diff --git a/AGENTS.md b/AGENTS.md
index 627638aa..ac31ad3b 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -63,6 +63,7 @@ app/api/
   models-config/discover/route.ts POST fetch a configured provider's upstream model list
   models-config/test/route.ts     POST test a configured model/provider
   plugins/route.ts                GET/POST package plugin management
+  project-directories/route.ts    GET/POST/DELETE persisted sidebar directories
   skills/route.ts                 GET/PATCH loaded skills and disable-model-invocation
   skills/install/route.ts         POST install skills through npx skills add
   skills/search/route.ts          GET/POST skills.sh search
@@ -76,6 +77,7 @@ lib/
   markdown.ts          shared markdown helpers
   npx.ts               npx runner used by skill install
   pi-types.ts          local structural types for pi SDK objects
+  project-directories.ts persisted directory list in ~/.pi/agent/pi-web-projects.json
   rpc-manager.ts      AgentSessionWrapper + registry + startRpcSession
   session-reader.ts   SessionManager wrappers + path cache + buildSessionContext adapter
   tool-presets.ts     PRESET_NONE/DEFAULT/FULL + getPresetFromTools()
@@ -182,6 +184,13 @@ Newer pi emits `compaction_start` / `compaction_end`; older versions emitted `au
 - `hooks/useAudio.ts` stores the toggle in `localStorage` as `pi-sound-enabled` and reuses one `AudioContext`.
 - Browser autoplay policy means sound must be unlocked from a user gesture; `ChatInput` calls the unlock hook from interactive controls, and `ChatWindow` plays the tone from `onAgentEnd`.
 
+### PWA 版本与 Service Worker 更新策略
+- 生产环境必须使用每次构建唯一的版本标识注册 `/sw.js?v=<build-version>`，静态缓存名称也必须包含同一个版本；不能只使用长期不变的 `package.json` 版本，否则代码变化后浏览器可能继续命中旧 chunk。
+- 新 Service Worker 安装完成后保持 `waiting`，由界面提示“发现新版本”；用户确认后发送 `SKIP_WAITING`，并在 `controllerchange` 后刷新页面。不要在 `install` 阶段无条件调用 `skipWaiting()`。
+- 激活新 Service Worker 时只清理 `pi-web-` 前缀下的旧版本缓存，不得清理其它站点数据或认证信息。`/sw.js`、页面导航和 API 请求必须绕过静态资源缓存。
+- 开发环境不注册 Service Worker，并在 Next 客户端代码加载前注销同源旧注册、删除 `pi-web-` 缓存；清理完成后若页面仍被旧 worker 控制，只自动重载一次，避免刷新循环。
+- 重启 8081 的 Node/Next.js 进程不会注销浏览器中的 Service Worker。已有标签页或独立 PWA 窗口可能继续由旧 worker 控制，必须让页面重新加载并执行清理逻辑；必要时关闭该同源的全部页面后重新打开。
+
 ### Exported session HTML
 - `/api/sessions/[id]/export` delegates to pi's export helper, then patches recursive tree helpers in the generated HTML to iterative versions so very deep linear sessions do not overflow the browser call stack.
 
diff --git a/README.md b/README.md
index 0f666c08..a6e1f46f 100644
--- a/README.md
+++ b/README.md
@@ -113,7 +113,7 @@ Avoid running `next build` / `npm run build` during local development. It writes
 app/
   api/
     agent/          # creates/drives AgentSession and exposes SSE events
-    auth/           # OAuth and API key management
+    auth/           # password sessions, OAuth, and API key management
     cwd/browse/     # browsable server directory listing
     cwd/validate/   # custom working directory validation
     default-cwd/    # pi default working directory lookup
diff --git a/README.zh-CN.md b/README.zh-CN.md
index ae082007..fc466dde 100644
--- a/README.zh-CN.md
+++ b/README.zh-CN.md
@@ -109,7 +109,7 @@ npm run lint
 app/
   api/
     agent/          # 创建/驱动 AgentSession，提供 SSE 事件流
-    auth/           # OAuth 和 API key 管理
+    auth/           # 密码会话、OAuth 和 API key 管理
     cwd/browse/     # 服务端目录浏览
     cwd/validate/   # 自定义工作目录校验
     default-cwd/    # 获取 pi 默认工作目录
diff --git a/app/api/project-directories/route.ts b/app/api/project-directories/route.ts
new file mode 100644
index 00000000..cebbe465
--- /dev/null
+++ b/app/api/project-directories/route.ts
@@ -0,0 +1,41 @@
+import { NextResponse } from "next/server";
+import { allowFileRoot } from "@/lib/file-access";
+import {
+  addProjectDirectory,
+  normalizeProjectDirectory,
+  readProjectDirectories,
+  removeProjectDirectory,
+} from "@/lib/project-directories";
+
+export const dynamic = "force-dynamic";
+
+export async function GET() {
+  const projects = readProjectDirectories();
+  projects.forEach(allowFileRoot);
+  return NextResponse.json({ projects });
+}
+
+export async function POST(request: Request) {
+  try {
+    const body = await request.json() as { cwd?: unknown };
+    const cwd = normalizeProjectDirectory(body.cwd);
+    allowFileRoot(cwd);
+    return NextResponse.json({ projects: addProjectDirectory(cwd), cwd });
+  } catch (error) {
+    console.error("保存 Pi Web 项目目录失败", error);
+    return NextResponse.json({ error: error instanceof Error ? error.message : String(error) }, { status: 400 });
+  }
+}
+
+export async function DELETE(request: Request) {
+  try {
+    const body = await request.json() as { cwd?: unknown };
+    if (typeof body.cwd !== "string" || !body.cwd.trim()) {
+      return NextResponse.json({ error: "cwd required" }, { status: 400 });
+    }
+    return NextResponse.json({ projects: removeProjectDirectory(body.cwd.trim()) });
+  } catch (error) {
+    console.error("移除 Pi Web 项目目录失败", error);
+    return NextResponse.json({ error: error instanceof Error ? error.message : String(error) }, { status: 500 });
+  }
+}
diff --git a/app/layout.tsx b/app/layout.tsx
index 83ce2f5f..6d5001a8 100644
--- a/app/layout.tsx
+++ b/app/layout.tsx
@@ -1,5 +1,6 @@
 import type { Metadata, Viewport } from "next";
 import { Noto_Sans_Mono } from "next/font/google";
+import Script from "next/script";
 import { PwaRegistration } from "@/components/PwaRegistration";
 import "katex/dist/katex.min.css";
 import "./globals.css";
@@ -10,6 +11,25 @@ const notoSansMono = Noto_Sans_Mono({
   display: "swap",
 });
 
+const DEV_PWA_CLEANUP_SCRIPT = `(function(){
+  if (!("serviceWorker" in navigator)) return;
+  Promise.all([
+    navigator.serviceWorker.getRegistrations().then(function(registrations){
+      return Promise.all(registrations.map(function(registration){ return registration.unregister(); }));
+    }),
+    ("caches" in window) ? caches.keys().then(function(keys){
+      return Promise.all(keys.filter(function(key){ return key.indexOf("pi-web-") === 0; }).map(function(key){ return caches.delete(key); }));
+    }) : Promise.resolve()
+  ]).then(function(){
+    if (navigator.serviceWorker.controller && !sessionStorage.getItem("pi-web-dev-sw-cleaned")) {
+      sessionStorage.setItem("pi-web-dev-sw-cleaned", "1");
+      location.reload();
+    } else {
+      sessionStorage.removeItem("pi-web-dev-sw-cleaned");
+    }
+  }).catch(function(error){ console.error("PWA 开发缓存清理失败", error); });
+})();`;
+
 export const metadata: Metadata = {
   title: "Pi Web",
   description: "Pi Web interface for the pi coding agent",
@@ -62,6 +82,9 @@ export default function RootLayout({
             __html: `(function(){try{var t=localStorage.getItem("pi-theme");if(t==="dark")document.documentElement.classList.add("dark")}catch(e){}})();`,
           }}
         />
+        {process.env.NODE_ENV !== "production" && (
+          <Script id="dev-pwa-cleanup" strategy="beforeInteractive" dangerouslySetInnerHTML={{ __html: DEV_PWA_CLEANUP_SCRIPT }} />
+        )}
       </head>
       <body translate="no" className="notranslate" style={{ height: "100dvh", display: "flex", flexDirection: "column" }}>
         {children}
diff --git a/components/AppShell.session-navigation.test.mjs b/components/AppShell.session-navigation.test.mjs
new file mode 100644
index 00000000..18acb9bd
--- /dev/null
+++ b/components/AppShell.session-navigation.test.mjs
@@ -0,0 +1,14 @@
+import assert from "node:assert/strict";
+import fs from "node:fs";
+import test from "node:test";
+
+const source = fs.readFileSync(new URL("./AppShell.tsx", import.meta.url), "utf8");
+
+test("重复选择当前会话不会重挂载聊天窗口", () => {
+  assert.match(source, /activeSessionIdRef\.current === session\.id\) return/);
+});
+
+test("会话切换只更新地址栏而不发起 App Router 导航", () => {
+  assert.match(source, /window\.history\.replaceState\(window\.history\.state/);
+  assert.match(source, /replaceSessionUrl\(session\.id\)/);
+});
diff --git a/components/AppShell.tsx b/components/AppShell.tsx
index 9b093335..404ec2ca 100644
--- a/components/AppShell.tsx
+++ b/components/AppShell.tsx
@@ -46,6 +46,14 @@ type AutoNameStatus =
 const TOP_BAR_ICON_BUTTON_SIZE = 36;
 const LANGUAGE_MENU_WIDTH = 176;
 
+/** 仅同步地址栏，不触发 App Router 的服务端导航和聊天区域重复挂载。 */
+function replaceSessionUrl(sessionId: string | null): void {
+  const url = new URL(window.location.href);
+  if (sessionId) url.searchParams.set("session", sessionId);
+  else url.searchParams.delete("session");
+  window.history.replaceState(window.history.state, "", `${url.pathname}${url.search}${url.hash}`);
+}
+
 export function AppShell() {
   const router = useRouter();
   const searchParams = useSearchParams();
@@ -56,6 +64,8 @@ export function AppShell() {
   const [selectedSession, setSelectedSession] = useState<SessionInfo | null>(null);
   // When user clicks +, we only store the cwd — no fake session id
   const [newSessionCwd, setNewSessionCwd] = useState<string | null>(null);
+  // 仅当前浏览器内记录每个 cwd 的一个未发送新会话，不写入服务端。
+  const [pendingNewSessionCwds, setPendingNewSessionCwds] = useState<Set<string>>(() => new Set());
   const [initialCwdStatus, setInitialCwdStatus] = useState<"idle" | "validating" | "ready" | "error">(
     () => initialNavigation.requestedCwd ? "validating" : "idle",
   );
@@ -347,6 +357,7 @@ export function AppShell() {
   }, [router, selectedSession]);
 
   const handleSelectSession = useCallback((session: SessionInfo, isRestore = false) => {
+    if (!isRestore && activeSessionIdRef.current === session.id) return;
     setNewSessionCwd(null);
     setSelectedSession(session);
     setSessionKey((k) => k + 1);
@@ -360,14 +371,27 @@ export function AppShell() {
       suppressCwdBumpRef.current = true;
     }
     // Skip router.replace when restoring from URL — the param is already correct
-    // and calling replace in production Next.js triggers a Suspense remount loop
+    // and route navigation would trigger an unnecessary RSC request.
     if (!isRestore) {
-      router.replace(`?session=${encodeURIComponent(session.id)}`, { scroll: false });
+      replaceSessionUrl(session.id);
     }
-  }, [router, isMobile]);
+  }, [isMobile]);
 
   const handleNewSession = useCallback((_sessionId: string, cwd: string) => {
     setSelectedSession(null);
+    // 同一目录只复用已有的未发送会话；draft-store 负责恢复输入内容。
+    if (pendingNewSessionCwds.has(cwd)) {
+      setNewSessionCwd(cwd);
+      setSessionKey((k) => k + 1);
+      replaceSessionUrl(null);
+      return;
+    }
+    setPendingNewSessionCwds((current) => {
+      if (current.has(cwd)) return current;
+      const next = new Set(current);
+      next.add(cwd);
+      return next;
+    });
     setNewSessionCwd(cwd);
     setSessionKey((k) => k + 1);
     setBranchTree([]);
@@ -375,8 +399,8 @@ export function AppShell() {
     setSystemPrompt(null);
     setActiveTopPanel(null);
     if (isMobile) setSidebarOpen(false);
-    router.replace("/", { scroll: false });
-  }, [router, isMobile]);
+    replaceSessionUrl(null);
+  }, [isMobile, pendingNewSessionCwds]);
 
   // Global keyboard shortcuts (handles Esc, Ctrl+Alt+N etc.)
   useGlobalKeyboardShortcuts({
@@ -402,11 +426,17 @@ export function AppShell() {
   // Called by ChatWindow when a new session gets its real id from pi
   const handleSessionCreated = useCallback((session: SessionInfo) => {
     setNewSessionCwd(null);
+    setPendingNewSessionCwds((current) => {
+      if (!current.has(session.cwd)) return current;
+      const next = new Set(current);
+      next.delete(session.cwd);
+      return next;
+    });
     setSelectedSession(session);
     setRefreshKey((k) => k + 1);
     hydrateSelectedSession(session.id);
-    router.replace(`?session=${encodeURIComponent(session.id)}`, { scroll: false });
-  }, [router, hydrateSelectedSession]);
+    replaceSessionUrl(session.id);
+  }, [hydrateSelectedSession]);
 
   const handleAgentEnd = useCallback(() => {
     setRefreshKey((k) => k + 1);
@@ -1467,10 +1497,18 @@ export function AppShell() {
         {/* Chat content */}
         <div style={{ flex: 1, overflow: "hidden", position: "relative" }}>
           {showChat ? (
-            <ChatWindow
+      <ChatWindow
               key={sessionKey}
               session={selectedSession}
-              newSessionCwd={effectiveNewSessionCwd}
+        newSessionCwd={effectiveNewSessionCwd}
+        onNewSessionCwdChange={(cwd) => {
+          setPendingNewSessionCwds((current) => {
+            const next = new Set(current);
+            next.add(cwd);
+            return next;
+          });
+          setNewSessionCwd(cwd);
+        }}
               onAgentEnd={handleAgentEnd}
               onSessionCreated={handleSessionCreated}
               onSessionForked={handleSessionForked}
diff --git a/components/ChatInput.test.mjs b/components/ChatInput.test.mjs
index 7d1e6757..4839754e 100644
--- a/components/ChatInput.test.mjs
+++ b/components/ChatInput.test.mjs
@@ -97,3 +97,25 @@ test("renders compact errors above the input as a wrapping alert", () => {
   assert.match(html, /white-space:pre-wrap/);
   assert.ok(html.indexOf('role="alert"') < html.indexOf("<textarea"));
 });
+
+test("renders the worktree selector only for a new session", () => {
+  const html = renderToStaticMarkup(
+    React.createElement(
+      I18nProvider,
+      null,
+      React.createElement(ChatInput, {
+        onSend() {},
+        onAbort() {},
+        isStreaming: false,
+        cwd: "/repo",
+        newSessionCwd: "/repo-wt",
+        newSessionWorktrees: [
+          { path: "/repo", branch: "main", isMain: true },
+          { path: "/repo-wt", branch: "feature/test", isMain: false },
+        ],
+      }),
+    ),
+  );
+  assert.match(html, /选择 worktree/);
+  assert.match(html, /feature\/test/);
+});
diff --git a/components/ChatInput.tsx b/components/ChatInput.tsx
index cc0f5267..0fd8d3ab 100644
--- a/components/ChatInput.tsx
+++ b/components/ChatInput.tsx
@@ -3,6 +3,7 @@
 import React, { useRef, useState, useCallback, useEffect, useImperativeHandle, forwardRef, KeyboardEvent } from "react";
 import type { BuiltinSlashCommandResult, CompactResultInfo, QueuedMessages, SlashCommandInfo } from "@/hooks/useAgentSession";
 import { clearDraft, getDraft, setDraft, type ChatDraftImage } from "@/lib/draft-store";
+import { applySlashSelection, findSlashQuery } from "@/lib/slash-command";
 import {
   MAX_ATTACHED_IMAGE_BYTES,
   MAX_ATTACHED_IMAGES,
@@ -65,9 +66,16 @@ interface Props {
   soundEnabled?: boolean;
   onSoundToggle?: () => void;
   onAudioUnlock?: () => void;
+  notificationEnabled?: boolean;
+  notificationPermission?: NotificationPermission | "unsupported";
+  onNotificationToggle?: () => void;
   draftKey?: string;
   /** Session working directory — enables the @ file autocomplete menu */
   cwd?: string | null;
+  /** 新会话可选的 worktree 列表；已有会话不显示此选择器。 */
+  newSessionWorktrees?: { path: string; branch: string | null; isMain: boolean }[];
+  newSessionCwd?: string | null;
+  onNewSessionCwdChange?: (cwd: string) => void;
 }
 
 export interface ChatInputHandle {
@@ -81,6 +89,7 @@ const TOOL_PRESETS = ["off", "default", "full"] as const;
 const TOOL_PRESET_MAP: Record<"off" | "default" | "full", "none" | "default" | "full"> = { off: "none", default: "default", full: "full" };
 const COMPOSITION_END_ENTER_GRACE_MS = 100;
 const MODEL_FILTER_THRESHOLD = 8;
+const TEXTAREA_MAX_HEIGHT = 200;
 const MODEL_OPTION_COLLATOR = new Intl.Collator(undefined, { numeric: true, sensitivity: "base" });
 
 function compareModelOptions(a: ModelOption, b: ModelOption): number {
@@ -283,10 +292,13 @@ export const ChatInput = forwardRef<ChatInputHandle, Props>(function ChatInput({
   retryInfo, queuedMessages, inputHistory = [], onRecallQueue,
   slashCommands, slashCommandsLoading, onLoadSlashCommands,
   onBuiltinCommand,
-  soundEnabled, onSoundToggle, onAudioUnlock,
+  soundEnabled, onSoundToggle, onAudioUnlock, notificationEnabled, notificationPermission, onNotificationToggle,
   onPromptWithStreamingBehavior,
   draftKey,
   cwd,
+  newSessionWorktrees,
+  newSessionCwd,
+  onNewSessionCwdChange,
 }: Props, ref) {
   const { t } = useI18n();
   const isMobile = useIsMobile();
@@ -305,6 +317,7 @@ export const ChatInput = forwardRef<ChatInputHandle, Props>(function ChatInput({
   const bashExcluded = bashMode && trimmedValue.startsWith("!!");
   const [slashMenuOpen, setSlashMenuOpen] = useState(false);
   const [slashActiveIndex, setSlashActiveIndex] = useState(0);
+  const [slashCursor, setSlashCursor] = useState<number | null>(null);
   const [atQuery, setAtQuery] = useState<AtQueryMatch | null>(null);
   const [atMenuOpen, setAtMenuOpen] = useState(false);
   const [atActiveIndex, setAtActiveIndex] = useState(0);
@@ -334,9 +347,27 @@ export const ChatInput = forwardRef<ChatInputHandle, Props>(function ChatInput({
   const valueRef = useRef(value);
   const attachedImagesRef = useRef(attachedImages);
   const pendingImageCountRef = useRef(0);
+  const resizeFrameRef = useRef<number | null>(null);
+  const textareaAtMaxHeightRef = useRef(false);
   valueRef.current = value;
   attachedImagesRef.current = attachedImages;
 
+  const resizeTextarea = useCallback((force = false) => {
+    const ta = textareaRef.current;
+    if (!ta || (!force && textareaAtMaxHeightRef.current)) return;
+    if (resizeFrameRef.current !== null) cancelAnimationFrame(resizeFrameRef.current);
+    resizeFrameRef.current = requestAnimationFrame(() => {
+      resizeFrameRef.current = null;
+      const textarea = textareaRef.current;
+      if (!textarea) return;
+      if (!force && textarea.scrollHeight <= textarea.clientHeight) return;
+      if (force) textarea.style.height = "auto";
+      const height = Math.min(textarea.scrollHeight, TEXTAREA_MAX_HEIGHT);
+      textarea.style.height = `${height}px`;
+      textareaAtMaxHeightRef.current = textarea.scrollHeight > TEXTAREA_MAX_HEIGHT;
+    });
+  }, []);
+
   useImperativeHandle(ref, () => ({
     insertIfEmpty(text: string) {
       const ta = textareaRef.current;
@@ -459,6 +490,7 @@ export const ChatInput = forwardRef<ChatInputHandle, Props>(function ChatInput({
     clearImages();
     if (textareaRef.current) {
       textareaRef.current.style.height = "auto";
+      textareaAtMaxHeightRef.current = false;
     }
   }, [clearImages, draftKey]);
 
@@ -493,14 +525,12 @@ export const ChatInput = forwardRef<ChatInputHandle, Props>(function ChatInput({
   }, [draftKey]);
 
   useEffect(() => {
-    const ta = textareaRef.current;
-    if (!ta) return;
-    ta.style.height = "auto";
-    if (value) ta.style.height = `${Math.min(ta.scrollHeight, 200)}px`;
-  }, [value]);
+    resizeTextarea(true);
+  }, [draftKey, resizeTextarea]);
 
   useEffect(() => {
     return () => {
+      if (resizeFrameRef.current !== null) cancelAnimationFrame(resizeFrameRef.current);
       attachedImagesRef.current.forEach(revokeImagePreview);
     };
   }, []);
@@ -521,13 +551,15 @@ export const ChatInput = forwardRef<ChatInputHandle, Props>(function ChatInput({
     clearInput();
   }, [value, attachedImages, isStreaming, onBuiltinCommand, onSend, clearInput, onAudioUnlock]);
 
-  const slashQuery = value.startsWith("/") && !/\s/.test(value.slice(1))
-    ? value.slice(1).toLowerCase()
-    : null;
+  const slashInputEnd = Math.min(slashCursor ?? value.length, value.length);
+  const slashInputPrefix = value.slice(0, slashInputEnd);
+  const slash = findSlashQuery(slashInputPrefix);
+  const slashQuery = slash?.query ?? null;
 
   const filteredSlashCommands = (() => {
     if (slashQuery === null) return [];
-    const commands = [...(isStreaming ? [] : BUILTIN_SLASH_COMMANDS), ...(slashCommands ?? [])];
+    const commands = [...(isStreaming ? [] : BUILTIN_SLASH_COMMANDS), ...(slashCommands ?? [])]
+      .filter((command) => !slash?.inline || command.source === "skill");
     return [...commands]
       .filter((command) => {
         const name = command.name.toLowerCase();
@@ -729,19 +761,26 @@ export const ChatInput = forwardRef<ChatInputHandle, Props>(function ChatInput({
   }, []);
 
   const applySlashCommand = useCallback((command: SlashCommandPaletteItem) => {
-    const nextValue = `/${command.name} `;
+    const inputEnd = Math.min(slashCursor ?? value.length, value.length);
+    const inputPrefix = value.slice(0, inputEnd);
+    const activeSlash = findSlashQuery(inputPrefix);
+    if (!activeSlash) return;
+    const selectedPrefix = applySlashSelection(inputPrefix, activeSlash, command.name);
+    const nextValue = selectedPrefix + value.slice(inputEnd);
+    const nextCursor = selectedPrefix.length;
     setValue(nextValue);
+    setSlashCursor(nextCursor);
     setSlashMenuOpen(false);
     setSlashActiveIndex(0);
     requestAnimationFrame(() => {
       const ta = textareaRef.current;
       if (!ta) return;
       ta.focus();
-      ta.setSelectionRange(nextValue.length, nextValue.length);
+      ta.setSelectionRange(nextCursor, nextCursor);
       ta.style.height = "auto";
       ta.style.height = `${Math.min(ta.scrollHeight, 200)}px`;
     });
-  }, []);
+  }, [slashCursor, value]);
 
   const sendQueued = useCallback((mode: "steer" | "followup") => {
     const msg = value.trim();
@@ -929,12 +968,15 @@ export const ChatInput = forwardRef<ChatInputHandle, Props>(function ChatInput({
     [isStreaming, onSteer, onFollowUp, onAbort, slashMenuOpen, slashQuery, filteredSlashCommands, slashActiveIndex, applySlashCommand, sendQueued, handleSend, getNextSlashIndex, atMenuOpen, atQuery, atMatches, atActiveIndex, applyAtCompletion, historyMenuOpen, inputHistory, historyActiveIndex, applyHistoryInput, value]
   );
 
-  const handleInput = useCallback(() => {
-    const ta = textareaRef.current;
-    if (!ta) return;
-    ta.style.height = "auto";
-    ta.style.height = `${Math.min(ta.scrollHeight, 200)}px`;
-  }, []);
+  const handleInput = useCallback((event: React.FormEvent<HTMLTextAreaElement>) => {
+    const inputType = (event.nativeEvent as InputEvent).inputType ?? "";
+    // 达到最大高度后，普通输入不会改变控件尺寸；删除、换行和粘贴时才重新测量。
+    const mayShrinkOrReflow = inputType.startsWith("delete")
+      || inputType === "insertLineBreak"
+      || inputType === "insertParagraph"
+      || inputType === "insertFromPaste";
+    resizeTextarea(mayShrinkOrReflow);
+  }, [resizeTextarea]);
 
   const handlePaste = useCallback((e: React.ClipboardEvent) => {
     const items = Array.from(e.clipboardData?.items ?? []);
@@ -1076,6 +1118,23 @@ export const ChatInput = forwardRef<ChatInputHandle, Props>(function ChatInput({
       <div style={{ maxWidth: 820, margin: "0 auto" }}>
         <ModelErrorBanner error={modelError} />
         <ModelScopeWarningBanner warnings={modelScopeWarnings} />
+        {newSessionWorktrees && newSessionWorktrees.length > 0 && (
+          <label style={{ display: "flex", alignItems: "center", gap: 7, margin: "0 0 6px 4px", color: "var(--text-muted)", fontSize: 11 }}>
+            <span aria-hidden="true">⌘</span>
+            <select
+              aria-label="选择 worktree"
+              value={newSessionCwd ?? cwd ?? ""}
+              onChange={(event) => onNewSessionCwdChange?.(event.target.value)}
+              style={{ minWidth: 0, maxWidth: "100%", border: 0, outline: 0, background: "transparent", color: "var(--text-muted)", fontFamily: "var(--font-mono)", fontSize: 11, cursor: "pointer" }}
+            >
+              {newSessionWorktrees.map((worktree) => (
+                <option key={worktree.path} value={worktree.path}>
+                  {worktree.branch ?? worktree.path}{worktree.isMain ? " · 主分支" : ""}
+                </option>
+              ))}
+            </select>
+          </label>
+        )}
         {/* Queued steering / follow-up messages (delivered by pi on upcoming turns) */}
         {((queuedMessages?.steering.length ?? 0) + (queuedMessages?.followUp.length ?? 0)) > 0 && (
           <div style={{
@@ -1557,11 +1616,15 @@ export const ChatInput = forwardRef<ChatInputHandle, Props>(function ChatInput({
             value={value}
             onChange={(e) => {
               setValue(e.target.value);
+              const textarea = e.currentTarget;
+              // 某些移动端/自动填充输入事件会在光标更新前触发 change。
+              requestAnimationFrame(() => setSlashCursor(textarea.selectionStart));
               setHistoryMenuOpen(false);
               updateAtQuery(e.target.value, e.target.selectionStart);
             }}
             onSelect={(e) => {
               const el = e.currentTarget;
+              setSlashCursor(el.selectionStart);
               updateAtQuery(el.value, el.selectionStart);
             }}
             onKeyDown={handleKeyDown}
@@ -2243,6 +2306,50 @@ export const ChatInput = forwardRef<ChatInputHandle, Props>(function ChatInput({
                 )}
               </button>
             )}
+            {onNotificationToggle !== undefined && notificationPermission !== "unsupported" && (
+              <button
+                onClick={onNotificationToggle}
+                title={notificationEnabled
+                  ? t("chat.disableNotification")
+                  : notificationPermission === "denied"
+                    ? t("chat.notificationBlocked")
+                    : t("chat.enableNotification")}
+                aria-label={notificationEnabled
+                  ? t("chat.disableNotification")
+                  : notificationPermission === "denied"
+                    ? t("chat.notificationBlocked")
+                    : t("chat.enableNotification")}
+                style={{
+                  display: "flex", alignItems: "center", justifyContent: "center",
+                  width: 32,
+                  height: 32,
+                  padding: 0,
+                  background: "none",
+                  border: "none",
+                  borderRadius: 9,
+                  color: notificationEnabled ? "var(--text-muted)" : "var(--text-dim)",
+                  cursor: "pointer",
+                  opacity: notificationEnabled ? 1 : 0.55,
+                  transition: "background 0.12s, color 0.12s, opacity 0.12s",
+                }}
+                onMouseEnter={(e) => {
+                  e.currentTarget.style.background = "var(--bg-hover)";
+                  e.currentTarget.style.color = "var(--text)";
+                  e.currentTarget.style.opacity = "1";
+                }}
+                onMouseLeave={(e) => {
+                  e.currentTarget.style.background = "none";
+                  e.currentTarget.style.color = notificationEnabled ? "var(--text-muted)" : "var(--text-dim)";
+                  e.currentTarget.style.opacity = notificationEnabled ? "1" : "0.55";
+                }}
+              >
+                <svg width="13" height="13" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true">
+                  <path d="M18 8a6 6 0 0 0-12 0c0 7-3 7-3 9h18c0-2-3-2-3-9" />
+                  <path d="M13.73 21a2 2 0 0 1-3.46 0" />
+                  {!notificationEnabled && <line x1="4" y1="4" x2="20" y2="20" />}
+                </svg>
+              </button>
+            )}
             {isMobile && controlsMenuOpen && (
               <button
                 type="button"
diff --git a/components/ChatWindow.notification.test.mjs b/components/ChatWindow.notification.test.mjs
new file mode 100644
index 00000000..350c901a
--- /dev/null
+++ b/components/ChatWindow.notification.test.mjs
@@ -0,0 +1,16 @@
+import assert from "node:assert/strict";
+import { readFile } from "node:fs/promises";
+import test from "node:test";
+
+const source = await readFile(new URL("./ChatWindow.tsx", import.meta.url), "utf8");
+
+test("extension input dialogs send one session notification per request", () => {
+  assert.match(source, /notifiedExtensionDialogIdRef\.current === extensionDialog\.id/);
+  assert.match(source, /notifySessionRef\.current\(/);
+  assert.match(source, /extensionDialog\.method === "confirm"/);
+});
+
+test("custom ask dialogs also send one session notification per request", () => {
+  assert.match(source, /notifiedExtensionCustomUiIdRef\.current === extensionCustomUi\.id/);
+  assert.match(source, /extensionCustomUi\.closed/);
+});
diff --git a/components/ChatWindow.tsx b/components/ChatWindow.tsx
index 893d70ce..a89b928f 100644
--- a/components/ChatWindow.tsx
+++ b/components/ChatWindow.tsx
@@ -12,6 +12,8 @@ import { ExtensionStatusBar } from "./ExtensionStatusBar";
 import { useI18n } from "@/hooks/useI18n";
 import { useAgentSession, type AgentPhase, type NoticeItem } from "@/hooks/useAgentSession";
 import { useAudio } from "@/hooks/useAudio";
+import { useCompletionNotification } from "@/hooks/useCompletionNotification";
+import notificationStyles from "./CompletionNotificationPrompt.module.css";
 import { useDragDrop } from "@/hooks/useDragDrop";
 import { useIsMobile } from "@/hooks/useIsMobile";
 import type { SessionStatsInfo } from "@/lib/pi-types";
@@ -37,6 +39,7 @@ interface Props {
   onSessionStatsPanelOpen?: () => void;
   onContextUsageChange?: (usage: { percent: number | null; contextWindow: number; tokens: number | null } | null) => void;
   onOpenFile?: (filePath: string) => void;
+  onNewSessionCwdChange?: (cwd: string) => void;
 }
 
 function phaseLabel(phase: AgentPhase, t: (key: string, params?: Record<string, string | number>) => string): string {
@@ -87,6 +90,25 @@ function getUserInputText(message: AgentMessage): string | null {
   return text.length > 0 ? text : null;
 }
 
+function compactNotificationText(text: string, maxLength: number): string {
+  const compact = text.replace(/\s+/g, " ").trim();
+  return compact.length > maxLength ? `${compact.slice(0, maxLength)}…` : compact;
+}
+
+function getAssistantNotificationPreview(messages: AgentMessage[]): string {
+  for (let index = messages.length - 1; index >= 0; index--) {
+    const message = messages[index];
+    if (message.role !== "assistant") continue;
+    const text = splitFinalAssistantBlocks(message as AssistantMessage).answerBlocks
+      .filter((block): block is Extract<AssistantContentBlock, { type: "text" }> => block.type === "text")
+      .map((block) => block.text)
+      .join(" ");
+    const preview = compactNotificationText(text, 80);
+    if (preview) return preview;
+  }
+  return "";
+}
+
 function countToolCalls(messages: AgentMessage[], indices: number[]): number {
   let count = 0;
   for (const idx of indices) {
@@ -170,9 +192,13 @@ function ProcessDetailsGroup({ messageCount, toolCallCount, children, t }: { mes
   );
 }
 
-export function ChatWindow({ session, newSessionCwd, onAgentEnd, onSessionCreated, onSessionForked, modelsRefreshKey, chatInputRef, onBranchDataChange, onSystemPromptChange, onSessionStatsChange, onSessionStatsPanelOpen, onContextUsageChange, onOpenFile }: Props) {
+export function ChatWindow({ session, newSessionCwd, onAgentEnd, onSessionCreated, onSessionForked, modelsRefreshKey, chatInputRef, onBranchDataChange, onSystemPromptChange, onSessionStatsChange, onSessionStatsPanelOpen, onContextUsageChange, onOpenFile, onNewSessionCwdChange }: Props) {
   const { t } = useI18n();
   const { soundEnabled, onSoundToggle, playDoneSound, unlockAudio } = useAudio();
+  const {
+    notificationEnabled, notificationPermission, showNotificationPrompt,
+    onNotificationToggle, dismissNotificationPrompt, notifySession,
+  } = useCompletionNotification();
   const isMobile = useIsMobile();
 
   // Wrap onAgentEnd to play the completion sound. This is more reliable than
@@ -183,12 +209,22 @@ export function ChatWindow({ session, newSessionCwd, onAgentEnd, onSessionCreate
   playDoneSoundRef.current = playDoneSound;
   const soundEnabledRef = useRef(soundEnabled);
   soundEnabledRef.current = soundEnabled;
+  const notifySessionRef = useRef(notifySession);
+  notifySessionRef.current = notifySession;
+  const notificationSessionIdRef = useRef<string | null>(session?.id ?? null);
+  const notificationTitleRef = useRef("");
+  const notificationPreviewRef = useRef("");
   const wrappedOnAgentEnd = useCallback(() => {
     if (soundEnabledRef.current) {
       playDoneSoundRef.current();
     }
+    void notifySessionRef.current(
+      notificationTitleRef.current || t("i18n.newSession"),
+      notificationPreviewRef.current || t("chat.notificationDoneBody"),
+      notificationSessionIdRef.current,
+    );
     onAgentEnd?.();
-  }, [onAgentEnd]);
+  }, [onAgentEnd, t]);
 
   // 稳定化 onEditContent 引用，配合 React.memo 防止历史消息重渲染
   const handleEditContent = useCallback((content: string) => {
@@ -201,7 +237,7 @@ export function ChatWindow({ session, newSessionCwd, onAgentEnd, onSessionCreate
     retryInfo, contextUsage, forkingEntryId,
     isCompacting, compactError, compactResult, displayModel: displayModelValue, sessionStats,
     slashCommands, slashCommandsLoading, queuedMessages,
-    notices, extensionDialog, extensionCustomUi, extensionStatuses, extensionWidgets, respondToExtensionUi, sendExtensionCustomInput,
+    notices, dismissNotice, extensionDialog, extensionCustomUi, extensionStatuses, extensionWidgets, respondToExtensionUi, sendExtensionCustomInput,
     isAutoModelSelection,
     agentPhase,
     isNew,
@@ -216,6 +252,34 @@ export function ChatWindow({ session, newSessionCwd, onAgentEnd, onSessionCreate
     session, newSessionCwd, onAgentEnd: wrappedOnAgentEnd, onSessionCreated, onSessionForked,
     modelsRefreshKey, chatInputRef, onBranchDataChange, onSystemPromptChange, onSessionStatsPanelOpen,
   });
+  notificationSessionIdRef.current = sessionIdRef.current ?? session?.id ?? null;
+  notificationTitleRef.current = compactNotificationText(
+    session?.name || session?.firstMessage || t("i18n.newSession"),
+    48,
+  );
+  notificationPreviewRef.current = getAssistantNotificationPreview(messages);
+  const notifiedExtensionDialogIdRef = useRef<string | null>(null);
+  const notifiedExtensionCustomUiIdRef = useRef<string | null>(null);
+  useEffect(() => {
+    if (!extensionDialog || notifiedExtensionDialogIdRef.current === extensionDialog.id) return;
+    notifiedExtensionDialogIdRef.current = extensionDialog.id;
+    void notifySessionRef.current(
+      compactNotificationText(extensionDialog.title, 48) || t("chat.notificationAttentionTitle"),
+      extensionDialog.method === "confirm"
+        ? compactNotificationText(extensionDialog.message, 80) || t("chat.notificationAttentionBody")
+        : t("chat.notificationAttentionBody"),
+      notificationSessionIdRef.current,
+    );
+  }, [extensionDialog, t]);
+  useEffect(() => {
+    if (!extensionCustomUi || extensionCustomUi.closed || notifiedExtensionCustomUiIdRef.current === extensionCustomUi.id) return;
+    notifiedExtensionCustomUiIdRef.current = extensionCustomUi.id;
+    void notifySessionRef.current(
+      t("chat.notificationAttentionTitle"),
+      t("chat.notificationAttentionBody"),
+      notificationSessionIdRef.current,
+    );
+  }, [extensionCustomUi, t]);
   const sessionBusy = agentRunning || bashRunning;
 
   // Register the abort handler for the global Esc shortcut
@@ -324,6 +388,23 @@ export function ChatWindow({ session, newSessionCwd, onAgentEnd, onSessionCreate
 
   const isEmptyNew = isNew && messages.length === 0 && !streamState.isStreaming && !sessionBusy;
   const messageCwd = session?.cwd ?? newSessionCwd ?? undefined;
+  const [newSessionWorktrees, setNewSessionWorktrees] = useState<{ path: string; branch: string | null; isMain: boolean }[]>([]);
+  useEffect(() => {
+    if (session || !newSessionCwd) {
+      setNewSessionWorktrees([]);
+      return;
+    }
+    const controller = new AbortController();
+    fetch(`/api/worktrees?cwd=${encodeURIComponent(newSessionCwd)}`, { signal: controller.signal })
+      .then((response) => response.ok ? response.json() as Promise<{ worktrees?: typeof newSessionWorktrees }> : Promise.reject(new Error(`HTTP ${response.status}`)))
+      .then((data) => setNewSessionWorktrees(data.worktrees ?? []))
+      .catch((error: unknown) => {
+        if (error instanceof DOMException && error.name === "AbortError") return;
+        console.error("加载新会话 worktree 失败", error);
+        setNewSessionWorktrees([]);
+      });
+    return () => controller.abort();
+  }, [newSessionCwd, session]);
 
   const availableThinkingLevels = displayModelValue
     ? (modelThinkingLevels[`${displayModelValue.provider}:${displayModelValue.modelId}`] ?? null)
@@ -371,8 +452,14 @@ export function ChatWindow({ session, newSessionCwd, onAgentEnd, onSessionCreate
       soundEnabled={soundEnabled}
       onSoundToggle={onSoundToggle}
       onAudioUnlock={unlockAudio}
+      notificationEnabled={notificationEnabled}
+      notificationPermission={notificationPermission}
+      onNotificationToggle={onNotificationToggle}
       draftKey={session?.id ?? (newSessionCwd ? `new:${newSessionCwd}` : undefined)}
       cwd={session?.cwd ?? newSessionCwd}
+      newSessionWorktrees={!session ? newSessionWorktrees : undefined}
+      newSessionCwd={!session ? newSessionCwd : undefined}
+      onNewSessionCwdChange={onNewSessionCwdChange}
     />
   );
 
@@ -403,6 +490,22 @@ export function ChatWindow({ session, newSessionCwd, onAgentEnd, onSessionCreate
       onDragLeave={handleDragLeave}
       onDrop={handleDrop}
     >
+      {showNotificationPrompt && (
+        <aside className={notificationStyles.prompt} role="dialog" aria-labelledby="completion-notification-title">
+          <div className={notificationStyles.copy}>
+            <strong id="completion-notification-title">{t("chat.notificationPromptTitle")}</strong>
+            <span>{t("chat.notificationPromptBody")}</span>
+          </div>
+          <div className={notificationStyles.actions}>
+            <button type="button" className={notificationStyles.laterButton} onClick={dismissNotificationPrompt}>
+              {t("chat.notificationPromptLater")}
+            </button>
+            <button type="button" className={notificationStyles.enableButton} onClick={onNotificationToggle}>
+              {t("chat.notificationPromptEnable")}
+            </button>
+          </div>
+        </aside>
+      )}
       {isDragOver && !sessionBusy && (
         <div className="pointer-events-none absolute inset-0 z-50 flex animate-[drop-zone-in_0.15s_ease_both] items-center justify-center bg-[rgba(37,99,235,0.06)] backdrop-blur-[1px]">
           <div className="pointer-events-none absolute inset-0 flex items-center justify-center">
@@ -477,7 +580,7 @@ export function ChatWindow({ session, newSessionCwd, onAgentEnd, onSessionCreate
                 </span>
               </div>
             </div>
-            <NoticeShelf notices={notices} align="right" />
+            <NoticeShelf notices={notices} onDismiss={dismissNotice} align="right" />
             {chatInputElement}
           </div>
         </div>
@@ -496,7 +599,7 @@ export function ChatWindow({ session, newSessionCwd, onAgentEnd, onSessionCreate
           }}
         >
           <div style={{ maxWidth: 820, margin: "0 auto" }}>
-            <NoticeShelf notices={notices} floating align="right" />
+            <NoticeShelf notices={notices} onDismiss={dismissNotice} floating align="right" />
           </div>
         </div>
         <div ref={scrollContainerRef} className="flex-1 overflow-y-auto pt-4 [scrollbar-width:none]">
@@ -512,15 +615,8 @@ export function ChatWindow({ session, newSessionCwd, onAgentEnd, onSessionCreate
                 }
               }
 
-              let lastUserIdx = -1;
-              for (let i = messages.length - 1; i >= 0; i--) {
-                if (messages[i].role === "user") { lastUserIdx = i; break; }
-              }
-              // Anchor for live-tail detection: the last user message, or a
-              // compaction summary when compaction has replaced it mid-turn.
-              // Computed independently from lastUserIdx (which is kept for the
-              // scroll-to-user ref) because a compaction summary can sit after
-              // the last user message and anchor the still-streaming segment.
+              // Anchor for live-tail detection and scroll positioning: the last
+              // user message, or a compaction summary when compaction replaced it.
               let lastAnchorIdx = -1;
               for (let i = messages.length - 1; i >= 0; i--) {
                 if (isGroupAnchor(messages[i])) { lastAnchorIdx = i; break; }
@@ -536,7 +632,7 @@ export function ChatWindow({ session, newSessionCwd, onAgentEnd, onSessionCreate
 
               const attachVisibleRef = (idx: number, refIndex: number) => (el: HTMLDivElement | null) => {
                 messageRefs.current[refIndex] = el;
-                if (idx === lastUserIdx) { (lastUserMsgRef as { current: HTMLDivElement | null }).current = el; }
+                if (idx === lastAnchorIdx) { (lastUserMsgRef as { current: HTMLDivElement | null }).current = el; }
               };
 
               const renderMessage = (idx: number, options: { attachRef?: boolean; keyPrefix?: string; messageOverride?: AgentMessage; showTimestamp?: boolean } = {}): ReactNode => {
@@ -581,6 +677,13 @@ export function ChatWindow({ session, newSessionCwd, onAgentEnd, onSessionCreate
                     sessionId={session?.id ?? sessionIdRef.current ?? undefined}
                   />
                 );
+                if (idx === lastAnchorIdx && (!isVisible || currentRefIdx === undefined)) {
+                  return (
+                    <div key={`${keyPrefix}-${idx}`} ref={(el) => { (lastUserMsgRef as { current: HTMLDivElement | null }).current = el; }}>
+                      {view}
+                    </div>
+                  );
+                }
                 if (!isVisible || options.attachRef === false || currentRefIdx === undefined) return view;
                 return (
                   <div key={`${keyPrefix}-${idx}`} ref={attachVisibleRef(idx, currentRefIdx)}>
@@ -590,6 +693,7 @@ export function ChatWindow({ session, newSessionCwd, onAgentEnd, onSessionCreate
               };
 
               const rendered: ReactNode[] = [];
+              let liveTailStartIndex: number | null = null;
               for (let idx = 0; idx < messages.length;) {
                 const msg = messages[idx];
                 if (!isGroupAnchor(msg)) {
@@ -614,6 +718,7 @@ export function ChatWindow({ session, newSessionCwd, onAgentEnd, onSessionCreate
 
                 const isLiveTail = (sessionBusy || streamState.isStreaming) && endIdx === messages.length && userIdx === lastAnchorIdx;
                 if (isLiveTail) {
+                  liveTailStartIndex = rendered.length;
                   for (let renderIdx = userIdx; renderIdx < endIdx; renderIdx++) {
                     rendered.push(renderMessage(renderIdx));
                   }
@@ -671,7 +776,13 @@ export function ChatWindow({ session, newSessionCwd, onAgentEnd, onSessionCreate
                 }
                 idx = endIdx;
               }
-              const { startIndex, hasMore } = getVisibleRenderWindow(rendered.length, visibleCount);
+              const window = getVisibleRenderWindow(rendered.length, visibleCount);
+              // 运行中的单轮会话可能包含超过一页的工具消息。必须连同该轮锚点一起渲染，
+              // 否则定位引用会被分页裁掉，恢复会话时只能滚进底部预留的空白区域。
+              const startIndex = liveTailStartIndex === null
+                ? window.startIndex
+                : Math.min(window.startIndex, liveTailStartIndex);
+              const hasMore = startIndex > 0;
               return (
                 <>
                   {hasMore && (
@@ -711,11 +822,11 @@ export function ChatWindow({ session, newSessionCwd, onAgentEnd, onSessionCreate
               />
             )}
 
+            <div ref={messagesEndRef} />
+
             {agentRunning && (
               <div style={{ height: scrollContainerRef.current ? scrollContainerRef.current.clientHeight : "80vh" }} />
             )}
-
-            <div ref={messagesEndRef} />
             </div>
           </div>
         </div>
@@ -776,7 +887,8 @@ function ExtensionWidgets({ widgets }: { widgets: Array<{ key: string; lines: st
   );
 }
 
-function NoticeShelf({ notices, floating = false, align = "left" }: { notices: NoticeItem[]; floating?: boolean; align?: "left" | "right" }) {
+function NoticeShelf({ notices, onDismiss, floating = false, align = "left" }: { notices: NoticeItem[]; onDismiss: (id: string) => void; floating?: boolean; align?: "left" | "right" }) {
+  const { t } = useI18n();
   if (notices.length === 0) return null;
   return (
     <div
@@ -785,6 +897,7 @@ function NoticeShelf({ notices, floating = false, align = "left" }: { notices: N
         flexDirection: "column",
         alignItems: align === "right" ? "flex-end" : "stretch",
         marginBottom: floating ? 0 : 10,
+        pointerEvents: "auto",
       }}
     >
       {notices.map((notice, index) => {
@@ -796,8 +909,11 @@ function NoticeShelf({ notices, floating = false, align = "left" }: { notices: N
               ? "#10b981"
               : "var(--accent)";
         return (
-          <div
+          <button
             key={notice.id}
+            type="button"
+            onClick={() => onDismiss(notice.id)}
+            title={t("i18n.close")}
             className="notice-shelf-item"
             style={{
               display: "flex",
@@ -824,6 +940,8 @@ function NoticeShelf({ notices, floating = false, align = "left" }: { notices: N
                 ? "notice-shelf-out 0.18s ease-in forwards"
                 : "notice-shelf-in 0.18s ease-out both",
               padding: "0 12px",
+              cursor: "pointer",
+              textAlign: "left",
             }}
           >
             <span
@@ -838,7 +956,7 @@ function NoticeShelf({ notices, floating = false, align = "left" }: { notices: N
             <span style={{ padding: "14px 0", minWidth: 0, maxWidth: "100%", overflow: "hidden", textOverflow: "ellipsis", whiteSpace: "nowrap" }}>
               {notice.message}
             </span>
-          </div>
+          </button>
         );
       })}
     </div>
diff --git a/components/CompletionNotificationPrompt.module.css b/components/CompletionNotificationPrompt.module.css
new file mode 100644
index 00000000..be43ed42
--- /dev/null
+++ b/components/CompletionNotificationPrompt.module.css
@@ -0,0 +1,87 @@
+.prompt {
+  position: absolute;
+  right: 16px;
+  bottom: 92px;
+  z-index: 45;
+  display: flex;
+  align-items: center;
+  gap: 18px;
+  max-width: min(430px, calc(100% - 32px));
+  padding: 12px;
+  border: 1px solid var(--border);
+  border-radius: 8px;
+  background: var(--bg);
+  color: var(--text);
+  box-shadow: 0 12px 32px color-mix(in srgb, var(--text) 16%, transparent);
+}
+
+.copy {
+  display: flex;
+  min-width: 0;
+  flex-direction: column;
+  gap: 3px;
+}
+
+.copy strong {
+  font-size: 13px;
+  letter-spacing: 0;
+}
+
+.copy span {
+  color: var(--text-muted);
+  font-size: 12px;
+  line-height: 1.4;
+}
+
+.actions {
+  display: flex;
+  flex-shrink: 0;
+  gap: 6px;
+}
+
+.actions button {
+  min-height: 34px;
+  padding: 0 11px;
+  border-radius: 6px;
+  font-size: 12px;
+  font-weight: 600;
+  letter-spacing: 0;
+  cursor: pointer;
+}
+
+.laterButton {
+  border: 1px solid var(--border);
+  background: transparent;
+  color: var(--text-muted);
+}
+
+.enableButton {
+  border: 1px solid var(--accent);
+  background: var(--accent);
+  color: #ffffff;
+}
+
+.actions button:focus-visible {
+  outline: 2px solid var(--accent);
+  outline-offset: 2px;
+}
+
+@media (max-width: 640px) {
+  .prompt {
+    right: 10px;
+    bottom: 82px;
+    left: 10px;
+    max-width: none;
+    align-items: stretch;
+    flex-direction: column;
+    gap: 10px;
+  }
+
+  .actions {
+    justify-content: flex-end;
+  }
+
+  .actions button {
+    min-height: 40px;
+  }
+}
diff --git a/components/MessageView.tsx b/components/MessageView.tsx
index d73bee37..b763bebb 100644
--- a/components/MessageView.tsx
+++ b/components/MessageView.tsx
@@ -7,6 +7,8 @@ import { useI18n } from "@/hooks/useI18n";
 import { parseCompactionSummary } from "@/lib/compaction-summary";
 import { getAssistantErrorMessage, isEmptyThinkingBlock } from "@/lib/message-display";
 import { parseUnifiedPatch, type SplitDiffCell } from "@/lib/patch";
+import { parseSkillMessage } from "@/lib/skill-block";
+import { getLongUserMessageStats } from "@/lib/long-user-message";
 import type {
   AgentMessage,
   UserMessage,
@@ -24,6 +26,18 @@ import type {
 const MAX_THINKING_CACHE_ENTRIES = 100;
 const thinkingContentCache = new Map<string, Promise<string>>();
 
+function downloadTextFile(content: string): void {
+  const url = URL.createObjectURL(new Blob([content], { type: "text/plain;charset=utf-8" }));
+  const link = document.createElement("a");
+  link.href = url;
+  link.download = "prompt.txt";
+  link.style.display = "none";
+  document.body.appendChild(link);
+  link.click();
+  link.remove();
+  setTimeout(() => URL.revokeObjectURL(url), 0);
+}
+
 function loadThinkingContent(sessionId: string, entryId: string, blockIndex: number): Promise<string> {
   const key = `${sessionId}:${entryId}:${blockIndex}`;
   const cached = thinkingContentCache.get(key);
@@ -151,6 +165,7 @@ function UserMessageView({ message, cwd, onOpenFile, entryId, onFork, forking, o
   const { t } = useI18n();
   const [hovered, setHovered] = useState(false);
   const [copied, setCopied] = useState(false);
+  const [longMessageExpanded, setLongMessageExpanded] = useState(false);
 
   const content =
     typeof message.content === "string"
@@ -159,6 +174,12 @@ function UserMessageView({ message, cwd, onOpenFile, entryId, onFork, forking, o
           .filter((b): b is TextContent => b.type === "text")
           .map((b) => b.text)
           .join("\n");
+  const skillMessage = parseSkillMessage(content);
+  const displayContent = skillMessage?.userMessage ?? (skillMessage ? "" : content);
+  const skillCommand = skillMessage
+    ? `${skillMessage.skills.map((skill) => `/skill:${skill.name}`).join(" ")}${skillMessage.userMessage ? ` ${skillMessage.userMessage}` : ""}`
+    : null;
+  const longMessageStats = getLongUserMessageStats(displayContent);
 
   const imageBlocks: ImageContent[] =
     typeof message.content === "string"
@@ -170,7 +191,7 @@ function UserMessageView({ message, cwd, onOpenFile, entryId, onFork, forking, o
   const canNavigate = !!prevAssistantEntryId && !!onNavigate;
 
   const copyContent = () => {
-    copyText(content).then(() => {
+    copyText(skillCommand ?? content).then(() => {
       setCopied(true);
       setTimeout(() => setCopied(false), 1500);
     });
@@ -222,7 +243,53 @@ function UserMessageView({ message, cwd, onOpenFile, entryId, onFork, forking, o
               })}
             </div>
           )}
-          {content && <MarkdownBody className="markdown-user-message" cwd={cwd} onOpenFile={onOpenFile}>{content}</MarkdownBody>}
+          {skillMessage && (
+            <div style={{ fontFamily: "var(--font-mono)", fontSize: 13, fontWeight: 600, marginBottom: displayContent ? 6 : 0 }}>
+              {skillMessage.skills.map((skill) => <div key={`${skill.name}:${skill.location}`}>[skill] {skill.name}</div>)}
+            </div>
+          )}
+          {displayContent && longMessageStats.compact ? (
+            <div style={{ minWidth: 0 }}>
+              <div style={{ display: "flex", alignItems: "center", gap: 9, minHeight: 34 }}>
+                <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="1.7" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true" style={{ flexShrink: 0, color: "var(--text-muted)" }}>
+                  <path d="M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8Z" />
+                  <path d="M14 2v6h6" />
+                  <path d="M8 13h8M8 17h6" />
+                </svg>
+                <div style={{ flex: 1, minWidth: 0 }}>
+                  <div style={{ fontFamily: "var(--font-mono)", fontSize: 12, fontWeight: 600 }}>prompt.txt</div>
+                  <div style={{ color: "var(--text-dim)", fontSize: 11 }}>
+                    {t("chat.longMessageStats", {
+                      characters: longMessageStats.characters.toLocaleString(),
+                      lines: longMessageStats.lines.toLocaleString(),
+                    })}
+                  </div>
+                </div>
+                <button type="button" onClick={() => setLongMessageExpanded((expanded) => !expanded)} style={{ padding: "3px 7px", border: "none", background: "none", color: "var(--accent)", cursor: "pointer", fontSize: 11, whiteSpace: "nowrap" }}>
+                  {t(longMessageExpanded ? "chat.collapseLongMessage" : "chat.viewLongMessage")}
+                </button>
+                <button type="button" onClick={copyContent} title={t("i18n.copyMessage")} aria-label={t("i18n.copyMessage")} style={{ display: "flex", width: 26, height: 26, alignItems: "center", justifyContent: "center", padding: 0, border: "none", background: "none", color: copied ? "var(--accent)" : "var(--text-muted)", cursor: "pointer" }}>
+                  {copied ? (
+                    <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="1.8" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true"><path d="m5 12 4 4L19 6" /></svg>
+                  ) : (
+                    <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="1.8" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true"><rect x="9" y="9" width="13" height="13" rx="2" /><path d="M5 15H4a2 2 0 0 1-2-2V4a2 2 0 0 1 2-2h9a2 2 0 0 1 2 2v1" /></svg>
+                  )}
+                </button>
+                <button type="button" onClick={() => downloadTextFile(displayContent)} title={t("i18n.downloadFile")} aria-label={t("i18n.downloadFile")} style={{ display: "flex", width: 26, height: 26, alignItems: "center", justifyContent: "center", padding: 0, border: "none", background: "none", color: "var(--text-muted)", cursor: "pointer" }}>
+                  <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="1.8" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true">
+                    <path d="M12 3v12" /><path d="m7 10 5 5 5-5" /><path d="M5 21h14" />
+                  </svg>
+                </button>
+              </div>
+              {longMessageExpanded && (
+                <pre style={{ maxHeight: 420, margin: "8px 0 0", paddingTop: 8, overflow: "auto", borderTop: "1px solid rgba(59,130,246,0.16)", whiteSpace: "pre-wrap", overflowWrap: "anywhere", fontFamily: "var(--font-mono)", fontSize: 12, lineHeight: 1.55 }}>
+                  {displayContent}
+                </pre>
+              )}
+            </div>
+          ) : displayContent ? (
+            <MarkdownBody className="markdown-user-message" cwd={cwd} onOpenFile={onOpenFile}>{displayContent}</MarkdownBody>
+          ) : null}
         </div>
 
       </div>
@@ -278,7 +345,7 @@ function UserMessageView({ message, cwd, onOpenFile, entryId, onFork, forking, o
             }}>
               {canNavigate && (
                 <button
-                  onClick={() => { onNavigate!(prevAssistantEntryId!); onEditContent?.(content); }}
+                  onClick={() => { onNavigate!(prevAssistantEntryId!); onEditContent?.(skillCommand ?? content); }}
                    title={t("i18n.editFromHereTitle")}
                   style={{
                     display: "flex", alignItems: "center", gap: 4,
diff --git a/components/PwaRegistration.module.css b/components/PwaRegistration.module.css
new file mode 100644
index 00000000..da42b5b3
--- /dev/null
+++ b/components/PwaRegistration.module.css
@@ -0,0 +1,61 @@
+.updatePrompt {
+  position: fixed;
+  right: max(16px, env(safe-area-inset-right));
+  top: max(16px, env(safe-area-inset-top));
+  z-index: 1000;
+  display: flex;
+  align-items: center;
+  gap: 18px;
+  min-height: 52px;
+  padding: 8px 8px 8px 16px;
+  border: 1px solid var(--border);
+  border-radius: 8px;
+  background: var(--bg);
+  color: var(--text);
+  box-shadow: 0 12px 32px color-mix(in srgb, var(--text) 16%, transparent);
+  font-size: 13px;
+  font-weight: 600;
+}
+
+.actions {
+  display: flex;
+  gap: 6px;
+}
+
+.actions button {
+  min-height: 36px;
+  padding: 0 12px;
+  border-radius: 6px;
+  font: inherit;
+  cursor: pointer;
+}
+
+.laterButton {
+  border: 1px solid var(--border);
+  background: transparent;
+  color: var(--text-muted);
+}
+
+.updateButton {
+  border: 1px solid var(--accent);
+  background: var(--accent);
+  color: #ffffff;
+}
+
+.actions button:focus-visible {
+  outline: 2px solid var(--accent);
+  outline-offset: 2px;
+}
+
+@media (max-width: 640px) {
+  .updatePrompt {
+    right: max(10px, env(safe-area-inset-right));
+    top: max(10px, env(safe-area-inset-top));
+    left: max(10px, env(safe-area-inset-left));
+    justify-content: space-between;
+  }
+
+  .actions button {
+    min-height: 44px;
+  }
+}
diff --git a/components/PwaRegistration.tsx b/components/PwaRegistration.tsx
index d5c6af9e..1495205c 100644
--- a/components/PwaRegistration.tsx
+++ b/components/PwaRegistration.tsx
@@ -1,33 +1,127 @@
 "use client";
 
-import { useEffect } from "react";
+import { useCallback, useEffect, useRef, useState } from "react";
+import styles from "./PwaRegistration.module.css";
+
+const UPDATE_INTERVAL_MS = 60 * 60 * 1000;
+const CACHE_PREFIX = "pi-web-";
 
 export function PwaRegistration() {
+  const [waitingWorker, setWaitingWorker] = useState<ServiceWorker | null>(null);
+  const refreshingRef = useRef(false);
+
   useEffect(() => {
-    if (process.env.NODE_ENV !== "production" || !("serviceWorker" in navigator)) {
+    if (!("serviceWorker" in navigator)) {
+      return;
+    }
+
+    if (process.env.NODE_ENV !== "production") {
+      // 旧版本可能已在同源开发地址注册，继续控制页面会让 HMR 加载缓存的 chunk。
+      void navigator.serviceWorker.getRegistrations().then((registrations) => (
+        Promise.all(registrations.map((registration) => registration.unregister()))
+      )).catch((error: unknown) => {
+        console.error("PWA Service Worker 注销失败", error);
+      });
+      if ("caches" in window) {
+        void caches.keys().then((keys) => (
+          Promise.all(keys.filter((key) => key.startsWith(CACHE_PREFIX)).map((key) => caches.delete(key)))
+        )).catch((error: unknown) => {
+          console.error("PWA 缓存清理失败", error);
+        });
+      }
       return;
     }
 
-    const register = () => {
-      const appVersion = process.env.NEXT_PUBLIC_APP_VERSION ?? "dev";
-      const scriptUrl = `/sw.js?v=${encodeURIComponent(appVersion)}`;
+    const appVersion = process.env.NEXT_PUBLIC_APP_VERSION ?? "dev";
+    const scriptUrl = `/sw.js?v=${encodeURIComponent(appVersion)}`;
+    let registration: ServiceWorkerRegistration | null = null;
+    let intervalId: ReturnType<typeof setInterval> | null = null;
+    let disposed = false;
 
-      void navigator.serviceWorker.register(scriptUrl, {
-        scope: "/",
-        updateViaCache: "none",
-      }).catch((error: unknown) => {
-        console.error("Failed to register the Pi Web service worker:", error);
+    const watchInstallingWorker = (worker: ServiceWorker) => {
+      worker.addEventListener("statechange", () => {
+        if (!disposed && worker.state === "installed" && navigator.serviceWorker.controller) {
+          setWaitingWorker(worker);
+        }
       });
     };
 
+    const handleUpdateFound = () => {
+      if (registration?.installing) watchInstallingWorker(registration.installing);
+    };
+
+    const checkForUpdate = () => {
+      if (document.visibilityState === "visible") {
+        void registration?.update().catch((error: unknown) => {
+          console.error("PWA Service Worker 更新检查失败", error);
+        });
+      }
+    };
+
+    const register = async () => {
+      try {
+        const nextRegistration = await navigator.serviceWorker.register(scriptUrl, {
+          scope: "/",
+          updateViaCache: "none",
+        });
+        if (disposed) return;
+
+        registration = nextRegistration;
+        if (registration.waiting && navigator.serviceWorker.controller) {
+          setWaitingWorker(registration.waiting);
+        }
+        registration.addEventListener("updatefound", handleUpdateFound);
+        document.addEventListener("visibilitychange", checkForUpdate);
+        intervalId = setInterval(checkForUpdate, UPDATE_INTERVAL_MS);
+        checkForUpdate();
+      } catch (error) {
+        console.error("PWA Service Worker 注册失败", error);
+      }
+    };
+
+    const handleLoad = () => void register();
     if (document.readyState === "complete") {
-      register();
-      return;
+      void register();
+    } else {
+      window.addEventListener("load", handleLoad, { once: true });
     }
 
-    window.addEventListener("load", register, { once: true });
-    return () => window.removeEventListener("load", register);
+    const handleControllerChange = () => {
+      if (refreshingRef.current) return;
+      refreshingRef.current = true;
+      window.location.reload();
+    };
+    navigator.serviceWorker.addEventListener("controllerchange", handleControllerChange);
+
+    return () => {
+      disposed = true;
+      window.removeEventListener("load", handleLoad);
+      document.removeEventListener("visibilitychange", checkForUpdate);
+      registration?.removeEventListener("updatefound", handleUpdateFound);
+      if (intervalId) clearInterval(intervalId);
+      navigator.serviceWorker.removeEventListener("controllerchange", handleControllerChange);
+    };
   }, []);
 
-  return null;
+  const applyUpdate = useCallback(() => {
+    if (!waitingWorker) return;
+    refreshingRef.current = false;
+    waitingWorker.postMessage({ type: "SKIP_WAITING" });
+  }, [waitingWorker]);
+
+  if (!waitingWorker) return null;
+
+  return (
+    <aside className={styles.updatePrompt} role="status" aria-live="polite">
+      <span>发现新版本</span>
+      <div className={styles.actions}>
+        <button type="button" className={styles.laterButton} onClick={() => setWaitingWorker(null)}>
+          稍后
+        </button>
+        <button type="button" className={styles.updateButton} onClick={applyUpdate}>
+          立即更新
+        </button>
+      </div>
+    </aside>
+  );
 }
diff --git a/components/SessionSidebar.test.mjs b/components/SessionSidebar.test.mjs
index 58856318..fda979d8 100644
--- a/components/SessionSidebar.test.mjs
+++ b/components/SessionSidebar.test.mjs
@@ -18,9 +18,34 @@ test("does not register row-level session deletion shortcuts", () => {
   assert.doesNotMatch(sessionItemSource, /tabIndex=\{0\}/);
 });
 
+test("does not add an empty new session to the server-backed list", () => {
+  assert.doesNotMatch(source, /optimisticSession/);
+  assert.doesNotMatch(source, /setOptimisticSessions/);
+  assert.match(source, /const visibleSessions = allSessions/);
+  assert.match(source, /session\.worktreeBranch \? session\.cwd/);
+});
+
+test("does not reselect the active session", () => {
+  assert.match(source, /if \(s\.id === selectedSessionId\) return/);
+});
+
 test("polls running sessions only while the tab is visible", () => {
   assert.doesNotMatch(source, /new EventSource\("\/api\/agent\/running\/events"\)/);
   assert.match(source, /fetch\("\/api\/agent\/running"/);
   assert.match(source, /document\.visibilityState !== "visible"/);
   assert.match(source, /document\.addEventListener\("visibilitychange", onVisibilityChange\)/);
 });
+
+test("renders projects as persistent directory rows with per-project session actions", () => {
+  assert.match(source, /visibleProjects\.map\(\(project\) =>/);
+  assert.match(source, /projectName\(project\)/);
+  assert.match(source, /onClick=\{\(\) => handleNewSession\(project\)\}/);
+  assert.match(source, /buildSessionTree\(projectSessions\)/);
+  assert.match(source, /projectName\(left\)\.localeCompare\(projectName\(right\)/);
+  assert.match(source, /setProjectPendingRemoval\(project\)/);
+  assert.match(source, /sidebar\.removeProjectDescription/);
+  assert.match(source, /const showWorktreeSwitcher = false/);
+  assert.match(source, /useState<string\[]>\(\[\]\)/);
+  assert.match(source, /fetch\("\/api\/project-directories", \{ cache: "no-store" \}\)/);
+  assert.match(source, /setKnownProjects\(projects\)/);
+});
diff --git a/components/SessionSidebar.tsx b/components/SessionSidebar.tsx
index 0514b55e..6d80c211 100644
--- a/components/SessionSidebar.tsx
+++ b/components/SessionSidebar.tsx
@@ -109,6 +109,7 @@ interface WorktreeState {
 }
 
 const UNREAD_SESSIONS_STORAGE_KEY = "pi-web:unread-session-ids";
+const PROJECT_DIRECTORIES_STORAGE_KEY = "pi-web:project-directories";
 const RUNNING_SESSIONS_POLL_MS = 2500;
 
 function loadUnreadSessionIds(): Set<string> {
@@ -134,6 +135,16 @@ function saveUnreadSessionIds(ids: Set<string>): void {
   }
 }
 
+function loadLegacyProjectDirectories(): string[] {
+  if (typeof window === "undefined") return [];
+  try {
+    const value = JSON.parse(window.localStorage.getItem(PROJECT_DIRECTORIES_STORAGE_KEY) ?? "[]") as unknown;
+    return Array.isArray(value) ? value.filter((item): item is string => typeof item === "string") : [];
+  } catch {
+    return [];
+  }
+}
+
 function formatRelativeTime(dateStr: string): string {
   const date = new Date(dateStr);
   const now = new Date();
@@ -172,6 +183,12 @@ function displayCwd(cwd: string, homeDir?: string): string {
   return (homeDir && cwd.startsWith(homeDir)) ? "~" + cwd.slice(homeDir.length) : cwd;
 }
 
+/** 项目树只展示目录名，完整路径保留在悬浮提示中。 */
+function projectName(cwd: string): string {
+  const trimmed = cwd.replace(/[\\/]+$/, "");
+  return trimmed.slice(Math.max(trimmed.lastIndexOf("/"), trimmed.lastIndexOf("\\")) + 1) || trimmed;
+}
+
 /**
  * Path label that ellipsizes on the LEFT, keeping the (most relevant) trailing
  * segments visible: "…orkspace/pi-web". Shows as much of the path as fits
@@ -389,15 +406,18 @@ export function SessionSidebar({ selectedSessionId, onSelectSession, onNewSessio
   const [loading, setLoading] = useState(true);
   const [error, setError] = useState<string | null>(null);
   const [selectedCwd, setSelectedCwd] = useState<string | null>(null);
+  // 服务端与客户端首屏都从空列表开始，挂载后再恢复本地目录，避免 hydration 不一致。
+  const [knownProjects, setKnownProjects] = useState<string[]>([]);
   const [homeDir, setHomeDir] = useState<string>("");
-  const [dropdownOpen, setDropdownOpen] = useState(false);
-  const [projectFilter, setProjectFilter] = useState("");
+  const [collapsedProjects, setCollapsedProjects] = useState<Set<string>>(() => new Set());
+  const [projectPendingRemoval, setProjectPendingRemoval] = useState<string | null>(null);
+  const [projectRemovalBusy, setProjectRemovalBusy] = useState(false);
+  const [projectRemovalError, setProjectRemovalError] = useState<string | null>(null);
   const [wtFilter, setWtFilter] = useState("");
   const [customPathOpen, setCustomPathOpen] = useState(false);
   const [customPathValue, setCustomPathValue] = useState("");
   const [customPathError, setCustomPathError] = useState<string | null>(null);
   const [customPathValidating, setCustomPathValidating] = useState(false);
-  const dropdownRef = useRef<HTMLDivElement>(null);
   // Worktree switcher state
   const [worktreeState, setWorktreeState] = useState<WorktreeState | null>(null);
   const [wtDropdownOpen, setWtDropdownOpen] = useState(false);
@@ -406,7 +426,6 @@ export function SessionSidebar({ selectedSessionId, onSelectSession, onNewSessio
   const [wtError, setWtError] = useState<string | null>(null);
   const [wtBusy, setWtBusy] = useState(false);
   const [wtConfirmRemove, setWtConfirmRemove] = useState<string | null>(null);
-  const [worktreeLoadingCwd, setWorktreeLoadingCwd] = useState<string | null>(null);
   const wtDropdownRef = useRef<HTMLDivElement>(null);
   const wtNewInputRef = useRef<HTMLInputElement>(null);
   const [explorerOpen, setExplorerOpen] = useState(true);
@@ -471,6 +490,36 @@ export function SessionSidebar({ selectedSessionId, onSelectSession, onNewSessio
     saveUnreadSessionIds(unreadSessionIds);
   }, [unreadSessionIds]);
 
+  useEffect(() => {
+    let cancelled = false;
+    const load = async () => {
+      try {
+        const response = await fetch("/api/project-directories", { cache: "no-store" });
+        const data = await response.json() as { projects?: string[]; error?: string };
+        if (!response.ok || data.error) throw new Error(data.error ?? `HTTP ${response.status}`);
+
+        let projects = data.projects ?? [];
+        const legacyProjects = loadLegacyProjectDirectories();
+        for (const cwd of legacyProjects) {
+          const migration = await fetch("/api/project-directories", {
+            method: "POST",
+            headers: { "Content-Type": "application/json" },
+            body: JSON.stringify({ cwd }),
+          });
+          if (!migration.ok) continue;
+          const migrated = await migration.json() as { projects?: string[] };
+          projects = migrated.projects ?? projects;
+        }
+        window.localStorage.removeItem(PROJECT_DIRECTORIES_STORAGE_KEY);
+        if (!cancelled) setKnownProjects(projects);
+      } catch (error) {
+        console.error("加载 Pi Web 项目目录失败", error);
+      }
+    };
+    void load();
+    return () => { cancelled = true; };
+  }, []);
+
   useEffect(() => {
     let stopped = false;
     let timer: ReturnType<typeof setTimeout> | null = null;
@@ -609,16 +658,13 @@ export function SessionSidebar({ selectedSessionId, onSelectSession, onNewSessio
   useLayoutEffect(() => {
     if (!selectedCwd) {
       setWorktreeState(null);
-      setWorktreeLoadingCwd(null);
       return;
     }
     let cancelled = false;
-    setWorktreeLoadingCwd(selectedCwd);
     fetch(`/api/worktrees?cwd=${encodeURIComponent(selectedCwd)}`)
       .then((r) => r.json())
       .then((d: { projectRoot?: string; isGit?: boolean; isTopLevel?: boolean; worktrees?: WorktreeEntry[]; error?: string }) => {
         if (cancelled) return;
-        setWorktreeLoadingCwd(null);
         if (d.error || !d.projectRoot) {
           setWorktreeState(null);
           return;
@@ -633,7 +679,6 @@ export function SessionSidebar({ selectedSessionId, onSelectSession, onNewSessio
       })
       .catch(() => {
         if (!cancelled) {
-          setWorktreeLoadingCwd(null);
           setWorktreeState(null);
         }
       });
@@ -669,20 +714,23 @@ export function SessionSidebar({ selectedSessionId, onSelectSession, onNewSessio
     setCustomPathValidating(true);
     setCustomPathError(null);
     try {
-      const res = await fetch("/api/cwd/validate", {
+      const res = await fetch("/api/project-directories", {
         method: "POST",
         headers: { "Content-Type": "application/json" },
         body: JSON.stringify({ cwd: path }),
       });
-      const data = await res.json().catch(() => ({})) as { cwd?: string; error?: string };
+      const data = await res.json().catch(() => ({})) as { cwd?: string; projects?: string[]; error?: string };
       if (!res.ok || data.error) {
         setCustomPathError(data.error ?? `HTTP ${res.status}`);
         return;
       }
       setSelectedCwd(data.cwd ?? path);
+      setKnownProjects((current) => {
+        const cwd = data.cwd ?? path;
+        return data.projects ?? [cwd, ...current.filter((project) => project !== cwd)];
+      });
       setCustomPathOpen(false);
       setCustomPathValue("");
-      setDropdownOpen(false);
     } catch (e) {
       setCustomPathError(e instanceof Error ? e.message : String(e));
     } finally {
@@ -693,24 +741,7 @@ export function SessionSidebar({ selectedSessionId, onSelectSession, onNewSessio
   const handleCustomPathClick = useCallback(() => {
     setCustomPathOpen(true);
     setCustomPathError(null);
-    setDropdownOpen(false);
-  }, []);
-  const handleDefaultCwd = useCallback(async () => {
-    try {
-      const res = await fetch("/api/default-cwd", { method: "POST" });
-      const data = await res.json() as { cwd?: string; error?: string };
-      if (data.cwd) {
-        setSelectedCwd(data.cwd);
-        setCustomPathOpen(false);
-        setCustomPathValue("");
-        setCustomPathError(null);
-        setDropdownOpen(false);
-      }
-    } catch {
-      // ignore
-    }
   }, []);
-
   const handleCreateWorktree = useCallback(async () => {
     const branch = wtNewBranch.trim();
     if (!branch || wtBusy || !worktreeState) return;
@@ -780,10 +811,6 @@ export function SessionSidebar({ selectedSessionId, onSelectSession, onNewSessio
   // Close dropdowns on outside click
   useEffect(() => {
     const handler = (e: MouseEvent) => {
-      if (dropdownRef.current && !dropdownRef.current.contains(e.target as Node)) {
-        setDropdownOpen(false);
-        setProjectFilter("");
-      }
       if (wtDropdownRef.current && !wtDropdownRef.current.contains(e.target as Node)) {
         setWtDropdownOpen(false);
         setWtNewOpen(false);
@@ -802,62 +829,81 @@ export function SessionSidebar({ selectedSessionId, onSelectSession, onNewSessio
   // works when the prop value won't change — e.g. re-clicking the already
   // open session after manually switching worktrees.
   const handleSelectSessionFromList = useCallback((s: SessionInfo) => {
+    if (s.id === selectedSessionId) return;
     if (s.cwd) setSelectedCwd(s.cwd);
+    if (!s.path) return;
     onSelectSession(s);
-  }, [onSelectSession]);
-
-  const handleNewSession = useCallback(() => {
-    if (!selectedCwd) return;
-    // Generate a temporary UUID client-side — no backend call needed.
-    // Pi will be spawned lazily when the user sends the first message.
-    const tempId = typeof crypto.randomUUID === "function"
-      ? crypto.randomUUID()
-      : `${Date.now().toString(36)}-${Math.random().toString(36).slice(2)}-${Math.random().toString(36).slice(2)}`;
-    onNewSession?.(tempId, selectedCwd);
-  }, [selectedCwd, onNewSession]);
-
-  const recentProjects = getRecentProjects(allSessions);
-  const showProjectFilter = recentProjects.length > 8;
-  const visibleProjects = projectFilter.trim()
-    ? recentProjects.filter((p) => p.toLowerCase().includes(projectFilter.trim().toLowerCase()))
-    : recentProjects;
-
-  // Sessions of every worktree in the selected project are shown together
+  }, [onSelectSession, selectedSessionId]);
+
+  const handleNewSession = useCallback((cwd: string) => {
+    setSelectedCwd(cwd);
+    onNewSession?.(cwd, cwd);
+  }, [onNewSession]);
+
+  const visibleSessions = allSessions;
+  const displayProject = (session: SessionInfo) => session.worktreeBranch ? session.cwd : (session.projectRoot ?? session.cwd);
+  const recentProjects = [...new Set(visibleSessions.map(displayProject))];
   const selectedProject = projectRootFor(selectedCwd);
-  const filteredSessions = selectedProject
-    ? allSessions.filter((s) => (s.projectRoot ?? s.cwd) === selectedProject)
-    : allSessions;
-  const showWorktreeSwitcher = Boolean(
-    worktreeState?.isGit
-    && worktreeState.isTopLevel
-    && selectedCwd
-    && selectedProject === worktreeState.projectRoot
-  );
-  const worktreeGuide = selectedCwd
-    && worktreeState
-    && selectedProject === worktreeState.projectRoot
-    && !showWorktreeSwitcher
-    ? (worktreeState.isGit
-        ? {
-             label: t("sidebar.openRepoRoot"),
-             title: t("sidebar.openRepoRootTitle"),
-          }
-        : {
-             label: t("sidebar.gitRepoRootOnly"),
-             title: t("sidebar.gitRepoRootOnlyTitle"),
-          })
-    : null;
-  const worktreeLoading = Boolean(selectedCwd && worktreeLoadingCwd === selectedCwd);
-  const inactiveWorktreeSelector = worktreeGuide
-    ?? (worktreeLoading && !showWorktreeSwitcher
-      ? {
-           label: t("sidebar.worktrees"),
-           title: t("sidebar.checkingWorktrees"),
+  const selectedDisplayProject = visibleSessions.find((session) => session.cwd === selectedCwd)
+    ? displayProject(visibleSessions.find((session) => session.cwd === selectedCwd)!)
+    : selectedProject;
+  const visibleProjects = [...new Set([
+    ...(selectedProject ? [selectedProject] : []),
+    ...recentProjects,
+    ...knownProjects,
+  ])].sort((left, right) => projectName(left).localeCompare(projectName(right), undefined, {
+    sensitivity: "base",
+    numeric: true,
+  }));
+  // Worktree 选择只放在新会话输入框中，侧边栏不再提供第二个切换入口。
+  const showWorktreeSwitcher = false;
+  const inactiveWorktreeSelector = (() => null as { label: string; title: string } | null)();
+
+  const handleRemoveProject = useCallback(async () => {
+    if (!projectPendingRemoval || projectRemovalBusy) return;
+
+    setProjectRemovalBusy(true);
+    setProjectRemovalError(null);
+    const sessions = allSessions.filter((session) => (session.projectRoot ?? session.cwd) === projectPendingRemoval);
+    try {
+      for (const session of sessions) {
+        const response = await fetch(`/api/sessions/${encodeURIComponent(session.id)}`, { method: "DELETE" });
+        if (!response.ok && response.status !== 404) {
+          const data = await response.json().catch(() => ({})) as { error?: string };
+          throw new Error(data.error ?? `HTTP ${response.status}`);
         }
-      : null);
+        onSessionDeleted?.(session.id);
+      }
 
-  // Build parent-child tree within the filtered set
-  const sessionTree = buildSessionTree(filteredSessions);
+      const removeResponse = await fetch("/api/project-directories", {
+        method: "DELETE",
+        headers: { "Content-Type": "application/json" },
+        body: JSON.stringify({ cwd: projectPendingRemoval }),
+      });
+      const removeData = await removeResponse.json().catch(() => ({})) as { projects?: string[]; error?: string };
+      if (!removeResponse.ok || removeData.error) throw new Error(removeData.error ?? `HTTP ${removeResponse.status}`);
+
+      setAllSessions((current) => current.filter((session) => (session.projectRoot ?? session.cwd) !== projectPendingRemoval));
+      setKnownProjects(removeData.projects ?? []);
+      setCollapsedProjects((current) => {
+        const next = new Set(current);
+        next.delete(projectPendingRemoval);
+        return next;
+      });
+      if (selectedProject === projectPendingRemoval) {
+        const nextProject = visibleProjects.find((project) => project !== projectPendingRemoval);
+        if (nextProject) await commitCustomPath(nextProject);
+        else setSelectedCwd(null);
+      }
+      setProjectPendingRemoval(null);
+    } catch (cause) {
+      console.error("移除项目目录失败", cause);
+      setProjectRemovalError(cause instanceof Error ? cause.message : String(cause));
+      await loadSessions(false);
+    } finally {
+      setProjectRemovalBusy(false);
+    }
+  }, [allSessions, commitCustomPath, loadSessions, onSessionDeleted, projectPendingRemoval, projectRemovalBusy, selectedProject, visibleProjects]);
 
   return (
     <div style={{ display: "flex", flexDirection: "column", height: "100%", overflow: "hidden" }}>
@@ -872,6 +918,37 @@ export function SessionSidebar({ selectedSessionId, onSelectSession, onNewSessio
           onSelect={(path) => void commitCustomPath(path)}
         />
       )}
+      {projectPendingRemoval && (
+        <div
+          role="dialog"
+          aria-modal="true"
+          aria-labelledby="remove-project-title"
+          style={{ position: "fixed", inset: 0, zIndex: 1000, display: "flex", alignItems: "center", justifyContent: "center", padding: 16, background: "rgba(0,0,0,0.42)" }}
+          onClick={(event) => {
+            if (event.target === event.currentTarget && !projectRemovalBusy) setProjectPendingRemoval(null);
+          }}
+        >
+          <div style={{ width: 380, maxWidth: "100%", padding: 18, border: "1px solid var(--border)", borderRadius: 8, background: "var(--bg)", boxShadow: "0 16px 48px rgba(0,0,0,0.28)" }}>
+            <h2 id="remove-project-title" style={{ margin: 0, color: "var(--text)", fontSize: 15, lineHeight: 1.4 }}>
+              {t("sidebar.removeProjectTitle", { name: projectName(projectPendingRemoval) })}
+            </h2>
+            <p style={{ margin: "8px 0 0", color: "var(--text-muted)", fontSize: 12, lineHeight: 1.6 }}>
+              {t("sidebar.removeProjectDescription", { count: allSessions.filter((session) => (session.projectRoot ?? session.cwd) === projectPendingRemoval).length })}
+            </p>
+            {projectRemovalError && (
+              <p role="alert" style={{ margin: "8px 0 0", color: "#ef4444", fontSize: 11, overflowWrap: "anywhere" }}>{projectRemovalError}</p>
+            )}
+            <div style={{ display: "flex", justifyContent: "flex-end", gap: 8, marginTop: 16 }}>
+              <button type="button" disabled={projectRemovalBusy} onClick={() => setProjectPendingRemoval(null)} style={{ height: 32, padding: "0 12px", border: "1px solid var(--border)", borderRadius: 6, background: "var(--bg-hover)", color: "var(--text-muted)", cursor: projectRemovalBusy ? "default" : "pointer" }}>
+                {t("sidebar.cancel")}
+              </button>
+              <button type="button" disabled={projectRemovalBusy} onClick={() => void handleRemoveProject()} style={{ height: 32, padding: "0 12px", border: 0, borderRadius: 6, background: "#dc2626", color: "#fff", fontWeight: 600, cursor: projectRemovalBusy ? "default" : "pointer", opacity: projectRemovalBusy ? 0.65 : 1 }}>
+                {projectRemovalBusy ? t("sidebar.removingProject") : t("sidebar.removeProject")}
+              </button>
+            </div>
+          </div>
+        </div>
+      )}
       {/* Header */}
       <div
         style={{
@@ -884,17 +961,16 @@ export function SessionSidebar({ selectedSessionId, onSelectSession, onNewSessio
           <PiWebTitle />
           <div style={{ display: "flex", gap: 6 }}>
             <button
-              onClick={handleNewSession}
-              disabled={!selectedCwd}
+              onClick={handleCustomPathClick}
               style={{
                 display: "flex", alignItems: "center", justifyContent: "center", gap: 5,
                 background: "var(--bg-hover)",
                 border: "1px solid var(--border)",
-                color: selectedCwd ? "var(--text-muted)" : "var(--text-dim)",
-                cursor: selectedCwd ? "pointer" : "not-allowed",
+                color: "var(--text-muted)",
+                cursor: "pointer",
+                width: 32,
                 height: 32,
-                paddingLeft: 10,
-                paddingRight: 12,
+                padding: 0,
                 borderRadius: 7,
                 fontSize: 12,
                 fontWeight: 500,
@@ -902,16 +978,16 @@ export function SessionSidebar({ selectedSessionId, onSelectSession, onNewSessio
                 flexShrink: 0,
                 transition: "background 0.12s, color 0.12s, border-color 0.12s",
               }}
-             title={selectedCwd ? t("sidebar.newSessionTitle", { path: selectedCwd }) : t("sidebar.selectProject")}
+              title={t("sidebar.customPath")}
+              aria-label={t("sidebar.customPath")}
               onMouseEnter={(e) => {
-                if (!selectedCwd) return;
                 e.currentTarget.style.background = "var(--bg-selected)";
                 e.currentTarget.style.color = "var(--accent)";
                 e.currentTarget.style.borderColor = "rgba(37,99,235,0.35)";
               }}
               onMouseLeave={(e) => {
                 e.currentTarget.style.background = "var(--bg-hover)";
-                e.currentTarget.style.color = selectedCwd ? "var(--text-muted)" : "var(--text-dim)";
+                e.currentTarget.style.color = "var(--text-muted)";
                 e.currentTarget.style.borderColor = "var(--border)";
               }}
             >
@@ -919,7 +995,6 @@ export function SessionSidebar({ selectedSessionId, onSelectSession, onNewSessio
                 <line x1="6" y1="1" x2="6" y2="11" />
                 <line x1="1" y1="6" x2="11" y2="6" />
               </svg>
-              {t("sidebar.new")}
             </button>
             <button
               onClick={() => loadSessions(false)}
@@ -963,197 +1038,6 @@ export function SessionSidebar({ selectedSessionId, onSelectSession, onNewSessio
           </div>
         </div>
 
-        {/* CWD picker */}
-        <div ref={dropdownRef} style={{ position: "relative" }}>
-          <button
-            onClick={() => setDropdownOpen((v) => !v)}
-            title={selectedProject ?? selectedCwd ?? ""}
-            style={{
-              width: "100%",
-              display: "flex",
-              alignItems: "center",
-              padding: "6px 10px",
-              background: selectedCwd ? "var(--bg-hover)" : "rgba(37,99,235,0.06)",
-              border: selectedCwd ? "1px solid var(--border)" : "1px solid rgba(37,99,235,0.4)",
-              borderRadius: 7,
-              cursor: "pointer",
-              fontSize: 12,
-              color: "var(--text)",
-              textAlign: "left",
-              transition: "border-color 0.15s, background 0.15s",
-            }}
-          >
-            {selectedCwd ? (
-              <PathLabel
-                text={displayCwd(selectedProject ?? selectedCwd, homeDir)}
-                style={{
-                  flex: 1,
-                  fontFamily: "var(--font-mono)",
-                  fontSize: 11,
-                  color: "var(--text)",
-                }}
-              />
-            ) : (
-              <span
-                style={{
-                  flex: 1,
-                  overflow: "hidden",
-                  textOverflow: "ellipsis",
-                  whiteSpace: "nowrap",
-                  fontFamily: "var(--font-mono)",
-                  fontSize: 11,
-                  color: "var(--text-dim)",
-                }}
-              >
-                 {initialSessionId && !restoredRef.current ? "" : t("sidebar.selectProject")}
-              </span>
-            )}
-          </button>
-
-          <AnimatedDropdown
-            open={dropdownOpen}
-            style={{
-              position: "absolute",
-              top: "calc(100% + 4px)",
-              left: 0,
-              right: 0,
-              zIndex: 100,
-              background: "var(--bg)",
-              border: "1px solid var(--border)",
-              borderRadius: 8,
-              boxShadow: "0 6px 20px rgba(0,0,0,0.10)",
-              overflow: "hidden",
-            }}
-          >
-              {showProjectFilter && (
-                <div style={{ padding: "6px 8px", borderBottom: "1px solid var(--border)" }}>
-                  <input
-                    value={projectFilter}
-                    onChange={(e) => setProjectFilter(e.target.value)}
-                    onKeyDown={(e) => {
-                      if (e.key === "Escape") {
-                        setProjectFilter("");
-                        setDropdownOpen(false);
-                      }
-                    }}
-                     placeholder={t("sidebar.filterProjects")}
-                    autoFocus
-                    style={{
-                      width: "100%",
-                      fontSize: 11,
-                      fontFamily: "var(--font-mono)",
-                      padding: "5px 8px",
-                      border: "1px solid var(--border)",
-                      borderRadius: 5,
-                      outline: "none",
-                      background: "var(--bg)",
-                      color: "var(--text)",
-                      boxSizing: "border-box",
-                    }}
-                  />
-                </div>
-              )}
-              <div style={{ maxHeight: "min(50vh, 380px)", overflowY: "auto" }}>
-                {visibleProjects.map((project) => (
-                  <button
-                    key={project}
-                    onClick={() => {
-                      setSelectedCwd(project);
-                      setProjectFilter("");
-                      setCustomPathOpen(false);
-                      setCustomPathValue("");
-                      setCustomPathError(null);
-                      setDropdownOpen(false);
-                    }}
-                    style={{
-                      display: "flex",
-                      alignItems: "center",
-                      gap: 7,
-                      width: "100%",
-                      padding: "8px 10px",
-                      background: "var(--bg)",
-                      border: "none",
-                      borderBottom: "1px solid var(--border)",
-                      color: project === selectedProject ? "var(--text)" : "var(--text-muted)",
-                      cursor: "pointer",
-                      textAlign: "left",
-                      fontSize: 11,
-                      fontFamily: "var(--font-mono)",
-                      overflow: "hidden",
-                      textOverflow: "ellipsis",
-                      whiteSpace: "nowrap",
-                    }}
-                    title={project}
-                  >
-                    {project === selectedProject && (
-                      <svg width="10" height="10" viewBox="0 0 10 10" fill="none" stroke="var(--accent)" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round" style={{ flexShrink: 0 }}>
-                        <polyline points="1.5 5 4 7.5 8.5 2.5" />
-                      </svg>
-                    )}
-                    {project !== selectedProject && <span style={{ width: 10, flexShrink: 0 }} />}
-                    <PathLabel text={displayCwd(project, homeDir)} style={{ flex: 1 }} />
-                  </button>
-                ))}
-                {visibleProjects.length === 0 && projectFilter.trim() && (
-                   <div style={{ padding: "8px 10px", fontSize: 11, color: "var(--text-dim)" }}>{t("sidebar.noMatchingProjects")}</div>
-                )}
-              </div>
-
-              {/* Default cwd shortcut */}
-              {!customPathOpen && (
-                <button
-                  onClick={(e) => { e.stopPropagation(); handleDefaultCwd(); }}
-                  style={{
-                    display: "flex",
-                    alignItems: "center",
-                    gap: 7,
-                    width: "100%",
-                    padding: "8px 10px",
-                    background: "none",
-                    border: "none",
-                    borderTop: visibleProjects.length > 0 ? "1px solid var(--border)" : "none",
-                    color: "var(--text-muted)",
-                    cursor: "pointer",
-                    textAlign: "left",
-                    fontSize: 11,
-                  }}
-                >
-                  <svg width="10" height="10" viewBox="0 0 10 10" fill="none" stroke="currentColor" strokeWidth="1.1" strokeLinecap="round" strokeLinejoin="round" style={{ flexShrink: 0 }}>
-                    <path d="M1 3A1 1 0 0 1 2 2H4L5 3.5H8.5a.5.5 0 0 1 .5.5v4a.5.5 0 0 1-.5.5h-7A.5.5 0 0 1 1 8V3Z" />
-                  </svg>
-                   <span>{t("sidebar.useDefaultDirectory")}</span>
-                </button>
-              )}
-
-              {/* Custom path directory picker */}
-              <button
-                onClick={(e) => {
-                  e.stopPropagation();
-                  handleCustomPathClick();
-                }}
-                style={{
-                  display: "flex",
-                  alignItems: "center",
-                  gap: 7,
-                  width: "100%",
-                  padding: "8px 10px",
-                  background: "none",
-                  border: "none",
-                  color: "var(--text-muted)",
-                  cursor: "pointer",
-                  textAlign: "left",
-                  fontSize: 11,
-                }}
-              >
-                <svg width="10" height="10" viewBox="0 0 10 10" fill="none" stroke="currentColor" strokeWidth="1.1" strokeLinecap="round" style={{ flexShrink: 0 }}>
-                  <line x1="5" y1="1" x2="5" y2="9" />
-                  <line x1="1" y1="5" x2="9" y2="5" />
-                </svg>
-                <span>{t("sidebar.customPath")}</span>
-              </button>
-          </AnimatedDropdown>
-        </div>
-
         {/* Worktree switcher — shown only for git projects at a checkout top
             level (repo subdirs keep their own project identity, so switching
             from them would jump projects). Rendered whenever the selected cwd
@@ -1161,7 +1045,7 @@ export function SessionSidebar({ selectedSessionId, onSelectSession, onNewSessio
             switching between worktrees of one project keeps the row mounted
             instead of flickering while data refetches: all worktrees of a
             project share the same list anyway. */}
-        {showWorktreeSwitcher && (() => {
+        {showWorktreeSwitcher && worktreeState && worktreeState.worktrees.length > 1 && (() => {
           if (!worktreeState) return null;
           const currentWt = worktreeState.worktrees.find((w) => w.path === selectedCwd)
             ?? worktreeState.worktrees.find((w) => w.isMain);
@@ -1476,7 +1360,7 @@ export function SessionSidebar({ selectedSessionId, onSelectSession, onNewSessio
             type="button"
             aria-disabled="true"
             tabIndex={-1}
-            title={inactiveWorktreeSelector.title}
+            title={inactiveWorktreeSelector?.title ?? ""}
             style={{
               width: "100%",
               height: 29,
@@ -1504,12 +1388,12 @@ export function SessionSidebar({ selectedSessionId, onSelectSession, onNewSessio
               <circle cx="6" cy="18" r="3" />
               <path d="M18 9a9 9 0 0 1-9 9" />
             </svg>
-            <span style={{ overflow: "hidden", textOverflow: "ellipsis" }}>{inactiveWorktreeSelector.label}</span>
+            <span style={{ overflow: "hidden", textOverflow: "ellipsis" }}>{inactiveWorktreeSelector?.label}</span>
           </button>
         )}
       </div>
 
-      {/* Session list */}
+      {/* 项目目录与会话组成同一棵导航树，减少在目录选择器和会话列表之间切换。 */}
       <div style={{ flex: explorerOpen && (selectedCwdProp || selectedCwd) ? "1 1 0" : "1 1 auto", overflowY: "auto", padding: "0", minHeight: 80 }}>
         {loading && (
           <div style={{ padding: "16px 14px", color: "var(--text-muted)", fontSize: 12 }}>
@@ -1521,27 +1405,146 @@ export function SessionSidebar({ selectedSessionId, onSelectSession, onNewSessio
             {error}
           </div>
         )}
-        {!loading && !error && filteredSessions.length === 0 && (
+        {!loading && !error && visibleProjects.length === 0 && (
           <div style={{ padding: "16px 14px", color: "var(--text-muted)", fontSize: 12 }}>
-            {t("sidebar.noSessions")}
+            {t("sidebar.selectProject")}
           </div>
         )}
-        {sessionTree.map((node) => (
-          <SessionTreeItem
-            key={node.session.id}
-            node={node}
-            selectedSessionId={selectedSessionId}
-            runningSessionIds={runningSessionIds}
-            unreadSessionIds={unreadSessionIds}
-            onSelectSession={handleSelectSessionFromList}
-            onRenamed={loadSessions}
-            onSessionDeleted={(id) => {
-              onSessionDeleted?.(id);
-              loadSessions();
-            }}
-            depth={0}
-          />
-        ))}
+        {visibleProjects.map((project) => {
+          const collapsed = collapsedProjects.has(project);
+          const projectSessions = visibleSessions.filter((session) => displayProject(session) === project);
+          const projectTree = buildSessionTree(projectSessions);
+          const active = project === selectedDisplayProject;
+          return (
+            <section key={project} style={{ padding: "2px 6px 6px" }}>
+              <div
+                style={{
+                  display: "flex",
+                  alignItems: "center",
+                  minHeight: 34,
+                  borderRadius: 6,
+                  background: active ? "var(--bg-hover)" : "transparent",
+                }}
+              >
+                <button
+                  type="button"
+                  onClick={() => {
+                    void commitCustomPath(project);
+                    setCollapsedProjects((current) => {
+                      const next = new Set(current);
+                      if (next.has(project)) next.delete(project);
+                      else next.add(project);
+                      return next;
+                    });
+                  }}
+                  title={project}
+                  aria-expanded={!collapsed}
+                  style={{
+                    display: "flex",
+                    alignItems: "center",
+                    gap: 7,
+                    flex: 1,
+                    minWidth: 0,
+                    height: 34,
+                    padding: "0 4px 0 7px",
+                    border: 0,
+                    background: "transparent",
+                    color: active ? "var(--text)" : "var(--text-muted)",
+                    cursor: "pointer",
+                    textAlign: "left",
+                  }}
+                >
+                  <svg width="9" height="9" viewBox="0 0 10 10" fill="none" stroke="currentColor" strokeWidth="1.7" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true" style={{ transform: collapsed ? "none" : "rotate(90deg)", transition: "transform 0.12s", flexShrink: 0 }}>
+                    <polyline points="3 2 7 5 3 8" />
+                  </svg>
+                  <svg width="16" height="16" viewBox="0 0 20 20" fill="none" stroke="currentColor" strokeWidth="1.5" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true" style={{ flexShrink: 0 }}>
+                    <path d="M2.5 5.5h5l1.7 2h8.3v7.5a1.5 1.5 0 0 1-1.5 1.5H4A1.5 1.5 0 0 1 2.5 15V5.5Z" />
+                  </svg>
+                  <span style={{ overflow: "hidden", textOverflow: "ellipsis", whiteSpace: "nowrap", fontSize: 13, fontWeight: 600 }}>
+                    {projectName(project)}
+                  </span>
+                </button>
+                <button
+                  type="button"
+                  onClick={() => {
+                    setProjectRemovalError(null);
+                    setProjectPendingRemoval(project);
+                  }}
+                  title={t("sidebar.removeProjectButton", { name: projectName(project) })}
+                  aria-label={t("sidebar.removeProjectButton", { name: projectName(project) })}
+                  style={{ width: 28, height: 28, padding: 0, display: "flex", alignItems: "center", justifyContent: "center", border: 0, borderRadius: 5, background: "transparent", color: "var(--text-dim)", cursor: "pointer", flexShrink: 0 }}
+                >
+                  <svg width="12" height="12" viewBox="0 0 12 12" fill="none" stroke="currentColor" strokeWidth="1.8" strokeLinecap="round" aria-hidden="true">
+                    <line x1="2" y1="6" x2="10" y2="6" />
+                  </svg>
+                </button>
+                <button
+                  type="button"
+                  onClick={() => handleNewSession(project)}
+                  title={t("sidebar.newSessionTitle", { path: project })}
+                  aria-label={t("sidebar.newSessionTitle", { path: project })}
+                  style={{ width: 28, height: 28, padding: 0, marginRight: 3, display: "flex", alignItems: "center", justifyContent: "center", border: 0, borderRadius: 5, background: "transparent", color: "var(--text-dim)", cursor: "pointer", flexShrink: 0 }}
+                >
+                  <svg width="12" height="12" viewBox="0 0 12 12" fill="none" stroke="currentColor" strokeWidth="1.8" strokeLinecap="round" aria-hidden="true">
+                    <line x1="6" y1="1" x2="6" y2="11" />
+                    <line x1="1" y1="6" x2="11" y2="6" />
+                  </svg>
+                </button>
+              </div>
+              {active && !collapsed && showWorktreeSwitcher && worktreeState && (() => {
+                const currentWorktree = worktreeState.worktrees.find((worktree) => worktree.path === selectedCwd)
+                  ?? worktreeState.worktrees.find((worktree) => worktree.isMain);
+                return (
+                  <label
+                    title={currentWorktree?.path}
+                    style={{ display: "flex", alignItems: "center", gap: 6, height: 28, margin: "0 6px 2px 30px", color: "var(--text-dim)" }}
+                  >
+                    <svg width="11" height="11" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true" style={{ flexShrink: 0 }}>
+                      <line x1="6" y1="3" x2="6" y2="15" />
+                      <circle cx="18" cy="6" r="3" />
+                      <circle cx="6" cy="18" r="3" />
+                      <path d="M18 9a9 9 0 0 1-9 9" />
+                    </svg>
+                    <select
+                      aria-label={t("sidebar.switchWorktree")}
+                      value={currentWorktree?.path ?? ""}
+                      onChange={(event) => setSelectedCwd(event.target.value)}
+                      style={{ minWidth: 0, flex: 1, height: 26, padding: "0 24px 0 0", border: 0, outline: 0, background: "transparent", color: "var(--text-muted)", fontFamily: "var(--font-mono)", fontSize: 11, cursor: "pointer" }}
+                    >
+                      {worktreeState.worktrees.map((worktree) => (
+                        <option key={worktree.path} value={worktree.path}>
+                          {worktree.branch ?? projectName(worktree.path)}{worktree.isMain ? ` · ${t("sidebar.main")}` : ""}
+                        </option>
+                      ))}
+                    </select>
+                  </label>
+                );
+              })()}
+              {!collapsed && (
+                <div style={{ paddingLeft: 24 }}>
+                  {projectTree.length === 0 ? (
+                    <div style={{ padding: "5px 10px 7px", color: "var(--text-dim)", fontSize: 11 }}>{t("sidebar.noSessions")}</div>
+                  ) : projectTree.map((node) => (
+                    <SessionTreeItem
+                      key={node.session.id}
+                      node={node}
+                      selectedSessionId={selectedSessionId}
+                      runningSessionIds={runningSessionIds}
+                      unreadSessionIds={unreadSessionIds}
+                      onSelectSession={handleSelectSessionFromList}
+                      onRenamed={loadSessions}
+                      onSessionDeleted={(id) => {
+                        onSessionDeleted?.(id);
+                        loadSessions();
+                      }}
+                      depth={0}
+                    />
+                  ))}
+                </div>
+              )}
+            </section>
+          );
+        })}
       </div>
 
       {/* File Explorer section */}
diff --git a/hooks/useAgentSession.ts b/hooks/useAgentSession.ts
index 3b0dd7ed..d7664583 100644
--- a/hooks/useAgentSession.ts
+++ b/hooks/useAgentSession.ts
@@ -161,9 +161,10 @@ const PROMPT_SETTLE_POLL_MS = 600;
 const PROMPT_SETTLE_MAX_MS = 20_000;
 const AGENT_STATE_RECONCILE_MS = 15_000;
 const BASH_STATE_RECONCILE_MS = 1_000;
-const EVENT_STREAM_CONNECT_TIMEOUT_MS = 5_000;
+// AgentSession 冷启动可能包含模型、扩展和资源初始化，5 秒不足以覆盖正常启动耗时。
+const EVENT_STREAM_CONNECT_TIMEOUT_MS = 15_000;
 const MAX_NOTICES = 5;
-const NOTICE_VISIBLE_MS = 5000;
+const NOTICE_VISIBLE_MS = 2500;
 const NOTICE_EXIT_ANIMATION_MS = 180;
 const SCROLL_KEYS = new Set(["ArrowUp", "ArrowDown", "PageUp", "PageDown", "Home", "End", " ", "Space", "Spacebar"]);
 
@@ -380,6 +381,7 @@ export function useAgentSession(opts: UseAgentSessionOptions) {
   const initialScrollDoneRef = useRef(false);
   const lastUserMsgRef = useRef<HTMLDivElement | null>(null);
   const pendingScrollToUserRef = useRef(false);
+  const pendingScrollToRunningEndRef = useRef(false);
   const completionScrollAllowedRef = useRef(true);
   const executeBashRef = useRef<(command: string, excludeFromContext: boolean) => Promise<void> | undefined>(undefined);
   const userScrollIntentUntilRef = useRef(0);
@@ -719,6 +721,10 @@ export function useAgentSession(opts: UseAgentSessionOptions) {
     });
   }, []);
 
+  const dismissNotice = useCallback((id: string) => {
+    dispatchNotice({ type: "remove", id });
+  }, []);
+
   const handleExtensionUiRequest = useCallback((request: ExtensionUiRequest) => {
     switch (request.method) {
       case "select":
@@ -1523,7 +1529,7 @@ export function useAgentSession(opts: UseAgentSessionOptions) {
 
   const scrollToBottom = useCallback((behavior: ScrollBehavior = "smooth") => {
     ignoreProgrammaticScrollUntilRef.current = Date.now() + PROGRAMMATIC_SCROLL_IGNORE_MS;
-    messagesEndRef.current?.scrollIntoView({ behavior });
+    messagesEndRef.current?.scrollIntoView({ behavior, block: "end" });
   }, []);
 
   const scrollUserMsgToTop = useCallback(() => {
@@ -1558,6 +1564,7 @@ export function useAgentSession(opts: UseAgentSessionOptions) {
         if (agentState?.running) {
           loadTools(session.id);
           if (agentState.state?.isStreaming || agentState.state?.isPromptRunning) {
+            pendingScrollToRunningEndRef.current = true;
             agentRunningRef.current = true;
             setAgentRunning(true);
             setAgentPhase(agentState.state.isStreaming ? { kind: "waiting_model" } : { kind: "running_command" });
@@ -1628,6 +1635,10 @@ export function useAgentSession(opts: UseAgentSessionOptions) {
         pendingScrollToUserRef.current = false;
         initialScrollDoneRef.current = true;
         scrollUserMsgToTop();
+      } else if (pendingScrollToRunningEndRef.current) {
+        pendingScrollToRunningEndRef.current = false;
+        initialScrollDoneRef.current = true;
+        scrollToBottom("instant");
       } else if (!initialScrollDoneRef.current) {
         initialScrollDoneRef.current = true;
         scrollToBottom("instant");
@@ -1680,7 +1691,7 @@ export function useAgentSession(opts: UseAgentSessionOptions) {
     retryInfo, contextUsage, systemPrompt, forkingEntryId,
     isCompacting, compactError, compactResult, currentModel, displayModel, sessionStats,
     slashCommands, slashCommandsLoading, queuedMessages,
-    notices: noticeState.visible, extensionDialog, extensionCustomUi, extensionStatuses, extensionWidgets, respondToExtensionUi, sendExtensionCustomInput,
+    notices: noticeState.visible, dismissNotice, extensionDialog, extensionCustomUi, extensionStatuses, extensionWidgets, respondToExtensionUi, sendExtensionCustomInput,
     isAutoModelSelection: isNew && newSessionModel === null,
     agentPhase,
     isNew,
diff --git a/hooks/useCompletionNotification.test.mjs b/hooks/useCompletionNotification.test.mjs
new file mode 100644
index 00000000..b36d10df
--- /dev/null
+++ b/hooks/useCompletionNotification.test.mjs
@@ -0,0 +1,37 @@
+import assert from "node:assert/strict";
+import { readFile } from "node:fs/promises";
+import test from "node:test";
+
+const hookSource = await readFile(new URL("./useCompletionNotification.ts", import.meta.url), "utf8");
+const serviceWorkerSource = await readFile(new URL("../public/sw.js", import.meta.url), "utf8");
+
+test("requests permission only from the explicit notification toggle", () => {
+  assert.match(hookSource, /const toggle = useCallback\(async \(\) =>/);
+  assert.match(hookSource, /await Notification\.requestPermission\(\)/);
+  assert.ok(
+    hookSource.indexOf("Notification.requestPermission()") > hookSource.indexOf("const toggle = useCallback"),
+  );
+});
+
+test("shows the first-visit prompt only while permission is undecided", () => {
+  assert.match(hookSource, /getPermission\(\) === "default"/);
+  assert.match(hookSource, /PROMPT_DISMISSED_KEY/);
+});
+
+test("service worker notification click returns to the target session", () => {
+  assert.match(serviceWorkerSource, /notificationclick/);
+  assert.match(serviceWorkerSource, /client\.navigate\(targetUrl\)/);
+  assert.match(serviceWorkerSource, /self\.clients\.openWindow\(targetUrl\)/);
+});
+
+test("completion notifications are also sent while the app is focused", () => {
+  assert.doesNotMatch(hookSource, /document\.visibilityState/);
+  assert.doesNotMatch(hookSource, /document\.hasFocus/);
+  assert.match(hookSource, /registration\.showNotification\(title, options\)/);
+  assert.match(hookSource, /new Notification\(title, options\)/);
+});
+
+test("exposes a session notification sender for completion and input requests", () => {
+  assert.match(hookSource, /const notifySession = useCallback/);
+  assert.match(hookSource, /notifySession,/);
+});
diff --git a/hooks/useCompletionNotification.ts b/hooks/useCompletionNotification.ts
new file mode 100644
index 00000000..d7888ce6
--- /dev/null
+++ b/hooks/useCompletionNotification.ts
@@ -0,0 +1,102 @@
+"use client";
+
+import { useCallback, useEffect, useRef, useState } from "react";
+
+const STORAGE_KEY = "pi-notification-enabled";
+const PROMPT_DISMISSED_KEY = "pi-notification-prompt-dismissed";
+
+type CompletionNotificationPermission = NotificationPermission | "unsupported";
+
+function getPermission(): CompletionNotificationPermission {
+  if (typeof window === "undefined" || !("Notification" in window)) return "unsupported";
+  return Notification.permission;
+}
+
+export function useCompletionNotification() {
+  const [permission, setPermission] = useState<CompletionNotificationPermission>(getPermission);
+  const [enabled, setEnabled] = useState(() => (
+    typeof window !== "undefined"
+    && localStorage.getItem(STORAGE_KEY) === "true"
+    && getPermission() === "granted"
+  ));
+  const [showPrompt, setShowPrompt] = useState(() => (
+    typeof window !== "undefined"
+    && getPermission() === "default"
+    && localStorage.getItem(PROMPT_DISMISSED_KEY) !== "true"
+  ));
+  const enabledRef = useRef(enabled);
+
+  useEffect(() => {
+    enabledRef.current = enabled;
+  }, [enabled]);
+
+  const toggle = useCallback(async () => {
+    if (!("Notification" in window)) return;
+
+    localStorage.setItem(PROMPT_DISMISSED_KEY, "true");
+    setShowPrompt(false);
+
+    if (enabledRef.current) {
+      enabledRef.current = false;
+      localStorage.setItem(STORAGE_KEY, "false");
+      setEnabled(false);
+      setPermission(Notification.permission);
+      return;
+    }
+
+    const nextPermission = Notification.permission === "granted"
+      ? "granted"
+      : await Notification.requestPermission();
+    setPermission(nextPermission);
+    const nextEnabled = nextPermission === "granted";
+    enabledRef.current = nextEnabled;
+    localStorage.setItem(STORAGE_KEY, String(nextEnabled));
+    setEnabled(nextEnabled);
+  }, []);
+
+  const dismissPrompt = useCallback(() => {
+    localStorage.setItem(PROMPT_DISMISSED_KEY, "true");
+    setShowPrompt(false);
+  }, []);
+
+  const notifySession = useCallback(async (title: string, body: string, sessionId?: string | null) => {
+    if (!enabledRef.current || Notification.permission !== "granted") return;
+
+    const url = sessionId ? `/?session=${encodeURIComponent(sessionId)}` : "/";
+    const options: NotificationOptions = {
+      body,
+      icon: "/icons/icon-192.png",
+      badge: "/icons/icon-192.png",
+      tag: sessionId ? `pi-session-${sessionId}` : "pi-session-complete",
+      data: { url },
+    };
+
+    try {
+      const registration = "serviceWorker" in navigator
+        ? await navigator.serviceWorker.getRegistration()
+        : undefined;
+      if (registration) {
+        await registration.showNotification(title, options);
+        return;
+      }
+
+      const notification = new Notification(title, options);
+      notification.onclick = () => {
+        window.focus();
+        window.location.assign(url);
+        notification.close();
+      };
+    } catch (error) {
+      console.error("任务完成通知发送失败", error);
+    }
+  }, []);
+
+  return {
+    notificationEnabled: enabled,
+    notificationPermission: permission,
+    showNotificationPrompt: showPrompt,
+    onNotificationToggle: toggle,
+    dismissNotificationPrompt: dismissPrompt,
+    notifySession,
+  };
+}
diff --git a/lib/file-fuzzy.ts b/lib/file-fuzzy.ts
index 75ad7cc0..a0bb5a2b 100644
--- a/lib/file-fuzzy.ts
+++ b/lib/file-fuzzy.ts
@@ -24,18 +24,20 @@ export interface FileIndexEntry {
  * @"my dir/fi so drill-down into space-containing paths keeps working.
  */
 export function extractAtQuery(textBeforeCursor: string): AtQueryMatch | null {
-  const quoted = /(?:^|\s)@"([^"\n]*)$/.exec(textBeforeCursor);
+  const lineStart = textBeforeCursor.lastIndexOf("\n") + 1;
+  const line = textBeforeCursor.slice(lineStart);
+  const quoted = /(?:^|\s)@"([^"\n]*)$/.exec(line);
   if (quoted) {
     return {
-      start: textBeforeCursor.length - (quoted[1].length + 2),
+      start: lineStart + line.length - (quoted[1].length + 2),
       query: quoted[1],
       quoted: true,
     };
   }
-  const plain = /(?:^|\s)@([^\s"]*)$/.exec(textBeforeCursor);
+  const plain = /(?:^|\s)@([^\s"]*)$/.exec(line);
   if (plain) {
     return {
-      start: textBeforeCursor.length - (plain[1].length + 1),
+      start: lineStart + line.length - (plain[1].length + 1),
       query: plain[1],
       quoted: false,
     };
diff --git a/lib/i18n/messages/en.ts b/lib/i18n/messages/en.ts
index a5dedf8f..578d9765 100644
--- a/lib/i18n/messages/en.ts
+++ b/lib/i18n/messages/en.ts
@@ -119,6 +119,11 @@ export const enLocale: LocalePlugin = {
     "sidebar.rename": "Rename",
     "sidebar.delete": "Delete",
     "sidebar.deleteWithShiftClick": "Delete (Shift+click to delete without confirmation)",
+    "sidebar.removeProjectButton": "Remove {name}",
+    "sidebar.removeProjectTitle": "Remove {name}?",
+    "sidebar.removeProjectDescription": "This removes the directory from the sidebar and permanently deletes its {count} sessions. Files in the directory are not deleted.",
+    "sidebar.removeProject": "Remove and delete sessions",
+    "sidebar.removingProject": "Removing…",
     "sidebar.expandForks": "Expand forks",
     "sidebar.collapseForks": "Collapse forks",
     "sidebar.messagesCount": "{count} msgs",
@@ -220,6 +225,16 @@ export const enLocale: LocalePlugin = {
     "chat.stop": "Stop",
     "chat.disableSound": "Disable completion sound",
     "chat.enableSound": "Enable completion sound",
+    "chat.disableNotification": "Disable completion notifications",
+    "chat.enableNotification": "Enable completion notifications",
+    "chat.notificationBlocked": "Notifications are blocked; allow them in site settings",
+    "chat.notificationPromptTitle": "Enable completion notifications",
+    "chat.notificationPromptBody": "Get a system notification when the AI finishes",
+    "chat.notificationPromptLater": "Not now",
+    "chat.notificationPromptEnable": "Enable",
+    "chat.notificationDoneBody": "The AI response is ready",
+    "chat.notificationAttentionTitle": "AI is waiting for input",
+    "chat.notificationAttentionBody": "The AI is waiting for your response",
     "chat.thinkingUseDefault": "Use pi default",
     "chat.thinkingOff": "Reasoning off",
     "chat.thinkingMinimal": "Minimal reasoning",
@@ -407,6 +422,9 @@ export const enLocale: LocalePlugin = {
     "i18n.thinking": "Thinking",
     "i18n.loadingThinking": "Loading thinking...",
     "i18n.copyMessage": "Copy message",
+    "chat.longMessageStats": "{characters} characters · {lines} lines",
+    "chat.viewLongMessage": "View",
+    "chat.collapseLongMessage": "Collapse",
     "i18n.editFromHere": "Edit from here",
     "i18n.editFromHereTitle": "Edit from here — branches within this session",
     "i18n.newSession": "New session",
diff --git a/lib/i18n/messages/zh-CN.ts b/lib/i18n/messages/zh-CN.ts
index 878d9603..1b7c1bce 100644
--- a/lib/i18n/messages/zh-CN.ts
+++ b/lib/i18n/messages/zh-CN.ts
@@ -119,6 +119,11 @@ export const zhCNLocale: LocalePlugin = {
     "sidebar.rename": "重命名",
     "sidebar.delete": "删除",
     "sidebar.deleteWithShiftClick": "删除（按住 Shift 点击可跳过确认）",
+    "sidebar.removeProjectButton": "移除 {name}",
+    "sidebar.removeProjectTitle": "移除 {name}？",
+    "sidebar.removeProjectDescription": "将从侧边栏移除此目录，并永久删除所属的 {count} 个会话。目录中的文件不会被删除。",
+    "sidebar.removeProject": "移除并删除会话",
+    "sidebar.removingProject": "正在移除…",
     "sidebar.expandForks": "展开分叉",
     "sidebar.collapseForks": "折叠分叉",
     "sidebar.messagesCount": "{count} 条消息",
@@ -220,6 +225,16 @@ export const zhCNLocale: LocalePlugin = {
     "chat.stop": "停止",
     "chat.disableSound": "关闭完成提示音",
     "chat.enableSound": "开启完成提示音",
+    "chat.disableNotification": "关闭完成通知",
+    "chat.enableNotification": "开启完成通知",
+    "chat.notificationBlocked": "系统通知已被阻止，请在站点设置中允许",
+    "chat.notificationPromptTitle": "开启任务完成通知",
+    "chat.notificationPromptBody": "AI 回复完成后发送系统通知",
+    "chat.notificationPromptLater": "暂不开启",
+    "chat.notificationPromptEnable": "开启",
+    "chat.notificationDoneBody": "AI 回复已完成",
+    "chat.notificationAttentionTitle": "AI 正在等待输入",
+    "chat.notificationAttentionBody": "AI 正在等待你的回复",
     "chat.thinkingUseDefault": "使用 pi 默认设置",
     "chat.thinkingOff": "关闭推理",
     "chat.thinkingMinimal": "最低限度推理",
@@ -407,6 +422,9 @@ export const zhCNLocale: LocalePlugin = {
     "i18n.thinking": "思考",
     "i18n.loadingThinking": "正在加载思考内容...",
     "i18n.copyMessage": "复制消息",
+    "chat.longMessageStats": "{characters} 字符 · {lines} 行",
+    "chat.viewLongMessage": "查看全文",
+    "chat.collapseLongMessage": "收起",
     "i18n.editFromHere": "从此处编辑",
     "i18n.editFromHereTitle": "从此处编辑，此会话内创建分支",
     "i18n.newSession": "新会话",
diff --git a/lib/long-user-message.test.mjs b/lib/long-user-message.test.mjs
new file mode 100644
index 00000000..bd4bf7ea
--- /dev/null
+++ b/lib/long-user-message.test.mjs
@@ -0,0 +1,25 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+import { createJiti } from "jiti";
+
+const jiti = createJiti(import.meta.url);
+const {
+  LONG_USER_MESSAGE_CHAR_LIMIT,
+  LONG_USER_MESSAGE_LINE_LIMIT,
+  getLongUserMessageStats,
+} = await jiti.import("./long-user-message.ts");
+
+test("字符数超过阈值时折叠长消息", () => {
+  assert.equal(getLongUserMessageStats("x".repeat(LONG_USER_MESSAGE_CHAR_LIMIT)).compact, false);
+  assert.equal(getLongUserMessageStats("x".repeat(LONG_USER_MESSAGE_CHAR_LIMIT + 1)).compact, true);
+});
+
+test("行数超过阈值时折叠长消息", () => {
+  const atLimit = Array.from({ length: LONG_USER_MESSAGE_LINE_LIMIT }, () => "x").join("\n");
+  assert.deepEqual(getLongUserMessageStats(atLimit), {
+    characters: atLimit.length,
+    lines: LONG_USER_MESSAGE_LINE_LIMIT,
+    compact: false,
+  });
+  assert.equal(getLongUserMessageStats(`${atLimit}\nx`).compact, true);
+});
diff --git a/lib/long-user-message.ts b/lib/long-user-message.ts
new file mode 100644
index 00000000..5dd393b1
--- /dev/null
+++ b/lib/long-user-message.ts
@@ -0,0 +1,21 @@
+export const LONG_USER_MESSAGE_CHAR_LIMIT = 8_000;
+export const LONG_USER_MESSAGE_LINE_LIMIT = 120;
+
+export interface LongUserMessageStats {
+  characters: number;
+  lines: number;
+  compact: boolean;
+}
+
+/** 只遍历一次正文，避免为统计行数创建完整字符串数组。 */
+export function getLongUserMessageStats(content: string): LongUserMessageStats {
+  let lines = 1;
+  for (let index = 0; index < content.length; index++) {
+    if (content.charCodeAt(index) === 10) lines++;
+  }
+  return {
+    characters: content.length,
+    lines,
+    compact: content.length > LONG_USER_MESSAGE_CHAR_LIMIT || lines > LONG_USER_MESSAGE_LINE_LIMIT,
+  };
+}
diff --git a/lib/multi-skill-command.test.mjs b/lib/multi-skill-command.test.mjs
new file mode 100644
index 00000000..6fc82136
--- /dev/null
+++ b/lib/multi-skill-command.test.mjs
@@ -0,0 +1,29 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+import { mkdtempSync, writeFileSync } from "node:fs";
+import { join } from "node:path";
+import { tmpdir } from "node:os";
+import { createJiti } from "jiti";
+
+const jiti = createJiti(import.meta.url);
+const { expandMultiSkillCommand } = await jiti.import("./multi-skill-command.ts");
+
+test("展开多个 skill 并保留共享用户输入", () => {
+  const dir = mkdtempSync(join(tmpdir(), "pi-web-skills-"));
+  const sshPath = join(dir, "ssh.md");
+  const databasePath = join(dir, "database.md");
+  writeFileSync(sshPath, "---\nname: ssh\n---\nSSH 说明\n");
+  writeFileSync(databasePath, "数据库说明\n");
+
+  const result = expandMultiSkillCommand(
+    "/skill:ssh /skill:database 测试连接",
+    [
+      { name: "ssh", filePath: sshPath, baseDir: dir },
+      { name: "database", filePath: databasePath, baseDir: dir },
+    ],
+  );
+
+  assert.equal(result.expanded, true);
+  assert.match(result.text, /<skill name="ssh"[\s\S]*SSH 说明[\s\S]*<skill name="database"/);
+  assert.ok(result.text.endsWith("\n\n测试连接"));
+});
diff --git a/lib/multi-skill-command.ts b/lib/multi-skill-command.ts
new file mode 100644
index 00000000..d223ccfb
--- /dev/null
+++ b/lib/multi-skill-command.ts
@@ -0,0 +1,37 @@
+import { readFileSync } from "fs";
+
+interface LoadedSkill {
+  name: string;
+  filePath: string;
+  baseDir: string;
+}
+
+export interface ExpandedMultiSkillCommand {
+  text: string;
+  expanded: boolean;
+}
+
+function stripFrontmatter(content: string): string {
+  return content.replace(/^---\r?\n[\s\S]*?\r?\n---\r?\n/, "").trim();
+}
+
+/** 展开 Pi 原生只处理第一个的多 skill 命令；单 skill 仍交给 Pi 自己处理。 */
+export function expandMultiSkillCommand(text: string, loadedSkills: LoadedSkill[]): ExpandedMultiSkillCommand {
+  const match = text.match(/^((?:\/skill:[^\s]+\s+){2,})([\s\S]*)$/);
+  if (!match) return { text, expanded: false };
+
+  const names = [...match[1].matchAll(/\/skill:([^\s]+)/g)].map((item) => item[1]);
+  const skills = names.map((name) => loadedSkills.find((skill) => skill.name === name));
+  if (skills.some((skill) => !skill)) return { text, expanded: false };
+
+  const blocks = skills.map((skill) => {
+    const resolved = skill!;
+    const body = stripFrontmatter(readFileSync(resolved.filePath, "utf-8"));
+    return `<skill name="${resolved.name}" location="${resolved.filePath}">\nReferences are relative to ${resolved.baseDir}.\n\n${body}\n</skill>`;
+  });
+  const userMessage = match[2].trim();
+  return {
+    text: `${blocks.join("\n\n")}${userMessage ? `\n\n${userMessage}` : ""}`,
+    expanded: true,
+  };
+}
diff --git a/lib/pi-types.ts b/lib/pi-types.ts
index c2b68e21..af7dbf6c 100644
--- a/lib/pi-types.ts
+++ b/lib/pi-types.ts
@@ -57,6 +57,8 @@ interface PromptTemplateLike {
 interface SkillLike {
   name: string;
   description?: string;
+  filePath: string;
+  baseDir: string;
   sourceInfo: SlashCommandInfo["sourceInfo"];
 }
 
@@ -136,6 +138,7 @@ export interface AgentSessionLike {
   reload(options?: { beforeSessionStart?: () => void | Promise<void> }): Promise<void>;
   subscribe(listener: (event: AgentSessionEvent) => void): () => void;
   prompt(text: string, options?: {
+    expandPromptTemplates?: boolean;
     images?: Array<{ type: "image"; data: string; mimeType: string }>;
     streamingBehavior?: "steer" | "followUp";
     source?: "interactive" | "rpc";
diff --git a/lib/project-directories.test.mjs b/lib/project-directories.test.mjs
new file mode 100644
index 00000000..aa8dc1b6
--- /dev/null
+++ b/lib/project-directories.test.mjs
@@ -0,0 +1,45 @@
+import assert from "node:assert/strict";
+import fs from "node:fs";
+import os from "node:os";
+import path from "node:path";
+import test from "node:test";
+import { pathToFileURL } from "node:url";
+import ts from "typescript";
+
+const sourcePath = path.join(import.meta.dirname, "project-directories.ts");
+const atomicFileUrl = pathToFileURL(path.join(import.meta.dirname, "atomic-file.ts")).href;
+const codingAgentUrl = import.meta.resolve("@earendil-works/pi-coding-agent");
+const source = fs.readFileSync(sourcePath, "utf8")
+  .replace('"./atomic-file"', JSON.stringify(atomicFileUrl))
+  .replace('"@earendil-works/pi-coding-agent"', JSON.stringify(codingAgentUrl));
+const transpiled = ts.transpileModule(source, {
+  compilerOptions: { module: ts.ModuleKind.ESNext, target: ts.ScriptTarget.ES2022 },
+}).outputText;
+const {
+  addProjectDirectory,
+  readProjectDirectories,
+  removeProjectDirectory,
+} = await import(`data:text/javascript;base64,${Buffer.from(transpiled).toString("base64")}`);
+
+test("跨请求持久化、去重并移除项目目录", (t) => {
+  const root = fs.mkdtempSync(path.join(os.tmpdir(), "pi-web-projects-"));
+  const file = path.join(root, "pi-web-projects.json");
+  t.after(() => fs.rmSync(root, { recursive: true, force: true }));
+
+  addProjectDirectory("/workspace/b", file);
+  addProjectDirectory("/workspace/a", file);
+  addProjectDirectory("/workspace/b", file);
+  assert.deepEqual(readProjectDirectories(file), ["/workspace/b", "/workspace/a"]);
+
+  removeProjectDirectory("/workspace/b", file);
+  assert.deepEqual(readProjectDirectories(file), ["/workspace/a"]);
+  if (process.platform !== "win32") assert.equal(fs.statSync(file).mode & 0o777, 0o600);
+});
+
+test("配置文件损坏时返回空目录列表", (t) => {
+  const root = fs.mkdtempSync(path.join(os.tmpdir(), "pi-web-projects-invalid-"));
+  const file = path.join(root, "pi-web-projects.json");
+  t.after(() => fs.rmSync(root, { recursive: true, force: true }));
+  fs.writeFileSync(file, "not json");
+  assert.deepEqual(readProjectDirectories(file), []);
+});
diff --git a/lib/project-directories.ts b/lib/project-directories.ts
new file mode 100644
index 00000000..6a4ece82
--- /dev/null
+++ b/lib/project-directories.ts
@@ -0,0 +1,49 @@
+import { existsSync, mkdirSync, readFileSync, statSync } from "fs";
+import { dirname, resolve } from "path";
+import { getAgentDir } from "@earendil-works/pi-coding-agent";
+import { writePrivateFileAtomicSync } from "./atomic-file";
+
+interface ProjectDirectoriesFile {
+  projects: string[];
+}
+
+export function getProjectDirectoriesPath(): string {
+  return resolve(getAgentDir(), "pi-web-projects.json");
+}
+
+export function readProjectDirectories(path = getProjectDirectoriesPath()): string[] {
+  if (!existsSync(path)) return [];
+  try {
+    const data = JSON.parse(readFileSync(path, "utf8")) as Partial<ProjectDirectoriesFile>;
+    if (!Array.isArray(data.projects)) return [];
+    return [...new Set(data.projects.filter((project): project is string => typeof project === "string" && project.length > 0))];
+  } catch (error) {
+    console.error("读取 Pi Web 项目目录配置失败", error);
+    return [];
+  }
+}
+
+export function normalizeProjectDirectory(value: unknown): string {
+  if (typeof value !== "string" || !value.trim()) throw new Error("cwd required");
+  const cwd = resolve(value.trim());
+  if (!statSync(cwd).isDirectory()) throw new Error("cwd must be a directory");
+  return cwd;
+}
+
+function writeProjectDirectories(projects: string[], path = getProjectDirectoriesPath()): void {
+  mkdirSync(dirname(path), { recursive: true });
+  writePrivateFileAtomicSync(path, `${JSON.stringify({ projects }, null, 2)}\n`);
+}
+
+export function addProjectDirectory(cwd: string, path = getProjectDirectoriesPath()): string[] {
+  const projects = readProjectDirectories(path);
+  const next = [cwd, ...projects.filter((project) => project !== cwd)];
+  writeProjectDirectories(next, path);
+  return next;
+}
+
+export function removeProjectDirectory(cwd: string, path = getProjectDirectoriesPath()): string[] {
+  const next = readProjectDirectories(path).filter((project) => project !== cwd);
+  writeProjectDirectories(next, path);
+  return next;
+}
diff --git a/lib/rpc-manager.ts b/lib/rpc-manager.ts
index d9adaf9c..eb7aba31 100644
--- a/lib/rpc-manager.ts
+++ b/lib/rpc-manager.ts
@@ -5,6 +5,7 @@ import { randomUUID } from "crypto";
 import { existsSync, realpathSync, writeFileSync } from "fs";
 import { resolve } from "path";
 import { validateAgentImages } from "./image-attachments";
+import { expandMultiSkillCommand } from "./multi-skill-command";
 import { invalidateModelsCache } from "./models-cache";
 import { resolveVisibleModels, selectInitialModelScope } from "./model-scope";
 import { cacheSessionPath, invalidateSessionListCache } from "./session-reader";
@@ -336,7 +337,12 @@ export class AgentSessionWrapper {
         const streamingBehavior = command.streamingBehavior as "steer" | "followUp" | undefined;
         this.promptRunning = true;
         notifyRunningChange();
-        this.inner.prompt(command.message as string, {
+        const multiSkill = expandMultiSkillCommand(
+          command.message as string,
+          this.inner.resourceLoader.getSkills().skills,
+        );
+        this.inner.prompt(multiSkill.text, {
+          ...(multiSkill.expanded ? { expandPromptTemplates: false } : {}),
           ...(promptImages?.length ? { images: promptImages } : {}),
           ...(streamingBehavior ? { streamingBehavior } : {}),
           source: "rpc",
diff --git a/lib/session-reader.ts b/lib/session-reader.ts
index 6c0da255..f0e0569e 100644
--- a/lib/session-reader.ts
+++ b/lib/session-reader.ts
@@ -41,7 +41,9 @@ async function loadAllSessions(): Promise<SessionInfo[]> {
       firstMessage: s.firstMessage || "(no messages)",
       parentSessionId: s.parentSessionPath ? pathToId.get(sessionPathKey(s.parentSessionPath)) : undefined,
       projectRoot: project?.projectRoot ?? s.cwd,
-      ...(project?.isWorktree && project.branch ? { worktreeBranch: project.branch } : {}),
+      // 主 checkout 也是一个 worktree；统一把所有顶层 checkout 的分支
+      // 传给侧边栏，避免 main 会话缺少 worktree 标识。
+      ...(project?.isTopLevel && project.branch ? { worktreeBranch: project.branch } : {}),
     };
   });
 }
diff --git a/lib/skill-block.test.mjs b/lib/skill-block.test.mjs
new file mode 100644
index 00000000..f1f3c339
--- /dev/null
+++ b/lib/skill-block.test.mjs
@@ -0,0 +1,35 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+import { createJiti } from "jiti";
+
+const jiti = createJiti(import.meta.url);
+const { parseSkillBlock, parseSkillMessage } = await jiti.import("./skill-block.ts");
+
+test("解析 skill 正文和附加用户输入", () => {
+  assert.deepEqual(
+    parseSkillBlock('<skill name="pdf" location="/skills/pdf/SKILL.md">\n完整说明\n</skill>\n\n检查 report.pdf'),
+    {
+      name: "pdf",
+      location: "/skills/pdf/SKILL.md",
+      content: "完整说明",
+      userMessage: "检查 report.pdf",
+    },
+  );
+});
+
+test("普通用户消息不按 skill 处理", () => {
+  assert.equal(parseSkillBlock("普通消息"), null);
+});
+
+test("解析多个 skill 和共享的附加输入", () => {
+  assert.deepEqual(
+    parseSkillMessage('<skill name="ssh" location="/ssh/SKILL.md">\nSSH 说明\n</skill>\n\n<skill name="database" location="/database/SKILL.md">\n数据库说明\n</skill>\n\n测试连接'),
+    {
+      skills: [
+        { name: "ssh", location: "/ssh/SKILL.md", content: "SSH 说明" },
+        { name: "database", location: "/database/SKILL.md", content: "数据库说明" },
+      ],
+      userMessage: "测试连接",
+    },
+  );
+});
diff --git a/lib/skill-block.ts b/lib/skill-block.ts
new file mode 100644
index 00000000..8ecfb79b
--- /dev/null
+++ b/lib/skill-block.ts
@@ -0,0 +1,39 @@
+export interface ParsedSkillBlock {
+  name: string;
+  location: string;
+  content: string;
+  userMessage?: string;
+}
+
+export interface ParsedSkillMessage {
+  skills: ParsedSkillBlock[];
+  userMessage?: string;
+}
+
+/** 解析一个或多个连续展开的 skill，以及它们共享的附加用户输入。 */
+export function parseSkillMessage(text: string): ParsedSkillMessage | null {
+  const skills: ParsedSkillBlock[] = [];
+  let remaining = text;
+  const blockPattern = /^<skill name="([^"]+)" location="([^"]+)">\r?\n([\s\S]*?)\r?\n<\/skill>(?:\r?\n\r?\n|$)/;
+
+  while (remaining.startsWith("<skill ")) {
+    const match = remaining.match(blockPattern);
+    if (!match) return null;
+    skills.push({ name: match[1], location: match[2], content: match[3] });
+    remaining = remaining.slice(match[0].length);
+  }
+
+  if (skills.length === 0) return null;
+  const userMessage = remaining.trim() || undefined;
+  return { skills, userMessage };
+}
+
+/** 解析 pi 展开 /skill:name 后写入会话的用户消息。 */
+export function parseSkillBlock(text: string): ParsedSkillBlock | null {
+  const message = parseSkillMessage(text);
+  if (!message || message.skills.length !== 1) return null;
+  return {
+    ...message.skills[0],
+    userMessage: message.userMessage,
+  };
+}
diff --git a/lib/slash-command.test.mjs b/lib/slash-command.test.mjs
new file mode 100644
index 00000000..8ad4da10
--- /dev/null
+++ b/lib/slash-command.test.mjs
@@ -0,0 +1,55 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+import { createJiti } from "jiti";
+
+const jiti = createJiti(import.meta.url);
+const { applySlashSelection, findSlashQuery } = await jiti.import("./slash-command.ts");
+
+test("识别输入开头的斜杠查询", () => {
+  assert.deepEqual(findSlashQuery("/skill:pdf"), {
+    query: "skill:pdf",
+    start: 0,
+    inline: false,
+  });
+});
+
+test("识别已有正文后的斜杠查询", () => {
+  const slash = findSlashQuery("分析这个文件 /pdf");
+  assert.deepEqual(slash, { query: "pdf", start: 7, inline: true });
+  assert.equal(
+    applySlashSelection("分析这个文件 /pdf", slash, "skill:pdf"),
+    "/skill:pdf 分析这个文件 ",
+  );
+});
+
+test("识别紧跟在已有正文后的斜杠查询", () => {
+  const slash = findSlashQuery("分析这个文件/pdf");
+  assert.deepEqual(slash, { query: "pdf", start: 6, inline: true });
+  assert.equal(
+    applySlashSelection("分析这个文件/pdf", slash, "skill:pdf"),
+    "/skill:pdf 分析这个文件 ",
+  );
+});
+
+test("忽略已带参数或不完整的斜杠片段", () => {
+  assert.equal(findSlashQuery("/skill:pdf 分析"), null);
+  assert.equal(findSlashQuery("路径/foo/bar"), null);
+});
+
+test("连续输入斜杠仍打开同一个查询", () => {
+  assert.deepEqual(findSlashQuery("你还 ////"), {
+    query: "",
+    start: 3,
+    inline: true,
+  });
+});
+
+test("连续选择多个 skill 时保留全部 skill，并把用户输入放在最后", () => {
+  const value = "/skill:agent-ssh-cli 测试连接 /data";
+  const slash = findSlashQuery(value);
+  assert.deepEqual(slash, { query: "data", start: 26, inline: true });
+  assert.equal(
+    applySlashSelection(value, slash, "skill:agent-database-cli"),
+    "/skill:agent-ssh-cli /skill:agent-database-cli 测试连接 ",
+  );
+});
diff --git a/lib/slash-command.ts b/lib/slash-command.ts
new file mode 100644
index 00000000..b416b39f
--- /dev/null
+++ b/lib/slash-command.ts
@@ -0,0 +1,44 @@
+export interface SlashQuery {
+  query: string;
+  start: number;
+  inline: boolean;
+}
+
+/** 识别输入末尾的斜杠命令；已有正文时仅用于选择 skill。 */
+export function findSlashQuery(value: string): SlashQuery | null {
+  let queryStart = value.length;
+  while (queryStart > 0 && !/[/\s]/.test(value[queryStart - 1])) queryStart--;
+  if (queryStart === 0 || value[queryStart - 1] !== "/") return null;
+
+  let start = queryStart - 1;
+  while (start > 0 && value[start - 1] === "/") start--;
+
+  let tokenStart = start;
+  while (tokenStart > 0 && !/\s/.test(value[tokenStart - 1])) tokenStart--;
+  if (value.slice(tokenStart, start).includes("/")) return null;
+
+  let inline = start > 0;
+  if (inline) {
+    let previous = start - 1;
+    while (previous >= 0 && /\s/.test(value[previous])) previous--;
+    inline = previous >= 0;
+  }
+  return {
+    query: value.slice(queryStart).toLowerCase(),
+    start,
+    inline,
+  };
+}
+
+/** 把行尾选择的 skill 调整到开头，保持 pi 的 /skill:name 参数语义。 */
+export function applySlashSelection(value: string, slash: SlashQuery, commandName: string): string {
+  if (!slash.inline) return `/${commandName} `;
+  const beforeSelection = value.slice(0, slash.start);
+  const existingSkills = [...beforeSelection.matchAll(/(?:^|\s)(\/skill:[^\s]+)/g)].map((match) => match[1]);
+  const selectedSkill = `/${commandName}`;
+  const skills = existingSkills.includes(selectedSkill)
+    ? existingSkills
+    : [...existingSkills, selectedSkill];
+  const existingText = beforeSelection.replace(/(?:^|\s)\/skill:[^\s]+/g, " ").trim();
+  return `${skills.join(" ")}${existingText ? ` ${existingText}` : ""} `;
+}
diff --git a/next.config.ts b/next.config.ts
index fb7c5cf0..7602cde1 100644
--- a/next.config.ts
+++ b/next.config.ts
@@ -10,6 +10,7 @@ try {
 } catch { /* package not found, use default */ }
 
 const nextConfig: NextConfig = {
+  devIndicators: false,
   serverExternalPackages: [
     "undici",
     "@earendil-works/pi-coding-agent",
@@ -17,7 +18,7 @@ const nextConfig: NextConfig = {
     "@earendil-works/pi-ai",
     "@earendil-works/pi-tui",
   ],
-  allowedDevOrigins: ['192.168.*.*'],
+  allowedDevOrigins: ["192.168.*.*", "10.0.0.*", "pi.znzme.com"],
   async headers() {
     return [
       {
diff --git a/public/sw.js b/public/sw.js
index 89ff2423..937e7550 100644
--- a/public/sw.js
+++ b/public/sw.js
@@ -14,11 +14,16 @@ self.addEventListener("install", (event) => {
   event.waitUntil(
     caches
       .open(STATIC_CACHE)
-      .then((cache) => cache.addAll(PRECACHE_URLS))
-      .then(() => self.skipWaiting()),
+      .then((cache) => cache.addAll(PRECACHE_URLS)),
   );
 });
 
+self.addEventListener("message", (event) => {
+  if (event.data?.type === "SKIP_WAITING") {
+    void self.skipWaiting();
+  }
+});
+
 self.addEventListener("activate", (event) => {
   event.waitUntil(
     caches
@@ -34,6 +39,21 @@ self.addEventListener("activate", (event) => {
   );
 });
 
+self.addEventListener("notificationclick", (event) => {
+  event.notification.close();
+  const targetUrl = new URL(event.notification.data?.url || "/", self.location.origin).href;
+  event.waitUntil(
+    self.clients.matchAll({ type: "window", includeUncontrolled: true }).then(async (clients) => {
+      const client = clients.find((candidate) => candidate.url.startsWith(self.location.origin));
+      if (client) {
+        await client.navigate(targetUrl);
+        return client.focus();
+      }
+      return self.clients.openWindow(targetUrl);
+    }),
+  );
+});
+
 self.addEventListener("fetch", (event) => {
   const { request } = event;
   if (request.method !== "GET") return;