fix(web): preserve manual session titles

CHANGELOG.md

@@ -11,6 +11,8 @@ Only write entries that are worth mentioning to users.
 
 ## Unreleased
 
+- Web: Fix session rename, archive, and title generation being incorrectly rejected when the session is busy — these state-only edits now bypass the busy check and safely merge concurrent worker changes via on-disk state reloads. Title generation also preserves a title finalized by another request while the LLM call was in flight
+- Web: Show toast error notifications in the web UI for session rename, archive, unarchive, delete, and title generation failures
 - Kosong: Fix stale API key after OAuth token refresh in Kimi provider — `on_retryable_error` now reads the current `api_key` from the live client instead of the cached `_api_key`, so that OAuth token refreshes applied via `client.api_key` are preserved when the client is rebuilt after a retryable error
 - Core: Approval requests no longer auto-timeout after 5 minutes, which previously surfaced as `Rejected by user`; active foreground and subagent approvals now wait indefinitely for user response
 - Core: Fix yolo mode reminder being lost after context compaction — the non-interactive-mode guidance ("don't call AskUserQuestion, plan-mode toggles are auto-approved") is now re-injected on the first LLM step after each compaction while yolo remains active, instead of being silently dropped when the original reminder is folded into the compaction summary

docs/en/release-notes/changelog.md

@@ -4,6 +4,8 @@ This page documents the changes in each Kimi Code CLI release.
 
 ## Unreleased
 
+- Web: Fix session rename, archive, and title generation being incorrectly rejected when the session is busy — these state-only edits now bypass the busy check and safely merge concurrent worker changes via on-disk state reloads. Title generation also preserves a title finalized by another request while the LLM call was in flight
+- Web: Show toast error notifications in the web UI for session rename, archive, unarchive, delete, and title generation failures
 - Kosong: Fix stale API key after OAuth token refresh in Kimi provider — `on_retryable_error` now reads the current `api_key` from the live client instead of the cached `_api_key`, so that OAuth token refreshes applied via `client.api_key` are preserved when the client is rebuilt after a retryable error
 - Core: Approval requests no longer auto-timeout after 5 minutes, which previously surfaced as `Rejected by user`; active foreground and subagent approvals now wait indefinitely for user response
 - Core: Fix yolo mode reminder being lost after context compaction — the non-interactive-mode guidance ("don't call AskUserQuestion, plan-mode toggles are auto-approved") is now re-injected on the first LLM step after each compaction while yolo remains active, instead of being silently dropped when the original reminder is folded into the compaction summary

docs/zh/release-notes/changelog.md

@@ -4,6 +4,8 @@
 
 ## 未发布
 
+- Web：修复会话处于忙碌状态时重命名、归档和生成标题被错误拒绝的问题——这些仅修改状态的操作现在会绕过忙碌检查，并通过从磁盘重新加载状态来安全合并并发 worker 的变更。标题生成现在也会保留在 LLM 调用过程中被其它请求最终确定的标题
+- Web：在 Web UI 中为会话重命名、归档、取消归档、删除和标题生成失败添加 toast 错误提示
 - Kosong：修复 Kimi 供应商在 OAuth 令牌刷新后仍使用过期的 API 密钥的问题——`on_retryable_error` 现在从当前 client 读取 `api_key`，而不是缓存的 `_api_key`，因此在可重试错误后重建 client 时会保留通过 `client.api_key` 应用的 OAuth 令牌刷新
 - Core：修复审批请求 5 分钟自动超时并被误报为 `Rejected by user` 的问题；现在活跃的前台和子 Agent 审批请求都会无限等待用户响应
 - Core：修复上下文压缩后 yolo 模式提示词丢失的问题——当 yolo 模式处于激活状态时，非交互模式下的指导提示（不要调用 AskUserQuestion、计划模式切换自动批准等）现在会在每次上下文压缩后的第一个 LLM 步骤重新注入，而不是在原始提示被折叠进压缩摘要后静默消失

src/kimi_cli/web/api/sessions.py

@@ -106,18 +106,30 @@ def get_runner_ws(ws: WebSocket) -> KimiCLIRunner:
     return ws.app.state.runner
 
 
-def get_editable_session(
-    session_id: UUID,
-    runner: KimiCLIRunner,
-) -> JointSession:
-    """Get a session and verify it's not busy."""
+def get_session_or_404(session_id: UUID) -> JointSession:
+    """Load a session by id, raising 404 if it doesn't exist."""
     session = load_session_by_id(session_id)
     if session is None:
         raise HTTPException(
             status_code=status.HTTP_404_NOT_FOUND,
             detail="Session not found",
         )
-    # Check if session is busy
+    return session
+
+
+def get_editable_session(
+    session_id: UUID,
+    runner: KimiCLIRunner,
+) -> JointSession:
+    """Get a session and verify it's not busy.
+
+    Use for operations that cannot run concurrently with a live worker
+    (delete, fork, upload). For state-only edits (rename, archive,
+    generate-title) the worker merges externally-mutable fields back
+    via ``Session.save_state``; those endpoints can use
+    :func:`get_session_or_404` instead.
+    """
+    session = get_session_or_404(session_id)
     session_process = runner.get_session(session_id)
     if session_process and session_process.is_busy:
         raise HTTPException(
@@ -586,12 +598,16 @@ async def delete_session(session_id: UUID, runner: KimiCLIRunner = Depends(get_r
 async def update_session(
     session_id: UUID,
     request: UpdateSessionRequest,
-    runner: KimiCLIRunner = Depends(get_runner),
 ) -> Session:
-    """Update a session (e.g., rename title or archive/unarchive)."""
+    """Update a session (e.g., rename title or archive/unarchive).
+
+    Safe to invoke while a worker is running: only externally-mutable
+    fields are touched, and ``Session.save_state`` reloads them from
+    disk before each worker write.
+    """
     from kimi_cli.session_state import load_session_state, save_session_state
 
-    session = get_editable_session(session_id, runner)
+    session = get_session_or_404(session_id)
     session_dir = session.kimi_cli_session.dir
     state = load_session_state(session_dir)
 
@@ -749,14 +765,16 @@ async def fork_session_endpoint(
 async def generate_session_title(
     session_id: UUID,
     request: GenerateTitleRequest | None = None,
-    runner: KimiCLIRunner = Depends(get_runner),
 ) -> GenerateTitleResponse:
     """Generate a concise session title using AI based on the first conversation turn.
 
     If request body is empty or parameters are missing, the backend will
     automatically read the first turn from wire.jsonl.
+
+    Safe to invoke while a worker is running: the final write reloads
+    state from disk to merge concurrent worker changes.
     """
-    session = get_editable_session(session_id, runner)
+    session = get_session_or_404(session_id)
     session_dir = session.kimi_cli_session.dir
 
     from kimi_cli.session_state import load_session_state, save_session_state
@@ -789,6 +807,11 @@ async def generate_session_title(
     # If AI generation failed too many times, use fallback and mark as generated
     if state.title_generate_attempts >= 3:
         fresh = load_session_state(session_dir)
+        # Respect a title finalized by another request/user action while we
+        # were preparing a fallback.
+        if fresh.title_generated:
+            invalidate_sessions_cache()
+            return GenerateTitleResponse(title=fresh.custom_title or "Untitled")
         fresh.custom_title = fallback_title
         fresh.title_generated = True
         save_session_state(fresh, session_dir)
@@ -856,6 +879,11 @@ async def generate_session_title(
     # Read-modify-write: reload fresh state to avoid overwriting
     # worker changes made during the LLM call
     fresh = load_session_state(session_dir)
+    # Another request or manual rename may have finalized the title while the
+    # LLM call was in flight. Preserve that newer title instead of clobbering it.
+    if fresh.title_generated:
+        invalidate_sessions_cache()
+        return GenerateTitleResponse(title=fresh.custom_title or "Untitled")
     fresh.custom_title = title
     if ai_generated:
         fresh.title_generated = True

tests/web/test_sessions_api.py

@@ -0,0 +1,104 @@
+from __future__ import annotations
+
+from pathlib import Path
+from types import SimpleNamespace
+from uuid import UUID
+
+import pytest
+from kaos.path import KaosPath
+
+from kimi_cli.session import Session
+from kimi_cli.session_state import load_session_state, save_session_state
+from kimi_cli.web.api import sessions as sessions_api
+from kimi_cli.web.models import GenerateTitleRequest
+
+
+@pytest.fixture
+def isolated_share_dir(monkeypatch, tmp_path: Path) -> Path:
+    share_dir = tmp_path / "share"
+    share_dir.mkdir()
+
+    def _get_share_dir() -> Path:
+        share_dir.mkdir(parents=True, exist_ok=True)
+        return share_dir
+
+    monkeypatch.setattr("kimi_cli.share.get_share_dir", _get_share_dir)
+    monkeypatch.setattr("kimi_cli.metadata.get_share_dir", _get_share_dir)
+    return share_dir
+
+
+@pytest.fixture
+def work_dir(tmp_path: Path) -> KaosPath:
+    path = tmp_path / "work"
+    path.mkdir()
+    return KaosPath.unsafe_from_local_path(path)
+
+
+class _FakeOAuthManager:
+    def __init__(self, _config: object) -> None:
+        pass
+
+    async def ensure_fresh(self) -> None:
+        return None
+
+
+class _FakeLLM:
+    chat_provider = object()
+
+
+class _FakeMessage:
+    def __init__(self, text: str) -> None:
+        self._text = text
+
+    def extract_text(self) -> str:
+        return self._text
+
+
+class _FakeResult:
+    def __init__(self, text: str) -> None:
+        self.message = _FakeMessage(text)
+
+
+@pytest.mark.anyio
+async def test_generate_title_preserves_concurrent_manual_title(
+    isolated_share_dir: Path,
+    work_dir: KaosPath,
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    session = await Session.create(work_dir)
+
+    config = SimpleNamespace(
+        default_model="test-model",
+        models={"test-model": SimpleNamespace(provider="test-provider")},
+        providers={"test-provider": object()},
+    )
+
+    monkeypatch.setattr("kimi_cli.config.load_config", lambda: config)
+    monkeypatch.setattr(
+        "kimi_cli.llm.create_llm",
+        lambda provider_config, model_config, oauth=None: _FakeLLM(),
+    )
+    monkeypatch.setattr("kimi_cli.auth.oauth.OAuthManager", _FakeOAuthManager)
+
+    async def fake_generate(*, chat_provider, system_prompt, tools, history):
+        state = load_session_state(session.dir)
+        state.custom_title = "Manual Title"
+        state.title_generated = True
+        save_session_state(state, session.dir)
+        return _FakeResult("AI Title")
+
+    monkeypatch.setattr("kosong.generate", fake_generate)
+
+    response = await sessions_api.generate_session_title(
+        UUID(session.id),
+        GenerateTitleRequest(
+            user_message="debug the flaky web session rename issue",
+            assistant_response="I'll inspect the session state writes.",
+        ),
+    )
+
+    state = load_session_state(session.dir)
+    assert response.title == "Manual Title"
+    assert state.custom_title == "Manual Title"
+    assert state.title_generated is True
+    assert state.title_generate_attempts == 0

web/src/hooks/useSessions.ts

@@ -1,4 +1,5 @@
 import { useState, useCallback, useEffect, useRef } from "react";
+import { toast } from "sonner";
 import type {
   Session,
   UploadSessionFileResponse,
@@ -512,6 +513,7 @@ export function useSessions(): UseSessionsReturn {
         const message =
           err instanceof Error ? err.message : "Failed to delete session";
         setError(message);
+        toast.error(message);
         return false;
       } finally {
         setIsLoading(false);
@@ -703,7 +705,10 @@ export function useSessions(): UseSessionsReturn {
         await refreshSession(sessionId);
         return true;
       } catch (err) {
+        const message =
+          err instanceof Error ? err.message : "Failed to rename session";
         console.error("Failed to rename session:", err);
+        toast.error(message);
         return false;
       }
     },
@@ -740,7 +745,10 @@ export function useSessions(): UseSessionsReturn {
         await refreshSession(sessionId);
         return result.title;
       } catch (err) {
+        const message =
+          err instanceof Error ? err.message : "Failed to generate title";
         console.error("Failed to generate title:", err);
+        toast.error(message);
         return null;
       }
     },
@@ -790,7 +798,10 @@ export function useSessions(): UseSessionsReturn {
 
         return true;
       } catch (err) {
+        const message =
+          err instanceof Error ? err.message : "Failed to archive session";
         console.error("Failed to archive session:", err);
+        toast.error(message);
         return false;
       }
     },
@@ -831,7 +842,10 @@ export function useSessions(): UseSessionsReturn {
 
         return true;
       } catch (err) {
+        const message =
+          err instanceof Error ? err.message : "Failed to unarchive session";
         console.error("Failed to unarchive session:", err);
+        toast.error(message);
         return false;
       }
     },