LoadedChatState = {
-        title: sessionTitle,
-        isTitleManuallyEdited: isSessionTitleManuallyEdited,
-        messages,
-        sessionId,
-      };
-
-      const currentStateKey = createPersistedStateKey(state);
-      if (currentStateKey === lastPersistedStateKeyRef.current) {
-        return;
-      }
-
-      void saveActiveChatState(state)
-        .then((sessionId) => {
-          if (hydrationNonceRef.current !== currentHydrationNonce) return;
-          sessionIdRef.current = sessionId;
-          lastPersistedStateKeyRef.current = createPersistedStateKey({
-            ...state,
-            sessionId,
-          });
-          return listChatSessions();
-        })
-        .then((sessions) => {
-          if (!sessions || hydrationNonceRef.current !== currentHydrationNonce) return;
-          setChatSessions(sessions);
-        })
-        .catch((error) => {
-          console.error("[GlobalChatbox] Failed to persist chat state:", error);
-        });
-    }, 150);
-
-    return () => {
-      window.clearTimeout(persistTimer);
-    };
-  }, [isHydrating, isSessionTitleManuallyEdited, isStreaming, messages, projectId, sessionId, sessionTitle]);
-
   const appendArtifact = useCallback((messageId: string, artifact: AgentArtifact) => {
     setMessages((prev) =>
       prev.map((message) =>
@@ -226,12 +162,6 @@ export const useAgentChatSession = ({
           const targetSessionId = event.sessionId || currentSessionId;
           if (targetSessionId === currentSessionId) {
             setSessionTitle(nextTitle);
-            lastPersistedStateKeyRef.current = createPersistedStateKey({
-              sessionId: targetSessionId,
-              title: nextTitle,
-              isTitleManuallyEdited: false,
-              messages: messagesRef.current,
-            });
           }
           if (targetSessionId) {
             const currentNonce = ++titleUpdateNonceRef.current;
@@ -743,12 +673,6 @@ export const useAgentChatSession = ({
     hydrationNonceRef.current += 1;
     titleUpdateNonceRef.current += 1;
     sessionIdRef.current = undefined;
-    lastPersistedStateKeyRef.current = createPersistedStateKey({
-      title: "新对话",
-      isTitleManuallyEdited: false,
-      messages: [],
-      sessionId: undefined,
-    });
     setMessages([]);
     setSessionTitle("新对话");
     setIsSessionTitleManuallyEdited(false);
@@ -777,7 +701,6 @@ export const useAgentChatSession = ({
         hydrationNonceRef.current += 1;
         titleUpdateNonceRef.current += 1;
         sessionIdRef.current = nextState.sessionId;
-        lastPersistedStateKeyRef.current = createPersistedStateKey(nextState);
         setMessages(nextState.messages);
         setSessionTitle(nextState.title);
         setIsSessionTitleManuallyEdited(nextState.isTitleManuallyEdited ?? false);
@@ -821,12 +744,6 @@ export const useAgentChatSession = ({
           hydrationNonceRef.current += 1;
           titleUpdateNonceRef.current += 1;
           sessionIdRef.current = undefined;
-          lastPersistedStateKeyRef.current = createPersistedStateKey({
-            title: undefined,
-            isTitleManuallyEdited: false,
-            messages: [],
-            sessionId: undefined,
-          });
           setMessages([]);
           setSessionTitle(undefined);
           setIsSessionTitleManuallyEdited(false);
@@ -842,7 +759,6 @@ export const useAgentChatSession = ({
         hydrationNonceRef.current += 1;
         titleUpdateNonceRef.current += 1;
         sessionIdRef.current = nextState.sessionId;
-        lastPersistedStateKeyRef.current = createPersistedStateKey(nextState);
         setMessages(nextState.messages);
         setSessionTitle(nextState.title);
         setIsSessionTitleManuallyEdited(nextState.isTitleManuallyEdited ?? false);
@@ -884,18 +800,12 @@ export const useAgentChatSession = ({
         if (sessionIdRef.current === targetSessionId) {
           setSessionTitle(normalizedTitle);
           setIsSessionTitleManuallyEdited(true);
-          lastPersistedStateKeyRef.current = createPersistedStateKey({
-            sessionId: targetSessionId,
-            title: normalizedTitle,
-            isTitleManuallyEdited: true,
-            messages,
-          });
         }
       } catch (error) {
         console.error("[GlobalChatbox] Failed to rename chat session:", error);
       }
     },
-    [isHydrating, messages],
+    [isHydrating],
   );
 
   const createBranch = useCallback(
@@ -920,12 +830,6 @@ export const useAgentChatSession = ({
       const forkTitle = sessionTitle ? `${sessionTitle} 副本` : "新对话副本";
       setSessionTitle(forkTitle);
       try {
-        await saveActiveChatState({
-          title: forkTitle,
-          isTitleManuallyEdited: false,
-          messages: copiedMessages,
-          sessionId: forkedSessionId,
-        });
         setChatSessions(await listChatSessions());
       } catch (error) {
         console.error("[GlobalChatbox] Failed to refresh chat sessions after fork:", error);