diff --git a/package-lock.json b/package-lock.json
index 66b8e03..ce6292b 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "goodbuddy",
-  "version": "0.8.6",
+  "version": "0.8.8",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "goodbuddy",
-      "version": "0.8.6",
+      "version": "0.8.8",
       "license": "UNLICENSED",
       "dependencies": {
         "@modelcontextprotocol/sdk": "^1.30.0",
diff --git a/package.json b/package.json
index 2daacc3..c41f33e 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "goodbuddy",
-  "version": "0.8.6",
+  "version": "0.8.8",
   "private": true,
   "description": "Secure desktop AI workspace with controlled Agent Runtimes",
   "desktopName": "GoodBuddy",
diff --git a/src/main/application-settings-store.test.ts b/src/main/application-settings-store.test.ts
index 08b4b1a..6746919 100644
--- a/src/main/application-settings-store.test.ts
+++ b/src/main/application-settings-store.test.ts
@@ -11,6 +11,7 @@ import { afterEach, describe, expect, it } from 'vitest'
 import {
   ApplicationSettingsStore,
   applicationSettingsSchema,
+  applicationSettingsUpdateSchema,
   defaultApplicationSettings
 } from './application-settings-store'
 
@@ -51,18 +52,26 @@ describe('ApplicationSettingsStore', () => {
     await expect(readdir(directory)).resolves.toEqual([])
   })
 
-  it('persists only the versioned startup update preference', async () => {
+  it('persists versioned application preferences', async () => {
     const { directory, filePath, store } = await createStore()
 
     await expect(
-      store.update({ checkUpdatesOnStartup: false })
-    ).resolves.toEqual({ checkUpdatesOnStartup: false })
+      store.update({
+        checkUpdatesOnStartup: false,
+        magicNotesEnabled: false
+      })
+    ).resolves.toEqual({
+      checkUpdatesOnStartup: false,
+      magicNotesEnabled: false
+    })
     await expect(store.get()).resolves.toEqual({
-      checkUpdatesOnStartup: false
+      checkUpdatesOnStartup: false,
+      magicNotesEnabled: false
     })
     expect(JSON.parse(await readFile(filePath, 'utf8'))).toEqual({
-      version: 1,
-      checkUpdatesOnStartup: false
+      version: 2,
+      checkUpdatesOnStartup: false,
+      magicNotesEnabled: false
     })
     expect(
       (await readdir(directory)).filter((name) => name.endsWith('.tmp'))
@@ -73,38 +82,103 @@ describe('ApplicationSettingsStore', () => {
     const { directory } = await createStore()
     const filePath = join(directory, 'nested', 'application-settings.json')
     const store = new ApplicationSettingsStore(filePath)
-    await store.update({ checkUpdatesOnStartup: false })
+    await store.update({
+      checkUpdatesOnStartup: false,
+      magicNotesEnabled: false
+    })
 
     await expect(
       new ApplicationSettingsStore(filePath).get()
-    ).resolves.toEqual({ checkUpdatesOnStartup: false })
+    ).resolves.toEqual({
+      checkUpdatesOnStartup: false,
+      magicNotesEnabled: false
+    })
   })
 
-  it('strictly rejects unknown, missing, and mistyped input', async () => {
-    const { directory, store } = await createStore()
+  it.each([1, 2])(
+    'loads version %s settings missing the field with Magic Notes disabled',
+    async (version) => {
+      const { filePath, store } = await createStore()
+      await writeFile(
+        filePath,
+        JSON.stringify({
+          version,
+          checkUpdatesOnStartup: false
+        }),
+        'utf8'
+      )
+
+      await expect(store.get()).resolves.toEqual({
+        checkUpdatesOnStartup: false,
+        magicNotesEnabled: false
+      })
+    }
+  )
+
+  it('strictly rejects incomplete full settings', () => {
     for (const input of [
       {},
       { checkUpdatesOnStartup: 'true' },
-      { checkUpdatesOnStartup: true, anotherSetting: true },
+      {
+        checkUpdatesOnStartup: true,
+        magicNotesEnabled: true,
+        anotherSetting: true
+      },
+      { checkUpdatesOnStartup: true },
       null
     ]) {
       expect(applicationSettingsSchema.safeParse(input).success).toBe(
         false
       )
+    }
+  })
+
+  it('strictly rejects empty, unknown, and mistyped updates', async () => {
+    const { directory, store } = await createStore()
+    for (const input of [
+      {},
+      { checkUpdatesOnStartup: 'true' },
+      { anotherSetting: true },
+      null
+    ]) {
+      expect(
+        applicationSettingsUpdateSchema.safeParse(input).success
+      ).toBe(false)
       await expect(store.update(input)).rejects.toThrow()
     }
     await expect(readdir(directory)).resolves.toEqual([])
   })
 
+  it('merges partial updates without overwriting other settings', async () => {
+    const { store } = await createStore()
+
+    await store.update({ magicNotesEnabled: true })
+    await expect(
+      store.update({ checkUpdatesOnStartup: false })
+    ).resolves.toEqual({
+      checkUpdatesOnStartup: false,
+      magicNotesEnabled: true
+    })
+  })
+
   it.each([
     '{not-json',
-    JSON.stringify({ version: 2, checkUpdatesOnStartup: false }),
     JSON.stringify({
-      version: 1,
+      version: 3,
       checkUpdatesOnStartup: false,
+      magicNotesEnabled: false
+    }),
+    JSON.stringify({
+      version: 2,
+      checkUpdatesOnStartup: false,
+      magicNotesEnabled: true,
       injected: true
     }),
-    JSON.stringify({ version: 1, checkUpdatesOnStartup: 'false' })
+    JSON.stringify({
+      version: 2,
+      checkUpdatesOnStartup: 'false',
+      magicNotesEnabled: true
+    })
   ])('isolates corrupt persisted data and restores defaults', async (data) => {
     const { directory, filePath, store } = await createStore()
     await writeFile(filePath, data, 'utf8')
@@ -142,28 +216,48 @@ describe('ApplicationSettingsStore', () => {
     const { filePath, store } = await createStore()
 
     await Promise.all([
-      store.update({ checkUpdatesOnStartup: false }),
-      store.update({ checkUpdatesOnStartup: true }),
-      store.update({ checkUpdatesOnStartup: false })
+      store.update({
+        checkUpdatesOnStartup: false,
+        magicNotesEnabled: true
+      }),
+      store.update({
+        checkUpdatesOnStartup: true,
+        magicNotesEnabled: false
+      }),
+      store.update({
+        checkUpdatesOnStartup: false,
+        magicNotesEnabled: false
+      })
     ])
 
     await expect(store.get()).resolves.toEqual({
-      checkUpdatesOnStartup: false
+      checkUpdatesOnStartup: false,
+      magicNotesEnabled: false
     })
     expect(JSON.parse(await readFile(filePath, 'utf8'))).toEqual({
-      version: 1,
-      checkUpdatesOnStartup: false
+      version: 2,
+      checkUpdatesOnStartup: false,
+      magicNotesEnabled: false
     })
   })
 
   it('continues accepting updates after a validation failure', async () => {
     const { store } = await createStore()
     await expect(
-      store.update({ checkUpdatesOnStartup: 'invalid' })
+      store.update({
+        checkUpdatesOnStartup: 'invalid',
+        magicNotesEnabled: true
+      })
     ).rejects.toThrow()
 
     await expect(
-      store.update({ checkUpdatesOnStartup: false })
-    ).resolves.toEqual({ checkUpdatesOnStartup: false })
+      store.update({
+        checkUpdatesOnStartup: false,
+        magicNotesEnabled: true
+      })
+    ).resolves.toEqual({
+      checkUpdatesOnStartup: false,
+      magicNotesEnabled: true
+    })
   })
 })
diff --git a/src/main/application-settings-store.ts b/src/main/application-settings-store.ts
index 1f97c30..928079c 100644
--- a/src/main/application-settings-store.ts
+++ b/src/main/application-settings-store.ts
@@ -10,12 +10,23 @@ import { dirname } from 'node:path'
 import { z } from 'zod'
 import {
   applicationSettingsSchema,
+  applicationSettingsUpdateSchema,
   type ApplicationSettings
 } from '../shared/application-settings-contracts'
-export { applicationSettingsSchema } from '../shared/application-settings-contracts'
+export {
+  applicationSettingsSchema,
+  applicationSettingsUpdateSchema
+} from '../shared/application-settings-contracts'
 export type { ApplicationSettings } from '../shared/application-settings-contracts'
 
-const CURRENT_SETTINGS_VERSION = 1
+const CURRENT_SETTINGS_VERSION = 2
+
+const legacyStoredApplicationSettingsSchema = z
+  .object({
+    version: z.union([z.literal(1), z.literal(2)]),
+    checkUpdatesOnStartup: z.boolean()
+  })
+  .strict()
 
 const storedApplicationSettingsSchema = applicationSettingsSchema
   .extend({
@@ -28,7 +39,8 @@ type StoredApplicationSettings = z.infer<
 >
 
 export const defaultApplicationSettings: ApplicationSettings = {
-  checkUpdatesOnStartup: true
+  checkUpdatesOnStartup: true,
+  magicNotesEnabled: false
 }
 
 function isMissingFile(error: unknown): boolean {
@@ -81,6 +93,17 @@ export class ApplicationSettingsStore {
       }
       const result = storedApplicationSettingsSchema.safeParse(parsed)
       if (!result.success) {
+        const legacyResult =
+          legacyStoredApplicationSettingsSchema.safeParse(parsed)
+        if (legacyResult.success) {
+          this.settings = {
+            version: CURRENT_SETTINGS_VERSION,
+            checkUpdatesOnStartup:
+              legacyResult.data.checkUpdatesOnStartup,
+            magicNotesEnabled: false
+          }
+          return this.settings
+        }
         await this.isolateCorruptFile()
         this.settings = {
           version: CURRENT_SETTINGS_VERSION,
@@ -106,16 +129,19 @@ export class ApplicationSettingsStore {
   async get(): Promise<ApplicationSettings> {
     const stored = await this.loadStored()
     return {
-      checkUpdatesOnStartup: stored.checkUpdatesOnStartup
+      checkUpdatesOnStartup: stored.checkUpdatesOnStartup,
+      magicNotesEnabled: stored.magicNotesEnabled
     }
   }
 
   update(input: unknown): Promise<ApplicationSettings> {
     const operation = this.updateQueue.then(async () => {
-      const settings = applicationSettingsSchema.parse(input)
+      const updates = applicationSettingsUpdateSchema.parse(input)
+      const current = await this.loadStored()
       const next: StoredApplicationSettings = {
-        version: CURRENT_SETTINGS_VERSION,
-        ...settings
+        ...current,
+        ...updates,
+        version: CURRENT_SETTINGS_VERSION
       }
       await mkdir(dirname(this.filePath), { recursive: true })
       const temporaryPath =
@@ -137,7 +163,8 @@ export class ApplicationSettingsStore {
       }
       this.settings = next
       return {
-        checkUpdatesOnStartup: next.checkUpdatesOnStartup
+        checkUpdatesOnStartup: next.checkUpdatesOnStartup,
+        magicNotesEnabled: next.magicNotesEnabled
       }
     })
     this.updateQueue = operation.then(
diff --git a/src/main/ipc.ts b/src/main/ipc.ts
index 5244579..c907f95 100644
--- a/src/main/ipc.ts
+++ b/src/main/ipc.ts
@@ -63,7 +63,7 @@ import {
   dingTalkChannelSettingsInputSchema,
   weComChannelSettingsInputSchema
 } from '../shared/channel-settings-contracts'
-import { applicationSettingsSchema } from '../shared/application-settings-contracts'
+import { applicationSettingsUpdateSchema } from '../shared/application-settings-contracts'
 import {
   speechModelActionInputSchema,
   speechModelSelectionInputSchema
@@ -834,6 +834,7 @@ export function registerIpcHandlers(
       channel: keyof typeof projectChannelLabels
       channelLabel: string
       senderDisplay: string
+      projectId: string
       projectName: string
       rootPath: string
       conversationId: string
@@ -1027,6 +1028,8 @@ export function registerIpcHandlers(
           publishRemoteActivity({
             requestId,
             conversationId: remoteContext.conversationId,
+            projectId: remoteContext.projectId,
+            projectName: remoteContext.projectName,
             channel: remoteContext.channel,
             kind: 'tool',
             callId: taskEvent.callId,
@@ -1450,6 +1453,8 @@ export function registerIpcHandlers(
     publishRemoteActivity({
       requestId: remoteTaskId,
       conversationId: remoteConversation.id,
+      projectId: project.id,
+      projectName: project.name,
       channel,
       kind: 'request',
       title: `${channelLabel} · ${senderDisplay}`,
@@ -1490,6 +1495,8 @@ export function registerIpcHandlers(
         publishRemoteActivity({
           requestId: remoteTaskId,
           conversationId: remoteConversation.id,
+          projectId: project.id,
+          projectName: project.name,
           channel,
           kind: 'result',
           title: `${channelLabel}远程执行不可用`,
@@ -1522,6 +1529,8 @@ export function registerIpcHandlers(
         publishRemoteActivity({
           requestId: remoteTaskId,
           conversationId: remoteConversation.id,
+          projectId: project.id,
+          projectName: project.name,
           channel,
           kind: 'result',
           title: `${channelLabel}远程执行不可用`,
@@ -1554,6 +1563,7 @@ export function registerIpcHandlers(
           channel,
           channelLabel,
           senderDisplay,
+          projectId: project.id,
           projectName: project.name,
           rootPath: project.rootPath,
           conversationId: remoteConversation.id,
@@ -1604,6 +1614,8 @@ export function registerIpcHandlers(
     publishRemoteActivity({
       requestId: remoteTaskId,
       conversationId: remoteConversation.id,
+      projectId: project.id,
+      projectName: project.name,
       channel,
       kind: 'result',
       title:
@@ -2409,7 +2421,7 @@ export function registerIpcHandlers(
         throw new Error('应用设置服务不可用')
       }
       return applicationSettingsStore.update(
-        applicationSettingsSchema.parse(input)
+        applicationSettingsUpdateSchema.parse(input)
       )
     }
   )
diff --git a/src/main/window.ts b/src/main/window.ts
index 58058b2..6a77485 100644
--- a/src/main/window.ts
+++ b/src/main/window.ts
@@ -60,8 +60,8 @@ export function createMainWindow(shouldQuit: () => boolean): BrowserWindow {
   const window = new BrowserWindow({
     width: 1180,
     height: 760,
-    minWidth: 920,
-    minHeight: 620,
+    minWidth: 680,
+    minHeight: 560,
     show: false,
     frame: false,
     ...(usableIcon ? { icon: usableIcon } : {}),
diff --git a/src/preload/index.ts b/src/preload/index.ts
index eb936a2..8da1379 100644
--- a/src/preload/index.ts
+++ b/src/preload/index.ts
@@ -61,6 +61,7 @@ import type {
 } from '../shared/channel-settings-contracts'
 import type {
   ApplicationSettings,
+  ApplicationSettingsUpdate,
   VersionCheckResult
 } from '../shared/application-settings-contracts'
 import type {
@@ -294,7 +295,7 @@ const desktopApi: DesktopApi = {
       ipcRenderer.invoke(
         ipcChannels.applicationSettingsGet
       ) as Promise<ApplicationSettings>,
-    updateSettings: (input: ApplicationSettings) =>
+    updateSettings: (input: ApplicationSettingsUpdate) =>
       ipcRenderer.invoke(
         ipcChannels.applicationSettingsUpdate,
         input
diff --git a/src/renderer/src/ActivityPanel.test.tsx b/src/renderer/src/ActivityPanel.test.tsx
index 624e9c7..14fd9b8 100644
--- a/src/renderer/src/ActivityPanel.test.tsx
+++ b/src/renderer/src/ActivityPanel.test.tsx
@@ -21,6 +21,7 @@ function makeRecord(
     id: `activity-${index}`,
     conversationId: `conversation-${index}`,
     requestId: `request-${index}`,
+    scope: { kind: 'global' },
     kind: 'tool',
     title: `活动 ${index}`,
     detail: `详情 ${index}`,
@@ -150,6 +151,26 @@ describe('ActivityPanel', () => {
     ).toBeDisabled()
   })
 
+  it('clears a filter that has no matching activity', () => {
+    render(
+      <ActivityPanel
+        onClear={vi.fn()}
+        onOpenConversation={vi.fn()}
+        records={[makeRecord(1)]}
+        tokenUsage={makeTokenUsage()}
+      />
+    )
+
+    fireEvent.click(screen.getByRole('button', { name: '进行中' }))
+    expect(screen.getByText('没有匹配的活动')).toBeInTheDocument()
+    fireEvent.click(screen.getByRole('button', { name: '清除筛选' }))
+
+    expect(
+      screen.getByRole('button', { name: '全部' })
+    ).toHaveAttribute('aria-pressed', 'true')
+    expect(screen.getByText('对话：活动 1')).toBeInTheDocument()
+  })
+
   it('labels Subagent activity as child expert work', () => {
     render(
       <ActivityPanel
@@ -208,6 +229,32 @@ describe('ActivityPanel', () => {
     expect(groups[0]!.querySelectorAll('article')).toHaveLength(2)
   })
 
+  it('shows immutable scope snapshots on groups and records', () => {
+    const projectRecord: ActivityRecord = {
+      ...makeRecord(1),
+      scope: {
+        kind: 'project',
+        projectId: 'project-1',
+        projectName: '项目甲'
+      }
+    }
+    const unavailableRecord: ActivityRecord = {
+      ...makeRecord(2),
+      scope: { kind: 'unavailable' }
+    }
+    render(
+      <ActivityPanel
+        onClear={vi.fn()}
+        onOpenConversation={vi.fn()}
+        records={[projectRecord, unavailableRecord]}
+        tokenUsage={makeTokenUsage()}
+      />
+    )
+
+    expect(screen.getAllByText('项目：项目甲')).toHaveLength(2)
+    expect(screen.getAllByText('范围不可用')).toHaveLength(2)
+  })
+
   it('uses the shared page hierarchy and explicit global scope', () => {
     render(
       <ActivityPanel
diff --git a/src/renderer/src/ActivityPanel.tsx b/src/renderer/src/ActivityPanel.tsx
index 3e69cbd..29bd714 100644
--- a/src/renderer/src/ActivityPanel.tsx
+++ b/src/renderer/src/ActivityPanel.tsx
@@ -14,7 +14,9 @@ import {
   DestructiveConfirmActions,
   EmptyState,
   PageHeader,
-  SegmentedControl
+  ScopeBadge,
+  SegmentedControl,
+  type WorkspaceScope
 } from './WorkspacePrimitives'
 
 type ActivityFilter = 'all' | 'active' | 'failed'
@@ -136,10 +138,26 @@ type ActivityGroup = {
   conversationId: string
   title: string
   records: ActivityRecord[]
+  scope: ActivityRecord['scope']
   latestAt: number
   status: ActivityRecord['status']
 }
 
+function activityWorkspaceScope(
+  scope: ActivityRecord['scope']
+): WorkspaceScope {
+  if (scope.kind === 'project') {
+    return { kind: 'project', projectName: scope.projectName }
+  }
+  if (scope.kind === 'global') {
+    return { kind: 'global' }
+  }
+  return {
+    kind: 'unavailable',
+    explanation: '创建此活动记录时未能确定其归属范围。'
+  }
+}
+
 function groupActivityRecords(
   records: readonly ActivityRecord[],
   allRecords: readonly ActivityRecord[]
@@ -171,6 +189,7 @@ function groupActivityRecords(
         request?.title ??
         items[0]!.title,
       records: items,
+      scope: items[0]!.scope,
       latestAt: Math.max(...items.map((record) => record.createdAt)),
       status
     }
@@ -361,6 +380,17 @@ export function ActivityPanel({
 
       {filteredRecords.length === 0 ? (
         <EmptyState
+          action={
+            filter === 'all' ? undefined : (
+              <button
+                className="secondary-button"
+                onClick={() => setFilter('all')}
+                type="button"
+              >
+                清除筛选
+              </button>
+            )
+          }
           description={emptyMessage(filter)}
           icon={<Activity size={24} />}
           level="section"
@@ -379,6 +409,9 @@ export function ActivityPanel({
                   <span>
                     <strong>对话：{group.title}</strong>
                     <small>{group.records.length} 条活动</small>
+                    <ScopeBadge
+                      scope={activityWorkspaceScope(group.scope)}
+                    />
                   </span>
                   <span
                     className={`status-badge activity-item__status activity-item__status--${group.status}`}
@@ -413,6 +446,9 @@ export function ActivityPanel({
                               {time.display}
                             </time>
                           </header>
+                          <ScopeBadge
+                            scope={activityWorkspaceScope(record.scope)}
+                          />
                           <h3>{record.title}</h3>
                           {record.detail.length > 0 && <p>{record.detail}</p>}
                           <button
diff --git a/src/renderer/src/App.test.tsx b/src/renderer/src/App.test.tsx
index bb381ab..8d813df 100644
--- a/src/renderer/src/App.test.tsx
+++ b/src/renderer/src/App.test.tsx
@@ -26,6 +26,7 @@ vi.mock('./speech-recognition', async (importOriginal) => ({
 }))
 
 import App from './App'
+import { loadActivityRecords } from './activity-store'
 
 let agentListener: ((event: AgentEvent) => void) | undefined
 let browserListener: ((state: BrowserLiveState) => void) | undefined
@@ -610,9 +611,13 @@ describe('App', () => {
     }))
     api.updates = {
       getSettings: vi.fn(async () => ({
-        checkUpdatesOnStartup: true
+        checkUpdatesOnStartup: true,
+        magicNotesEnabled: true
+      })),
+      updateSettings: vi.fn(async () => ({
+        checkUpdatesOnStartup: true,
+        magicNotesEnabled: true
       })),
-      updateSettings: vi.fn(async (input) => input),
       check,
       openReleasePage: vi.fn(async () => {}),
       onResult: vi.fn(() => () => {})
@@ -651,9 +656,13 @@ describe('App', () => {
       .mockRejectedValueOnce(new Error('offline'))
     api.updates = {
       getSettings: vi.fn(async () => ({
-        checkUpdatesOnStartup: true
+        checkUpdatesOnStartup: true,
+        magicNotesEnabled: true
+      })),
+      updateSettings: vi.fn(async () => ({
+        checkUpdatesOnStartup: true,
+        magicNotesEnabled: true
       })),
-      updateSettings: vi.fn(async (input) => input),
       check,
       openReleasePage: vi.fn(async () => {}),
       onResult: vi.fn(() => () => {})
@@ -847,6 +856,114 @@ describe('App', () => {
     expect(await screen.findByRole('status')).toBeVisible()
   })
 
+  it('requires an accessible confirmation before permanently deleting a conversation', async () => {
+    render(<App />)
+    const menuTrigger = screen.getByLabelText(
+      '更多会话操作 新对话'
+    )
+    fireEvent.click(menuTrigger)
+    const deleteTrigger = screen.getByRole('button', {
+      name: '删除对话 新对话'
+    })
+    fireEvent.click(deleteTrigger)
+
+    const dialog = screen.getByRole('alertdialog', {
+      name: '确认永久删除对话 新对话'
+    })
+    expect(dialog).toHaveTextContent('将永久删除此会话的全部内容')
+    expect(dialog).toHaveTextContent(
+      '如果此会话有正在运行的任务，也会同时停止'
+    )
+    expect(dialog).toHaveTextContent('此操作不可恢复')
+    const cancel = screen.getByRole('button', {
+      name: '取消删除对话 新对话'
+    })
+    const confirm = screen.getByRole('button', {
+      name: '确认永久删除对话 新对话'
+    })
+    expect(cancel).toHaveFocus()
+
+    fireEvent.keyDown(dialog, { key: 'Tab' })
+    expect(confirm).toHaveFocus()
+    fireEvent.keyDown(dialog, { key: 'Tab', shiftKey: true })
+    expect(cancel).toHaveFocus()
+    fireEvent.keyDown(dialog, { key: 'Escape' })
+    await waitFor(() =>
+      expect(
+        screen.getByRole('button', { name: '删除对话 新对话' })
+      ).toHaveFocus()
+    )
+    expect(
+      screen.queryByRole('alertdialog', {
+        name: '确认永久删除对话 新对话'
+      })
+    ).not.toBeInTheDocument()
+
+    fireEvent.click(
+      screen.getByRole('button', { name: '删除对话 新对话' })
+    )
+    fireEvent.click(
+      screen.getByRole('button', {
+        name: '确认永久删除对话 新对话'
+      })
+    )
+    await waitFor(() =>
+      expect(
+        screen.queryByRole('alertdialog', {
+          name: '确认永久删除对话 新对话'
+        })
+      ).not.toBeInTheDocument()
+    )
+  })
+
+  it('keeps a conversation when cancelling its active task fails', async () => {
+    vi.mocked(api.agent.cancel).mockRejectedValueOnce(
+      new Error('cancel failed')
+    )
+    render(<App />)
+    const title = '取消失败时保留会话'
+
+    fireEvent.change(screen.getByLabelText('向 GoodBuddy 提问'), {
+      target: { value: title }
+    })
+    fireEvent.click(await screen.findByLabelText('发送'))
+    await waitFor(() => expect(run).toHaveBeenCalledOnce())
+
+    fireEvent.click(
+      await screen.findByLabelText(`更多会话操作 ${title}`)
+    )
+    fireEvent.click(
+      screen.getByRole('button', { name: `删除对话 ${title}` })
+    )
+    const confirm = screen.getByRole('button', {
+      name: `确认永久删除对话 ${title}`
+    })
+    fireEvent.click(confirm)
+
+    await waitFor(() =>
+      expect(api.agent.cancel).toHaveBeenCalledOnce()
+    )
+    expect(
+      await screen.findByText('停止会话中的运行任务失败，尚未删除对话')
+    ).toBeInTheDocument()
+    expect(
+      screen.getByRole('alertdialog', {
+        name: `确认永久删除对话 ${title}`
+      })
+    ).toBeInTheDocument()
+    await waitFor(() => expect(confirm).toBeEnabled())
+
+    vi.mocked(api.agent.cancel).mockResolvedValueOnce()
+    fireEvent.click(confirm)
+    await waitFor(() =>
+      expect(
+        screen.queryByRole('alertdialog', {
+          name: `确认永久删除对话 ${title}`
+        })
+      ).not.toBeInTheDocument()
+    )
+  })
+
   it('renders streamed reasoning, text, and tools in event order', async () => {
     render(<App />)
 
@@ -1426,7 +1543,9 @@ describe('App', () => {
 
     expect(composer).toHaveValue('尚未发送的草稿')
     expect(
-      screen.getAllByRole('button', { name: '删除对话 新对话' })
+      screen.getAllByRole('button', {
+        name: '更多会话操作 新对话'
+      })
     ).toHaveLength(1)
   })
 
@@ -1448,7 +1567,9 @@ describe('App', () => {
     })
 
     expect(
-      screen.getAllByRole('button', { name: /^删除对话/u })
+      screen.getAllByRole('button', {
+        name: /^更多会话操作/u
+      })
     ).toHaveLength(2)
   })
 
@@ -3478,7 +3599,7 @@ describe('App', () => {
       await screen.findByRole('heading', { name: '智能心跳' })
     ).toBeInTheDocument()
     expect(
-      screen.getByRole('tab', { name: '成长概览' })
+      await screen.findByRole('tab', { name: '成长概览' })
     ).toBeInTheDocument()
     expect(
       screen.getByRole('button', { name: '配置智能心跳' })
@@ -3488,27 +3609,400 @@ describe('App', () => {
     ).not.toBeInTheDocument()
   })
 
-  it('opens Magic Notes as a scoped first-class workspace', async () => {
+  it('shows retryable page-local knowledge errors without an empty-state flash', async () => {
+    vi.mocked(api.knowledge.getSnapshot).mockRejectedValueOnce(
+      new Error('知识数据库暂时不可用')
+    )
+    render(<App />)
+
+    fireEvent.click(screen.getByRole('button', { name: '知识库' }))
+    expect(
+      await screen.findByText('知识库加载失败')
+    ).toBeInTheDocument()
+    expect(screen.getAllByText('知识数据库暂时不可用')).toHaveLength(1)
+    expect(screen.queryByText('建立第一个知识库')).not.toBeInTheDocument()
+
+    fireEvent.click(screen.getByRole('button', { name: '重试' }))
+    expect(
+      await screen.findByText('建立第一个知识库')
+    ).toBeInTheDocument()
+  })
+
+  it('retries the knowledge library whose selection failed', async () => {
+    const firstLibraryId = '11111111-1111-4111-8111-111111111111'
+    const secondLibraryId = '22222222-2222-4222-8222-222222222222'
+    const libraries = [
+      {
+        id: firstLibraryId,
+        name: '产品知识',
+        description: '',
+        storageMode: 'managed' as const,
+        graphEnabled: false,
+        graphStrategy: 'rules' as const,
+        sourceCount: 0,
+        documentCount: 0,
+        indexedDocumentCount: 0
+      },
+      {
+        id: secondLibraryId,
+        name: '工程知识',
+        description: '',
+        storageMode: 'managed' as const,
+        graphEnabled: false,
+        graphStrategy: 'rules' as const,
+        sourceCount: 0,
+        documentCount: 0,
+        indexedDocumentCount: 0
+      }
+    ]
+    const snapshot = {
+      libraries,
+      sources: [],
+      documents: [],
+      graphNodes: [],
+      graphRelations: [],
+      evidence: []
+    }
+    vi.mocked(api.knowledge.getSnapshot)
+      .mockResolvedValueOnce({
+        ...snapshot,
+        selectedLibraryId: firstLibraryId
+      })
+      .mockRejectedValueOnce(new Error('工程知识暂时不可用'))
+      .mockResolvedValueOnce({
+        ...snapshot,
+        selectedLibraryId: secondLibraryId
+      })
+    render(<App />)
+
+    fireEvent.click(screen.getByRole('button', { name: '知识库' }))
+    fireEvent.click(
+      await screen.findByRole('button', {
+        name: /^工程知识 0 个文档/u
+      })
+    )
+    expect(
+      await screen.findByText('知识库刷新失败')
+    ).toBeInTheDocument()
+
+    fireEvent.click(screen.getByRole('button', { name: '重试' }))
+    await waitFor(() =>
+      expect(api.knowledge.getSnapshot).toHaveBeenLastCalledWith(
+        secondLibraryId
+      )
+    )
+    expect(
+      screen.getByRole('button', {
+        name: /^工程知识 0 个文档/u
+      })
+    ).toHaveAttribute('aria-current', 'page')
+  })
+
+  it('shows retryable page-local heartbeat errors without first-time guidance', async () => {
+    vi.mocked(api.heartbeats.list).mockRejectedValue(
+      new Error('心跳数据库暂时不可用')
+    )
     render(<App />)
-    await screen.findByText('项目：默认项目')
 
     fireEvent.click(
-      screen.getByRole('button', { name: '魔法笔记' })
+      screen.getByRole('button', { name: '智能心跳' })
+    )
+    expect(
+      await screen.findByText('智能心跳加载失败')
+    ).toBeInTheDocument()
+    expect(
+      screen.queryByRole('button', { name: '配置智能心跳' })
+    ).not.toBeInTheDocument()
+
+    const retry = await screen.findByRole('button', { name: '重试' })
+    vi.mocked(api.heartbeats.list).mockResolvedValue([])
+    fireEvent.click(retry)
+    expect(
+      await screen.findByRole('button', { name: '配置智能心跳' })
+    ).toBeInTheDocument()
+  })
+
+  it('does not expose the previous project heartbeat after a switch fails', async () => {
+    const secondProject = {
+      ...project,
+      id: '00000000-0000-4000-8000-000000000102',
+      name: '第二项目',
+      rootPath: 'C:\\Second'
+    }
+    vi.mocked(api.projects.list).mockResolvedValueOnce([
+      project,
+      secondProject
+    ])
+    vi.mocked(api.heartbeats.list).mockResolvedValue([
+      {
+        id: '00000000-0000-4000-8000-000000000701',
+        projectId,
+        name: '旧项目心跳',
+        timezone: 'Asia/Shanghai',
+        recurrence: { type: 'daily', localTime: '09:00' },
+        enabled: true,
+        lookbackHours: 24,
+        retentionDays: 30,
+        nextRunAt: '2026-08-05T01:00:00.000Z',
+        createdAt: '2026-08-01T00:00:00.000Z',
+        updatedAt: '2026-08-01T00:00:00.000Z'
+      }
+    ])
+    render(<App />)
+
+    fireEvent.click(
+      screen.getByRole('button', { name: '智能心跳' })
+    )
+    fireEvent.click(
+      await screen.findByRole('tab', { name: '心跳计划' })
+    )
+    expect(await screen.findAllByText('旧项目心跳')).not.toHaveLength(0)
+    vi.mocked(api.heartbeats.list).mockRejectedValue(
+      new Error('第二项目心跳读取失败')
+    )
+    fireEvent.change(screen.getByLabelText('当前项目'), {
+      target: { value: secondProject.id }
+    })
+    fireEvent.click(
+      screen.getByRole('button', { name: '智能心跳' })
     )
 
     expect(
-      await screen.findByRole('heading', { name: '魔法笔记' })
+      await screen.findByText('智能心跳加载失败')
     ).toBeInTheDocument()
-    expect(screen.getByText('项目：默认项目')).toBeInTheDocument()
+    expect(screen.queryAllByText('旧项目心跳')).toHaveLength(0)
     expect(
-      screen.getByRole('button', { name: '新建笔记' })
-    ).toBeInTheDocument()
-    expect(api.magicNotes.list).toHaveBeenCalled()
-    expect(
-      screen.queryByLabelText('切换助手工作栏')
+      screen.queryByRole('button', { name: '立即运行旧项目心跳' })
     ).not.toBeInTheDocument()
   })
 
+  it('automatically snapshots the conversation project on new activity', async () => {
+    render(<App />)
+    await screen.findByText('项目：默认项目')
+
+    fireEvent.change(screen.getByLabelText('向 GoodBuddy 提问'), {
+      target: { value: '记录项目范围' }
+    })
+    fireEvent.click(screen.getByLabelText('发送'))
+    await waitFor(() =>
+      expect(
+        loadActivityRecords().find(
+          (record) =>
+            record.kind === 'request' &&
+            record.title === '记录项目范围'
+        )?.scope
+      ).toEqual({
+        kind: 'project',
+        projectId,
+        projectName: project.name
+      })
+    )
+  })
+
+  it('marks the current primary navigation page and hides decorative icons', async () => {
+    render(<App />)
+
+    const navigation = screen.getByRole('navigation', {
+      name: '主导航'
+    })
+    const chat = within(navigation).getByRole('button', { name: '对话' })
+    const knowledge = within(navigation).getByRole('button', {
+      name: '知识库'
+    })
+
+    expect(chat).toHaveAttribute('aria-current', 'page')
+    expect(knowledge).not.toHaveAttribute('aria-current')
+    for (const button of within(navigation).getAllByRole('button')) {
+      expect(button.querySelector('svg')).toHaveAttribute(
+        'aria-hidden',
+        'true'
+      )
+    }
+
+    fireEvent.click(knowledge)
+    expect(knowledge).toHaveAttribute('aria-current', 'page')
+    expect(chat).not.toHaveAttribute('aria-current')
+  })
+
+  it('collapses the primary sidebar into an inert narrow-window overlay', async () => {
+    const originalWidth = window.innerWidth
+    const { container } = render(<App />)
+    const sidebar = container.querySelector<HTMLElement>('.sidebar')
+    const workspace = container.querySelector<HTMLElement>('.workspace')
+    expect(sidebar).not.toBeNull()
+    expect(workspace).not.toBeNull()
+    if (!sidebar || !workspace) {
+      return
+    }
+
+    try {
+      Object.defineProperty(window, 'innerWidth', {
+        configurable: true,
+        value: 680
+      })
+      window.dispatchEvent(new Event('resize'))
+
+      await waitFor(() =>
+        expect(sidebar).toHaveClass('sidebar--closed')
+      )
+      expect(sidebar).toHaveAttribute('aria-hidden', 'true')
+      expect(sidebar).toHaveAttribute('inert')
+
+      const toggle = screen.getByRole('button', { name: '切换侧栏' })
+      fireEvent.click(toggle)
+      expect(sidebar).not.toHaveClass('sidebar--closed')
+      expect(sidebar).toHaveAttribute('aria-hidden', 'false')
+      expect(sidebar).toHaveAttribute('aria-modal', 'true')
+      expect(sidebar).not.toHaveAttribute('inert')
+      expect(workspace).toHaveAttribute('aria-hidden', 'true')
+      expect(workspace).toHaveAttribute('inert')
+      await waitFor(() =>
+        expect(
+          within(sidebar).getByRole('button', { name: '对话' })
+        ).toHaveFocus()
+      )
+
+      fireEvent.click(
+        screen.getByRole('button', { name: '关闭侧栏' })
+      )
+      await waitFor(() => expect(toggle).toHaveFocus())
+      expect(sidebar).toHaveClass('sidebar--closed')
+      expect(workspace).not.toHaveAttribute('aria-hidden')
+      expect(workspace).not.toHaveAttribute('inert')
+    } finally {
+      Object.defineProperty(window, 'innerWidth', {
+        configurable: true,
+        value: originalWidth
+      })
+    }
+  })
+
+  it('opens Magic Notes as a scoped first-class workspace', async () => {
+    api.updates = {
+      getSettings: vi.fn(async () => ({
+        checkUpdatesOnStartup: false,
+        magicNotesEnabled: true
+      })),
+      updateSettings: vi.fn(async () => ({
+        checkUpdatesOnStartup: false,
+        magicNotesEnabled: true
+      })),
+      check: vi.fn(),
+      openReleasePage: vi.fn(async () => {}),
+      onResult: vi.fn(() => () => {})
+    }
+    try {
+      render(<App />)
+      await screen.findByText('项目：默认项目')
+      const magicNotesEntry = await screen.findByRole('button', {
+        name: '魔法笔记'
+      })
+
+      fireEvent.click(magicNotesEntry)
+
+      expect(
+        await screen.findByRole('heading', { name: '魔法笔记' })
+      ).toBeInTheDocument()
+      expect(screen.getByText('项目：默认项目')).toBeInTheDocument()
+      expect(
+        screen.getByRole('button', { name: '新建笔记' })
+      ).toBeInTheDocument()
+      expect(api.magicNotes.list).toHaveBeenCalled()
+      expect(
+        screen.queryByLabelText('切换助手工作栏')
+      ).not.toBeInTheDocument()
+    } finally {
+      delete api.updates
+    }
+  })
+
+  it('hides Magic Notes when the platform feature is disabled', async () => {
+    api.updates = {
+      getSettings: vi.fn(async () => ({
+        checkUpdatesOnStartup: false,
+        magicNotesEnabled: false
+      })),
+      updateSettings: vi.fn(async () => ({
+        checkUpdatesOnStartup: false,
+        magicNotesEnabled: false
+      })),
+      check: vi.fn(),
+      openReleasePage: vi.fn(async () => {}),
+      onResult: vi.fn(() => () => {})
+    }
+    try {
+      render(<App />)
+      await waitFor(() =>
+        expect(
+          screen.queryByRole('button', { name: '魔法笔记' })
+        ).not.toBeInTheDocument()
+      )
+    } finally {
+      delete api.updates
+    }
+  })
+
+  it('hides Magic Notes by default without an explicit setting', () => {
+    render(<App />)
+
+    expect(
+      screen.queryByRole('button', { name: '魔法笔记' })
+    ).not.toBeInTheDocument()
+  })
+
+  it('keeps platform-feature switches in Settings without navigating', async () => {
+    let applicationSettings = {
+      checkUpdatesOnStartup: false,
+      magicNotesEnabled: false
+    }
+    api.updates = {
+      getSettings: vi.fn(async () => ({ ...applicationSettings })),
+      updateSettings: vi.fn(async (input) => {
+        applicationSettings = {
+          ...applicationSettings,
+          ...input
+        }
+        return { ...applicationSettings }
+      }),
+      check: vi.fn(),
+      openReleasePage: vi.fn(async () => {}),
+      onResult: vi.fn(() => () => {})
+    }
+    try {
+      const { container } = render(<App />)
+      fireEvent.click(await screen.findByText('本地工作区'))
+      fireEvent.click(
+        screen.getByRole('tab', { name: '平台功能' })
+      )
+      const toggle = await screen.findByRole('switch', {
+        name: '显示魔法笔记入口'
+      })
+
+      fireEvent.click(toggle)
+      await waitFor(() => expect(toggle).toBeChecked())
+      expect(
+        screen.getByRole('heading', { name: '设置中心' })
+      ).toBeInTheDocument()
+      expect(
+        screen.getByRole('button', { name: '魔法笔记' })
+      ).toBeInTheDocument()
+      expect(
+        container.querySelector('.magic-notes-page')
+      ).not.toBeInTheDocument()
+
+      fireEvent.click(toggle)
+      await waitFor(() => expect(toggle).not.toBeChecked())
+      expect(
+        screen.getByRole('heading', { name: '设置中心' })
+      ).toBeInTheDocument()
+      expect(
+        screen.queryByRole('button', { name: '魔法笔记' })
+      ).not.toBeInTheDocument()
+    } finally {
+      delete api.updates
+    }
+  })
+
   it('gives the knowledge workspace the full content width', async () => {
     render(<App />)
 
diff --git a/src/renderer/src/App.tsx b/src/renderer/src/App.tsx
index ac3cbe4..1e66a6d 100644
--- a/src/renderer/src/App.tsx
+++ b/src/renderer/src/App.tsx
@@ -104,6 +104,7 @@ import { HeartbeatCenter } from './HeartbeatCenter'
 import { MagicNotesWorkspace } from './MagicNotesWorkspace'
 import { MarkdownRenderer } from './MarkdownRenderer'
 import {
+  DestructiveConfirmActions,
   EmptyState,
   PageShell,
   ScopeBadge
@@ -609,6 +610,19 @@ function createConversation(
   }
 }
 
+function displayErrorMessage(reason: unknown, fallback: string): string {
+  if (
+    typeof reason === 'object' &&
+    reason !== null &&
+    'message' in reason &&
+    typeof reason.message === 'string' &&
+    reason.message
+  ) {
+    return reason.message
+  }
+  return fallback
+}
+
 function isUnusedConversation(conversation: Conversation): boolean {
   return (
     conversation.title === '新对话' &&
@@ -1030,6 +1044,7 @@ function App(): React.JSX.Element {
     useState(false)
   const migrationConversations = useRef(conversations)
   const [projects, setProjects] = useState<AssistantProject[]>([])
+  const projectsRef = useRef(projects)
   const [assistantTasks, setAssistantTasks] = useState<AssistantTask[]>([])
   const [tokenUsage, setTokenUsage] =
     useState<TokenUsageSummary>(emptyTokenUsage)
@@ -1060,6 +1075,8 @@ function App(): React.JSX.Element {
   const [heartbeatRuns, setHeartbeatRuns] = useState<
     AssistantHeartbeatRun[]
   >([])
+  const [heartbeatLoading, setHeartbeatLoading] = useState(true)
+  const [heartbeatLoadError, setHeartbeatLoadError] = useState<string>()
   const [assistantExperts, setAssistantExperts] = useState<
     AssistantExpert[]
   >([])
@@ -1110,7 +1127,12 @@ function App(): React.JSX.Element {
       ? 'ask'
       : workMode
   const [appInfo, setAppInfo] = useState<AppInfo>()
-  const [sidebarOpen, setSidebarOpen] = useState(true)
+  const [narrowWindow, setNarrowWindow] = useState(
+    () => window.innerWidth < 900
+  )
+  const [sidebarOpen, setSidebarOpen] = useState(
+    () => window.innerWidth >= 900
+  )
   const [assistantSidebarOpen, setAssistantSidebarOpen] = useState(
     () => window.innerWidth >= 1280
   )
@@ -1120,8 +1142,13 @@ function App(): React.JSX.Element {
     Record<string, BrowserLiveState>
   >({})
   const [view, setView] = useState<WorkspaceView>('chat')
+  const [magicNotesEnabled, setMagicNotesEnabled] = useState(false)
   const [searchQuery, setSearchQuery] = useState('')
   const [conversationActionsId, setConversationActionsId] = useState('')
+  const [confirmingConversationId, setConfirmingConversationId] =
+    useState('')
+  const [deletingConversationId, setDeletingConversationId] =
+    useState('')
   const [renamingConversationId, setRenamingConversationId] = useState('')
   const [notifications, notify] = useReducer(
     appNotificationReducer,
@@ -1169,6 +1196,11 @@ function App(): React.JSX.Element {
     evidence: []
   })
   const [knowledgeLoading, setKnowledgeLoading] = useState(true)
+  const [knowledgeLoadError, setKnowledgeLoadError] = useState<string>()
+  const knowledgeLoadRequestRef = useRef(0)
+  const failedKnowledgeLibraryIdRef = useRef<string | undefined>(
+    undefined
+  )
   const [enabledKnowledgeLibraryIds, setEnabledKnowledgeLibraryIds] = useState<
     string[]
   >([])
@@ -1182,20 +1214,67 @@ function App(): React.JSX.Element {
   const knowledgeScopeInitialized = useRef(false)
   const inputRef = useRef<HTMLTextAreaElement>(null)
   const scrollRef = useRef<HTMLDivElement>(null)
+  const sidebarRef = useRef<HTMLElement>(null)
+  const sidebarToggleRef = useRef<HTMLButtonElement>(null)
   const topbarMenuRef = useRef<HTMLDivElement>(null)
   const topbarMenuTriggerRef = useRef<HTMLButtonElement>(null)
   const conversationActionTriggerRefs = useRef(
     new Map<string, HTMLButtonElement>()
   )
+  const closeNarrowSidebar = useCallback((): void => {
+    setSidebarOpen(false)
+    requestAnimationFrame(() => sidebarToggleRef.current?.focus())
+  }, [])
 
   useEffect(() => {
     activeConversationIdRef.current = activeId
   }, [activeId])
 
+  useEffect(() => {
+    const collapseSidebarAtNarrowWidth = (): void => {
+      const narrow = window.innerWidth < 900
+      setNarrowWindow(narrow)
+      if (narrow) {
+        setSidebarOpen(false)
+      }
+    }
+    window.addEventListener('resize', collapseSidebarAtNarrowWidth)
+    return () =>
+      window.removeEventListener('resize', collapseSidebarAtNarrowWidth)
+  }, [])
+
+  useEffect(() => {
+    if (!narrowWindow || !sidebarOpen) {
+      return
+    }
+    const focusFrame = requestAnimationFrame(() => {
+      sidebarRef.current
+        ?.querySelector<HTMLButtonElement>(
+          '.primary-nav button[aria-current="page"], .primary-nav button'
+        )
+        ?.focus()
+    })
+    const closeOnEscape = (event: KeyboardEvent): void => {
+      if (event.key === 'Escape') {
+        event.preventDefault()
+        closeNarrowSidebar()
+      }
+    }
+    document.addEventListener('keydown', closeOnEscape)
+    return () => {
+      cancelAnimationFrame(focusFrame)
+      document.removeEventListener('keydown', closeOnEscape)
+    }
+  }, [closeNarrowSidebar, narrowWindow, sidebarOpen])
+
   useEffect(() => {
     conversationsRef.current = conversations
   }, [conversations])
 
+  useEffect(() => {
+    projectsRef.current = projects
+  }, [projects])
+
   useEffect(() => {
     resizeComposerTextarea(inputRef.current)
   }, [input])
@@ -1272,6 +1351,10 @@ function App(): React.JSX.Element {
     void updates
       .getSettings()
       .then(async (settings) => {
+        setMagicNotesEnabled(settings.magicNotesEnabled)
+        if (!settings.magicNotesEnabled) {
+          setView('chat')
+        }
         if (!settings.checkUpdatesOnStartup) {
           return
         }
@@ -1712,10 +1795,35 @@ function App(): React.JSX.Element {
   )
 
   const recordActivity = useCallback(
-    (record: Omit<ActivityRecord, 'id' | 'createdAt'>): void => {
+    (
+      record: Omit<ActivityRecord, 'id' | 'createdAt' | 'scope'>,
+      scopeOverride?: ActivityRecord['scope']
+    ): void => {
+      const conversation = conversationsRef.current.find(
+        (candidate) => candidate.id === record.conversationId
+      )
+      const project = conversation?.projectId
+        ? projectsRef.current.find(
+            (candidate) => candidate.id === conversation.projectId
+          )
+        : undefined
+      const scope: ActivityRecord['scope'] =
+        scopeOverride ??
+        (!conversation
+          ? { kind: 'unavailable' }
+          : !conversation.projectId
+            ? { kind: 'global' }
+            : project?.id && project.name
+              ? {
+                  kind: 'project',
+                  projectId: project.id.slice(0, 256),
+                  projectName: project.name.slice(0, 120)
+                }
+              : { kind: 'unavailable' })
       setActivityRecords((current) =>
         upsertActivityRecord(current, {
           ...record,
+          scope,
           id: crypto.randomUUID(),
           createdAt: Date.now()
         })
@@ -1758,39 +1866,76 @@ function App(): React.JSX.Element {
           activity.detail
         )
       }
-      recordActivity({
-        requestId: activity.requestId,
-        conversationId: activity.conversationId,
-        callId: activity.callId,
-        kind: activity.kind,
-        title: activity.title,
-        detail: activity.detail,
-        status: activity.status
-      })
+      recordActivity(
+        {
+          requestId: activity.requestId,
+          conversationId: activity.conversationId,
+          callId: activity.callId,
+          kind: activity.kind,
+          title: activity.title,
+          detail: activity.detail,
+          status: activity.status
+        },
+        {
+          kind: 'project',
+          projectId: activity.projectId.slice(0, 256),
+          projectName: activity.projectName.slice(0, 120)
+        }
+      )
     })
   }, [recordActivity, updateRequestActivity])
 
   const refreshKnowledge = useCallback(
     async (libraryId?: string): Promise<KnowledgeSnapshot> => {
-      const snapshot = await window.goodbuddy.knowledge.getSnapshot(libraryId)
-      setKnowledgeSnapshot(snapshot)
-      if (!knowledgeScopeInitialized.current) {
-        knowledgeScopeInitialized.current = true
-        setEnabledKnowledgeLibraryIds(
-          snapshot.libraries.map((library) => library.id)
-        )
-      } else {
-        setEnabledKnowledgeLibraryIds((current) =>
-          current.filter((id) =>
-            snapshot.libraries.some((library) => library.id === id)
+      const requestId = ++knowledgeLoadRequestRef.current
+      try {
+        const snapshot =
+          await window.goodbuddy.knowledge.getSnapshot(libraryId)
+        if (requestId !== knowledgeLoadRequestRef.current) {
+          return snapshot
+        }
+        failedKnowledgeLibraryIdRef.current = undefined
+        setKnowledgeSnapshot(snapshot)
+        setKnowledgeLoadError(undefined)
+        if (!knowledgeScopeInitialized.current) {
+          knowledgeScopeInitialized.current = true
+          setEnabledKnowledgeLibraryIds(
+            snapshot.libraries.map((library) => library.id)
           )
+        } else {
+          setEnabledKnowledgeLibraryIds((current) =>
+            current.filter((id) =>
+              snapshot.libraries.some((library) => library.id === id)
+            )
+          )
+        }
+        return snapshot
+      } catch (reason) {
+        if (requestId !== knowledgeLoadRequestRef.current) {
+          throw reason
+        }
+        failedKnowledgeLibraryIdRef.current = libraryId
+        setKnowledgeLoadError(
+          displayErrorMessage(reason, '本地知识库读取失败')
         )
+        throw reason
       }
-      return snapshot
     },
     []
   )
 
+  const retryKnowledgeLoad = useCallback(async (): Promise<void> => {
+    setKnowledgeLoading(true)
+    setKnowledgeLoadError(undefined)
+    try {
+      await refreshKnowledge(failedKnowledgeLibraryIdRef.current)
+    } catch {
+      // The recoverable page state is set by refreshKnowledge.
+    } finally {
+      setKnowledgeLoading(false)
+    }
+  }, [refreshKnowledge])
+
   const switchRuntime = useCallback(
     async (selection: AgentRuntimeSelection): Promise<void> => {
       if (!runtimeSettings || !activeConversation || runtimeSwitching) {
@@ -2610,19 +2755,41 @@ function App(): React.JSX.Element {
 
   useEffect(() => {
     const requestId = ++heartbeatLoadRequestRef.current
-    void loadHeartbeats()
-      .then((result) => {
-        if (requestId !== heartbeatLoadRequestRef.current) {
-          return
-        }
-        setAssistantHeartbeats(result.configs)
-        setHeartbeatRuns(result.runs)
-        setHeartbeatEntries(result.entries)
-      })
-      .catch(() =>
-        notify({ tone: 'error', message: '智能心跳读取失败' })
-      )
+    const timeout = setTimeout(() => {
+      if (requestId !== heartbeatLoadRequestRef.current) {
+        return
+      }
+      setHeartbeatLoading(true)
+      setHeartbeatLoadError(undefined)
+      setAssistantHeartbeats([])
+      setHeartbeatRuns([])
+      setHeartbeatEntries([])
+      void loadHeartbeats()
+        .then((result) => {
+          if (requestId !== heartbeatLoadRequestRef.current) {
+            return
+          }
+          setAssistantHeartbeats(result.configs)
+          setHeartbeatRuns(result.runs)
+          setHeartbeatEntries(result.entries)
+          setHeartbeatLoadError(undefined)
+        })
+        .catch((reason: unknown) => {
+          if (requestId !== heartbeatLoadRequestRef.current) {
+            return
+          }
+          setHeartbeatLoadError(
+            displayErrorMessage(reason, '智能心跳读取失败')
+          )
+        })
+        .finally(() => {
+          if (requestId === heartbeatLoadRequestRef.current) {
+            setHeartbeatLoading(false)
+          }
+        })
+    }, 0)
     return () => {
+      clearTimeout(timeout)
       if (requestId === heartbeatLoadRequestRef.current) {
         heartbeatLoadRequestRef.current += 1
       }
@@ -2647,6 +2814,21 @@ function App(): React.JSX.Element {
     )
   }, [activeProjectId, refreshHeartbeats])
 
+  const retryHeartbeatLoad = useCallback(async (): Promise<void> => {
+    setHeartbeatLoading(true)
+    setHeartbeatLoadError(undefined)
+    try {
+      await refreshHeartbeatCenter()
+      setHeartbeatLoadError(undefined)
+    } catch (reason) {
+      setHeartbeatLoadError(
+        displayErrorMessage(reason, '智能心跳读取失败')
+      )
+    } finally {
+      setHeartbeatLoading(false)
+    }
+  }, [refreshHeartbeatCenter])
+
   const createHeartbeat = useCallback(
     async (input: HeartbeatCreateInput): Promise<void> => {
       const projectId = activeProjectId
@@ -2706,8 +2888,11 @@ function App(): React.JSX.Element {
       }
       refreshing = true
       void refreshHeartbeatCenter()
-        .catch(() =>
-          notify({ tone: 'error', message: '智能心跳刷新失败' })
+        .then(() => setHeartbeatLoadError(undefined))
+        .catch((reason: unknown) =>
+          setHeartbeatLoadError(
+            displayErrorMessage(reason, '智能心跳刷新失败')
+          )
         )
         .finally(() => {
           refreshing = false
@@ -2806,14 +2991,8 @@ function App(): React.JSX.Element {
   useEffect(() => {
     const timeout = setTimeout(() => {
       void refreshKnowledge()
-        .catch((reason: unknown) => {
-          notify({
-            tone: 'error',
-            message:
-              reason instanceof Error
-                ? reason.message
-                : '本地知识库读取失败'
-          })
+        .catch(() => {
+          // refreshKnowledge exposes a recoverable page-local error.
         })
         .finally(() => setKnowledgeLoading(false))
     }, 0)
@@ -3137,19 +3316,38 @@ function App(): React.JSX.Element {
     )
   }
 
-  const deleteConversation = (conversationId: string): void => {
+  const deleteConversation = async (
+    conversationId: string
+  ): Promise<void> => {
+    if (deletingConversationId) {
+      return
+    }
+    setDeletingConversationId(conversationId)
+    const activeRequests = [...activeRuns.current.entries()]
+      .filter(([, run]) => run.conversationId === conversationId)
+      .map(([requestId]) => requestId)
+    try {
+      await Promise.all(
+        activeRequests.map((requestId) =>
+          window.goodbuddy.agent.cancel(requestId)
+        )
+      )
+    } catch {
+      notify({
+        tone: 'error',
+        message: '停止会话中的运行任务失败，尚未删除对话'
+      })
+      setDeletingConversationId('')
+      return
+    }
+    setConfirmingConversationId('')
+    setDeletingConversationId('')
     if (conversationActionsId === conversationId) {
       setConversationActionsId('')
     }
     if (renamingConversationId === conversationId) {
       setRenamingConversationId('')
     }
-    const activeRequest = [...activeRuns.current.entries()].find(
-      ([, run]) => run.conversationId === conversationId
-    )?.[0]
-    if (activeRequest) {
-      void window.goodbuddy.agent.cancel(activeRequest)
-    }
     const browserStop = window.goodbuddy.browser?.stop(conversationId)
     if (browserStop) {
       void browserStop.catch(() => {
@@ -3972,7 +4170,15 @@ function App(): React.JSX.Element {
 
   return (
     <div className="app-shell">
-      <aside className={sidebarOpen ? 'sidebar' : 'sidebar sidebar--closed'}>
+      <aside
+        aria-label={narrowWindow && sidebarOpen ? '主侧栏' : undefined}
+        aria-hidden={!sidebarOpen}
+        aria-modal={narrowWindow && sidebarOpen ? 'true' : undefined}
+        className={sidebarOpen ? 'sidebar' : 'sidebar sidebar--closed'}
+        inert={!sidebarOpen}
+        ref={sidebarRef}
+        role={narrowWindow && sidebarOpen ? 'dialog' : undefined}
+      >
         <div className="brand">
           <div className="brand__mark">
             <img
@@ -4028,28 +4234,33 @@ function App(): React.JSX.Element {
 
         <nav className="primary-nav" aria-label="主导航">
           <button
+            aria-current={view === 'chat' ? 'page' : undefined}
             className={
               view === 'chat' ? 'nav-item nav-item--active' : 'nav-item'
             }
             onClick={() => setView('chat')}
             type="button"
           >
-            <MessageSquare size={17} />
+            <MessageSquare aria-hidden="true" size={17} />
             <span>对话</span>
           </button>
+          {magicNotesEnabled && (
+            <button
+              aria-current={view === 'magic-notes' ? 'page' : undefined}
+              className={
+                view === 'magic-notes'
+                  ? 'nav-item nav-item--active'
+                  : 'nav-item'
+              }
+              onClick={() => setView('magic-notes')}
+              type="button"
+            >
+              <Sparkles aria-hidden="true" size={17} />
+              <span>魔法笔记</span>
+            </button>
+          )}
           <button
-            className={
-              view === 'magic-notes'
-                ? 'nav-item nav-item--active'
-                : 'nav-item'
-            }
-            onClick={() => setView('magic-notes')}
-            type="button"
-          >
-            <Sparkles size={17} />
-            <span>魔法笔记</span>
-          </button>
-          <button
+            aria-current={view === 'knowledge' ? 'page' : undefined}
             className={
               view === 'knowledge'
                 ? 'nav-item nav-item--active'
@@ -4058,10 +4269,11 @@ function App(): React.JSX.Element {
             onClick={() => setView('knowledge')}
             type="button"
           >
-            <Library size={17} />
+            <Library aria-hidden="true" size={17} />
             <span>知识库</span>
           </button>
           <button
+            aria-current={view === 'heartbeat' ? 'page' : undefined}
             className={
               view === 'heartbeat'
                 ? 'nav-item nav-item--active'
@@ -4070,7 +4282,7 @@ function App(): React.JSX.Element {
             onClick={() => setView('heartbeat')}
             type="button"
           >
-            <HeartPulse size={17} />
+            <HeartPulse aria-hidden="true" size={17} />
             <span>智能心跳</span>
             {pendingHeartbeatSuggestionCount > 0 && (
               <span
@@ -4082,6 +4294,7 @@ function App(): React.JSX.Element {
             )}
           </button>
           <button
+            aria-current={view === 'activity' ? 'page' : undefined}
             className={
               view === 'activity'
                 ? 'nav-item nav-item--active'
@@ -4090,7 +4303,7 @@ function App(): React.JSX.Element {
             onClick={() => setView('activity')}
             type="button"
           >
-            <TerminalSquare size={17} />
+            <TerminalSquare aria-hidden="true" size={17} />
             <span>任务与活动</span>
           </button>
         </nav>
@@ -4157,6 +4370,7 @@ function App(): React.JSX.Element {
                   className="conversation-more"
                   onClick={() => {
                     setRenamingConversationId('')
+                    setConfirmingConversationId('')
                     setConversationActionsId((current) =>
                       current === conversation.id ? '' : conversation.id
                     )
@@ -4177,16 +4391,6 @@ function App(): React.JSX.Element {
                 >
                   <MoreHorizontal size={14} />
                 </button>
-                {!conversation.remote && (
-                  <button
-                    aria-label={`删除对话 ${conversation.title}`}
-                    className="conversation-delete"
-                    onClick={() => deleteConversation(conversation.id)}
-                    type="button"
-                  >
-                    <Trash2 size={14} />
-                  </button>
-                )}
               </div>
               {conversationActionsId === conversation.id && (
                 <div
@@ -4229,6 +4433,30 @@ function App(): React.JSX.Element {
                     <Download size={14} />
                     导出 Markdown
                   </button>
+                  {!conversation.remote && (
+                    <DestructiveConfirmActions
+                      cancelAriaLabel={`取消删除对话 ${conversation.title}`}
+                      confirmAriaLabel={`确认永久删除对话 ${conversation.title}`}
+                      confirmLabel="永久删除对话"
+                      confirming={
+                        confirmingConversationId === conversation.id
+                      }
+                      disabled={
+                        deletingConversationId === conversation.id
+                      }
+                      icon={<Trash2 aria-hidden="true" size={14} />}
+                      message="将永久删除此会话的全部内容；如果此会话有正在运行的任务，也会同时停止。此操作不可恢复。"
+                      onCancel={() => setConfirmingConversationId('')}
+                      onConfirm={() =>
+                        void deleteConversation(conversation.id)
+                      }
+                      onRequestConfirm={() =>
+                        setConfirmingConversationId(conversation.id)
+                      }
+                      triggerAriaLabel={`删除对话 ${conversation.title}`}
+                      triggerLabel="删除对话"
+                    />
+                  )}
                 </div>
               )}
               {!conversation.remote &&
@@ -4304,16 +4532,29 @@ function App(): React.JSX.Element {
           </button>
         </div>
       </aside>
+      {sidebarOpen && (
+        <button
+          aria-label="关闭侧栏"
+          className="sidebar-backdrop"
+          onClick={closeNarrowSidebar}
+          type="button"
+        />
+      )}
 
-      <main className="workspace">
+      <main
+        aria-hidden={narrowWindow && sidebarOpen ? 'true' : undefined}
+        className="workspace"
+        inert={narrowWindow && sidebarOpen}
+      >
         <header className="topbar">
           <button
             className="icon-button sidebar-toggle"
             type="button"
             aria-label="切换侧栏"
             onClick={() => setSidebarOpen((open) => !open)}
+            ref={sidebarToggleRef}
           >
-            <PanelLeft size={18} />
+            <PanelLeft aria-hidden="true" size={18} />
           </button>
           {view === 'chat' && (
             <>
@@ -5496,7 +5737,7 @@ function App(): React.JSX.Element {
           )}
             </footer>
           </PageShell>
-        ) : view === 'magic-notes' ? (
+        ) : view === 'magic-notes' && magicNotesEnabled ? (
           <PageShell variant="master-detail">
             <MagicNotesWorkspace
               key={activeProject?.id ?? 'global'}
@@ -5513,6 +5754,7 @@ function App(): React.JSX.Element {
               graphNodes={knowledgeSnapshot.graphNodes}
               graphRelations={knowledgeSnapshot.graphRelations}
               libraries={knowledgeSnapshot.libraries}
+              loadError={knowledgeLoadError}
               loading={knowledgeLoading}
               onCreateLibrary={createKnowledgeLibrary}
               onCreateEntity={async (input) => {
@@ -5629,8 +5871,11 @@ function App(): React.JSX.Element {
                   window.goodbuddy.knowledge.retrySource(sourceId)
                 )
               }
+              onRetryLoad={retryKnowledgeLoad}
               onSelectLibrary={(libraryId) => {
-                void refreshKnowledge(libraryId)
+                void refreshKnowledge(libraryId).catch(() => {
+                  // KnowledgeWorkspace renders the recoverable load error.
+                })
               }}
               onSyncSource={(sourceId) =>
                 runKnowledgeSourceAction(() =>
@@ -5660,9 +5905,12 @@ function App(): React.JSX.Element {
               configs={assistantHeartbeats}
               currentProjectName={activeProject?.name}
               entries={heartbeatEntries}
+              loadError={heartbeatLoadError}
+              loading={heartbeatLoading}
               memories={assistantMemories}
               onCreate={createHeartbeat}
-              onRefresh={refreshHeartbeatCenter}
+              onRefresh={retryHeartbeatLoad}
+              onRetryLoad={retryHeartbeatLoad}
               onRemove={removeHeartbeat}
               onRunNow={runHeartbeat}
               onSetMemoryStatus={setMemoryStatus}
@@ -5694,6 +5942,9 @@ function App(): React.JSX.Element {
                 setSelectedExpertId('')
               }
             }}
+            onMagicNotesEnabledChange={(enabled) => {
+              setMagicNotesEnabled(enabled)
+            }}
             onRemoveHeartbeat={removeHeartbeat}
             onRunHeartbeat={runHeartbeat}
             onNotify={notify}
diff --git a/src/renderer/src/HeartbeatCenter.test.tsx b/src/renderer/src/HeartbeatCenter.test.tsx
index 3d47f5d..60068be 100644
--- a/src/renderer/src/HeartbeatCenter.test.tsx
+++ b/src/renderer/src/HeartbeatCenter.test.tsx
@@ -110,6 +110,7 @@ function createProps(
     onRemove: vi.fn(async () => {}),
     onRunNow: vi.fn(async () => {}),
     onRefresh: vi.fn(async () => {}),
+    onRetryLoad: vi.fn(async () => {}),
     onSetMemoryStatus: vi.fn(async () => {}),
     onSetTaskStatus: vi.fn(async () => {}),
     onUseFollowUpTask: vi.fn(),
@@ -264,4 +265,56 @@ describe('HeartbeatCenter', () => {
       screen.getByRole('button', { name: '启用智能心跳' })
     ).toBeInTheDocument()
   })
+
+  it('keeps loading and load failure distinct from first-time empty state', () => {
+    const emptyProps = {
+      configs: [],
+      runs: [],
+      entries: [],
+      memories: [],
+      tasks: []
+    }
+    const { rerender } = render(
+      <HeartbeatCenter
+        {...createProps({
+          ...emptyProps,
+          loading: true
+        })}
+      />
+    )
+
+    expect(screen.getByText('正在加载智能心跳')).toBeInTheDocument()
+    expect(
+      screen.queryByRole('button', { name: '配置智能心跳' })
+    ).not.toBeInTheDocument()
+
+    rerender(
+      <HeartbeatCenter
+        {...createProps({
+          ...emptyProps,
+          loadError: '数据库暂时不可用'
+        })}
+      />
+    )
+    expect(screen.getByText('智能心跳加载失败')).toBeInTheDocument()
+    expect(screen.getByText('数据库暂时不可用')).toBeInTheDocument()
+    expect(
+      screen.queryByRole('button', { name: '配置智能心跳' })
+    ).not.toBeInTheDocument()
+    expect(screen.getByRole('button', { name: '重试' })).toBeInTheDocument()
+  })
+
+  it('keeps existing heartbeat data visible when refresh fails', () => {
+    render(
+      <HeartbeatCenter
+        {...createProps({ loadError: '刷新连接失败' })}
+      />
+    )
+
+    expect(screen.getByText('智能心跳刷新失败')).toBeInTheDocument()
+    expect(screen.getByText(config.name)).toBeInTheDocument()
+    expect(
+      screen.getByText(entry.summary)
+    ).toBeInTheDocument()
+  })
 })
diff --git a/src/renderer/src/HeartbeatCenter.tsx b/src/renderer/src/HeartbeatCenter.tsx
index 374397e..b200a51 100644
--- a/src/renderer/src/HeartbeatCenter.tsx
+++ b/src/renderer/src/HeartbeatCenter.tsx
@@ -54,6 +54,9 @@ export type HeartbeatCenterProps = {
   ) => Promise<void>
   onUseFollowUpTask: (task: AssistantTask) => void
   currentProjectName?: string
+  loading?: boolean
+  loadError?: string
+  onRetryLoad: () => void | Promise<void>
 }
 
 const dateTimeFormatter = new Intl.DateTimeFormat('zh-CN', {
@@ -143,7 +146,10 @@ export function HeartbeatCenter({
   onSetMemoryStatus,
   onSetTaskStatus,
   onUseFollowUpTask,
-  currentProjectName = '当前项目'
+  currentProjectName = '当前项目',
+  loading = false,
+  loadError,
+  onRetryLoad
 }: HeartbeatCenterProps): React.JSX.Element {
   const [tab, setTab] = useState<HeartbeatCenterTab>('overview')
   const [pendingAction, setPendingAction] = useState<string>()
@@ -226,6 +232,10 @@ export function HeartbeatCenter({
         entry.followUpTaskIds.length
     )
   )
+  const hasHeartbeatData =
+    configs.length > 0 || runs.length > 0 || entries.length > 0
+  const initialLoadBlocked =
+    !hasHeartbeatData && (loading || loadError !== undefined)
 
   const runAction = async (
     actionId: string,
@@ -269,11 +279,12 @@ export function HeartbeatCenter({
     >
       <PageHeader
         actions={
-          <>
+          initialLoadBlocked ? undefined : (
+            <>
             <button
               aria-label="刷新智能心跳"
               className="secondary-button"
-              disabled={pendingAction !== undefined}
+              disabled={loading || pendingAction !== undefined}
               onClick={() => void runAction('refresh', onRefresh)}
               type="button"
             >
@@ -283,7 +294,7 @@ export function HeartbeatCenter({
             {primaryConfig ? (
               <button
                 className="primary-button"
-                disabled={pendingAction !== undefined}
+                disabled={loading || pendingAction !== undefined}
                 onClick={() =>
                   void runAction(`run:${primaryConfig.id}`, () =>
                     onRunNow(primaryConfig.id)
@@ -299,13 +310,15 @@ export function HeartbeatCenter({
             ) : (
               <button
                 className="primary-button"
+                disabled={loading}
                 onClick={() => setTab('plans')}
                 type="button"
               >
                 配置智能心跳
               </button>
             )}
-          </>
+            </>
+          )
         }
         description="定期回顾经历、沉淀记忆、发现问题，并把每次变化转化为可处理的成长建议。"
         eyebrow="SMART HEARTBEAT"
@@ -321,6 +334,49 @@ export function HeartbeatCenter({
         </p>
       )}
 
+      {loading && !hasHeartbeatData ? (
+        <EmptyState
+          description="正在读取心跳计划、运行记录和成长报告。"
+          icon={<RefreshCw size={24} />}
+          level="page"
+          title="正在加载智能心跳"
+        />
+      ) : loadError && !hasHeartbeatData ? (
+        <EmptyState
+          action={
+            <button
+              className="secondary-button"
+              onClick={() => void onRetryLoad()}
+              type="button"
+            >
+              <RefreshCw aria-hidden="true" size={14} />
+              重试
+            </button>
+          }
+          description={loadError}
+          icon={<XCircle size={24} />}
+          level="page"
+          title="智能心跳加载失败"
+        />
+      ) : null}
+
+      {loadError && hasHeartbeatData && (
+        <div className="heartbeat-center__error" role="alert">
+          <strong>智能心跳刷新失败</strong>
+          <p>{loadError}</p>
+          <button
+            className="secondary-button"
+            onClick={() => void onRetryLoad()}
+            type="button"
+          >
+            <RefreshCw aria-hidden="true" size={14} />
+            重试
+          </button>
+        </div>
+      )}
+
+      {!initialLoadBlocked && (
+        <>
       <PageTabs
         ariaLabel="智能心跳视图"
         idPrefix="heartbeat"
@@ -1034,6 +1090,8 @@ export function HeartbeatCenter({
           />
         </div>
       )}
+        </>
+      )}
     </section>
   )
 }
diff --git a/src/renderer/src/KnowledgeWorkspace.test.tsx b/src/renderer/src/KnowledgeWorkspace.test.tsx
index 6a6952e..f9e5e80 100644
--- a/src/renderer/src/KnowledgeWorkspace.test.tsx
+++ b/src/renderer/src/KnowledgeWorkspace.test.tsx
@@ -4,7 +4,8 @@ import {
   fireEvent,
   render,
   screen,
-  waitFor
+  waitFor,
+  within
 } from '@testing-library/react'
 import { afterEach, describe, expect, it, vi } from 'vitest'
 import {
@@ -143,6 +144,7 @@ function createProps(
     onCreateRelation: vi.fn(),
     onUpdateRelation: vi.fn(),
     onDeleteRelation: vi.fn(),
+    onRetryLoad: vi.fn(),
     ...overrides
   }
 }
@@ -283,10 +285,11 @@ describe('KnowledgeWorkspace', () => {
       'knowledge-workspace__sidebar'
     )
     expect(workspace.querySelector('aside')).not.toHaveAttribute('style')
-    expect(workspace.querySelector('main')).toHaveClass(
-      'knowledge-workspace__main'
-    )
-    expect(workspace.querySelector('main')).toHaveStyle({
+    const detailRegion = within(workspace).getByRole('region', {
+      name: '知识库详情'
+    })
+    expect(detailRegion).toHaveClass('knowledge-workspace__main')
+    expect(detailRegion).toHaveStyle({
       background: 'var(--surface-raised)'
     })
     expect(screen.getByText('全局')).toHaveClass('scope-badge')
@@ -308,6 +311,9 @@ describe('KnowledgeWorkspace', () => {
     expect(screen.getByLabelText('搜索文档').closest('label')).toHaveClass(
       'knowledge-documents__search'
     )
+    expect(screen.getByLabelText('搜索文档')).not.toHaveStyle({
+      outline: 'none'
+    })
     expect(screen.getByText('本地文件 · 架构说明.md')).toBeInTheDocument()
     expect(screen.queryByText('D:\\Private\\架构说明.md')).not
       .toBeInTheDocument()
@@ -609,6 +615,44 @@ describe('KnowledgeWorkspace', () => {
     ).toBeDisabled()
   })
 
+  it('shows a retryable load error instead of the first-library empty state', () => {
+    const onRetryLoad = vi.fn()
+    render(
+      <KnowledgeWorkspace
+        {...createProps({
+          libraries: [],
+          loadError: '数据库暂时不可用',
+          onRetryLoad,
+          selectedLibraryId: undefined
+        })}
+      />
+    )
+
+    expect(screen.getByText('知识库加载失败')).toBeInTheDocument()
+    expect(screen.getByText('数据库暂时不可用')).toBeInTheDocument()
+    expect(
+      screen.queryByText('建立第一个知识库')
+    ).not.toBeInTheDocument()
+    fireEvent.click(screen.getByRole('button', { name: '重试' }))
+    expect(onRetryLoad).toHaveBeenCalledOnce()
+  })
+
+  it('keeps existing data and selection visible when refresh fails', () => {
+    render(
+      <KnowledgeWorkspace
+        {...createProps({ loadError: '刷新连接失败' })}
+      />
+    )
+
+    expect(screen.getByText('知识库刷新失败')).toBeInTheDocument()
+    expect(screen.getByRole('heading', { name: library.name }))
+      .toBeInTheDocument()
+    expect(screen.getByText('架构说明.md')).toBeInTheDocument()
+    expect(
+      screen.getByRole('button', { name: /^产品知识 1 个文档/u })
+    ).toHaveAttribute('aria-current', 'page')
+  })
+
   it('confirms that deleting a managed library removes managed copies', async () => {
     const onDeleteLibrary = vi.fn()
     render(
diff --git a/src/renderer/src/KnowledgeWorkspace.tsx b/src/renderer/src/KnowledgeWorkspace.tsx
index 0a2777a..73625a1 100644
--- a/src/renderer/src/KnowledgeWorkspace.tsx
+++ b/src/renderer/src/KnowledgeWorkspace.tsx
@@ -159,6 +159,8 @@ export type KnowledgeWorkspaceProps = {
   graphRelations: readonly KnowledgeGraphRelation[]
   evidence: readonly KnowledgeEvidence[]
   loading?: boolean
+  loadError?: string
+  onRetryLoad: () => void | Promise<void>
   onSelectLibrary: (libraryId: string) => void
   onCreateLibrary: (
     input: CreateKnowledgeLibraryInput
@@ -274,7 +276,6 @@ const styles = {
     padding: 'var(--space-2) var(--space-3)',
     border: '1px solid var(--border-control)',
     borderRadius: 'var(--radius-control)',
-    outline: 'none',
     background: 'var(--surface-raised)',
     color: 'var(--text-primary)',
     font: 'inherit'
@@ -2115,6 +2116,8 @@ export function KnowledgeWorkspace({
   graphRelations,
   evidence,
   loading = false,
+  loadError,
+  onRetryLoad,
   onSelectLibrary,
   onCreateLibrary,
   onDeleteLibrary,
@@ -2323,10 +2326,33 @@ export function KnowledgeWorkspace({
           </nav>
         </aside>
 
-      <main
+      <section
+        aria-label="知识库详情"
         className="knowledge-workspace__main"
         style={{ minWidth: 0, background: 'var(--surface-raised)' }}
       >
+        {loadError && libraries.length > 0 && (
+          <div
+            role="alert"
+            style={{
+              ...styles.surface,
+              margin: 'var(--space-4)',
+              padding: 'var(--space-3)',
+              color: 'var(--danger)'
+            }}
+          >
+            <strong>知识库刷新失败</strong>
+            <p style={{ margin: 'var(--space-2) 0' }}>{loadError}</p>
+            <button
+              className="secondary-button"
+              onClick={() => void onRetryLoad()}
+              type="button"
+            >
+              <RefreshCw aria-hidden="true" size={14} />
+              重试
+            </button>
+          </div>
+        )}
         {selectedLibrary && !creating && !loading && (
           <button
             className="knowledge-workspace__mobile-back secondary-button"
@@ -2337,13 +2363,31 @@ export function KnowledgeWorkspace({
             返回知识库列表
           </button>
         )}
-        {loading ? (
+        {loading && libraries.length === 0 ? (
           <EmptyState
             description="正在读取知识库、来源和索引状态。"
             icon={<LoaderCircle size={28} />}
             level="page"
             title="正在加载知识库"
           />
+        ) : loadError && libraries.length === 0 ? (
+          <EmptyState
+            action={
+              <button
+                className="secondary-button"
+                onClick={() => void onRetryLoad()}
+                style={styles.button}
+                type="button"
+              >
+                <RefreshCw aria-hidden="true" size={14} />
+                重试
+              </button>
+            }
+            description={loadError}
+            icon={<AlertCircle size={28} />}
+            level="page"
+            title="知识库加载失败"
+          />
         ) : creating ? (
           <CreateLibraryWizard
             onCancel={() => setCreating(false)}
@@ -2502,7 +2546,7 @@ export function KnowledgeWorkspace({
             </div>
           </>
         )}
-      </main>
+      </section>
       {deletingLibrary && (
         <DeleteLibraryDialog
           library={deletingLibrary}
diff --git a/src/renderer/src/MagicNotesWorkspace.test.tsx b/src/renderer/src/MagicNotesWorkspace.test.tsx
index 037f77d..0ccb680 100644
--- a/src/renderer/src/MagicNotesWorkspace.test.tsx
+++ b/src/renderer/src/MagicNotesWorkspace.test.tsx
@@ -123,6 +123,7 @@ const summaryFromDetail = (
 const list = vi.fn<() => Promise<MagicNotesSnapshot>>()
 const get = vi.fn<(noteId: string) => Promise<MagicNoteDetail>>()
 const listTodos = vi.fn<() => Promise<MagicTodosSnapshot>>()
+const remove = vi.fn<DesktopApi['magicNotes']['remove']>()
 const createTodo = vi.fn<DesktopApi['magicNotes']['createTodo']>()
 const updateTodo = vi.fn<DesktopApi['magicNotes']['updateTodo']>()
 const removeTodo = vi.fn<DesktopApi['magicNotes']['removeTodo']>()
@@ -133,6 +134,7 @@ beforeEach(() => {
   list.mockResolvedValue({ notes: [detail] })
   get.mockResolvedValue(detail)
   listTodos.mockResolvedValue({ todos: [noteTodo, manualTodo] })
+  remove.mockResolvedValue()
   createTodo.mockResolvedValue({
     ...manualTodo,
     id: '00000000-0000-4000-8000-000000000606',
@@ -166,6 +168,7 @@ beforeEach(() => {
         list,
         get,
         listTodos,
+        remove,
         createTodo,
         updateTodo,
         removeTodo,
@@ -181,6 +184,68 @@ afterEach(() => {
 })
 
 describe('MagicNotesWorkspace', () => {
+  it('shows a retryable EmptyState when the initial load fails', async () => {
+    get.mockRejectedValueOnce(new Error('详情暂时不可用'))
+
+    render(
+      <MagicNotesWorkspace
+        onNotify={onNotify}
+        projectId={detail.projectId}
+        projectName="默认项目"
+      />
+    )
+
+    expect(
+      await screen.findByText('魔法笔记加载失败')
+    ).toBeInTheDocument()
+    expect(screen.getByText(/详情暂时不可用/)).toBeInTheDocument()
+    expect(screen.queryByText('还没有笔记')).not.toBeInTheDocument()
+    expect(screen.queryByText('还没有待办')).not.toBeInTheDocument()
+    expect(screen.queryByText('还没有选择笔记')).not.toBeInTheDocument()
+    expect(onNotify).not.toHaveBeenCalled()
+
+    fireEvent.click(screen.getByRole('button', { name: '重试' }))
+
+    expect(await screen.findByText('记录正文')).toBeInTheDocument()
+    expect(screen.queryByText('魔法笔记加载失败')).not.toBeInTheDocument()
+  })
+
+  it('keeps successful data and selection when a refresh fails', async () => {
+    render(
+      <MagicNotesWorkspace
+        onNotify={onNotify}
+        projectId={detail.projectId}
+        projectName="默认项目"
+      />
+    )
+
+    await screen.findByText('记录正文')
+    list.mockRejectedValueOnce(new Error('刷新暂时不可用'))
+    fireEvent.click(screen.getByRole('button', { name: '删除笔记' }))
+    fireEvent.click(
+      screen.getAllByRole('button', { name: '删除笔记' })[1]!
+    )
+
+    expect(
+      await screen.findByText(/刷新失败，已保留当前内容：刷新暂时不可用/)
+    ).toBeInTheDocument()
+    expect(screen.getByLabelText('笔记标题')).toHaveValue(detail.title)
+    expect(
+      screen.getByRole('button', { name: /发布笔记/ })
+    ).toHaveAttribute('aria-pressed', 'true')
+    fireEvent.click(screen.getByRole('tab', { name: '待办' }))
+    expect(screen.getByText('准备演示')).toBeInTheDocument()
+    expect(
+      screen.getByRole('button', { name: /核对发布材料/ })
+    ).toHaveAttribute('aria-pressed', 'true')
+    expect(onNotify).not.toHaveBeenCalledWith(
+      expect.objectContaining({
+        tone: 'error',
+        message: '刷新暂时不可用'
+      })
+    )
+  })
+
   it('aggregates note and manual todos without AI-created todo actions', async () => {
     render(
       <MagicNotesWorkspace
@@ -276,6 +341,53 @@ describe('MagicNotesWorkspace', () => {
     )
   })
 
+  it('does not override a note selected while retrying a refresh', async () => {
+    const second = alternateDetail(secondNoteId, '第二篇笔记')
+    list.mockResolvedValue({
+      notes: [summaryFromDetail(detail), summaryFromDetail(second)]
+    })
+
+    render(
+      <MagicNotesWorkspace
+        onNotify={onNotify}
+        projectId={detail.projectId}
+        projectName="默认项目"
+      />
+    )
+
+    await screen.findByText('记录正文')
+    list.mockRejectedValueOnce(new Error('刷新暂时不可用'))
+    fireEvent.click(screen.getByRole('button', { name: '删除笔记' }))
+    fireEvent.click(
+      screen.getAllByRole('button', { name: '删除笔记' })[1]!
+    )
+    const retry = await screen.findByRole('button', { name: '重试' })
+
+    let resolveRefreshDetail:
+      | ((value: MagicNoteDetail) => void)
+      | undefined
+    const delayedRefreshDetail = new Promise<MagicNoteDetail>(
+      (resolve) => {
+        resolveRefreshDetail = resolve
+      }
+    )
+    get.mockImplementation((requestedId) =>
+      requestedId === second.id
+        ? Promise.resolve(second)
+        : delayedRefreshDetail
+    )
+
+    fireEvent.click(retry)
+    await waitFor(() => expect(get).toHaveBeenCalledTimes(2))
+    fireEvent.click(screen.getByText(second.title).closest('button')!)
+    expect(await screen.findByDisplayValue(second.title)).toBeInTheDocument()
+
+    resolveRefreshDetail?.(detail)
+    await waitFor(() =>
+      expect(screen.getByLabelText('笔记标题')).toHaveValue(second.title)
+    )
+  })
+
   it('creates a manual todo with a dedicated title and details form', async () => {
     render(
       <MagicNotesWorkspace
@@ -289,7 +401,7 @@ describe('MagicNotesWorkspace', () => {
     fireEvent.click(screen.getByRole('tab', { name: '待办' }))
     fireEvent.click(screen.getByRole('button', { name: '新建待办' }))
     expect(createTodo).not.toHaveBeenCalled()
-    fireEvent.click(screen.getByRole('button', { name: '创建' }))
+    fireEvent.click(screen.getByRole('button', { name: '创建待办' }))
     expect(screen.getByRole('alert')).toHaveTextContent('请输入待办标题')
     expect(onNotify).not.toHaveBeenCalled()
 
@@ -300,7 +412,7 @@ describe('MagicNotesWorkspace', () => {
     fireEvent.change(screen.getByLabelText('说明'), {
       target: { value: '新增说明' }
     })
-    fireEvent.click(screen.getByRole('button', { name: '创建' }))
+    fireEvent.click(screen.getByRole('button', { name: '创建待办' }))
 
     await waitFor(() =>
       expect(createTodo).toHaveBeenCalledWith({
@@ -335,6 +447,41 @@ describe('MagicNotesWorkspace', () => {
     ).toBeInTheDocument()
   })
 
+  it('clears note searches and todo status filters with no results', async () => {
+    listTodos.mockResolvedValue({
+      todos: [
+        { ...noteTodo, completed: true },
+        { ...manualTodo, completed: true }
+      ]
+    })
+    render(
+      <MagicNotesWorkspace
+        onNotify={onNotify}
+        projectId={detail.projectId}
+        projectName="默认项目"
+      />
+    )
+
+    await screen.findByText('记录正文')
+    fireEvent.change(screen.getByRole('searchbox', { name: '搜索当前范围的笔记' }), {
+      target: { value: '不存在的笔记' }
+    })
+    expect(screen.getByText('没有符合条件的笔记')).toBeInTheDocument()
+    fireEvent.click(screen.getByRole('button', { name: '清除筛选' }))
+    expect(screen.getByRole('searchbox', {
+      name: '搜索当前范围的笔记'
+    })).toHaveValue('')
+    expect(screen.getByText('发布笔记')).toBeInTheDocument()
+
+    fireEvent.click(screen.getByRole('tab', { name: '待办' }))
+    expect(screen.getByText('没有符合条件的待办')).toBeInTheDocument()
+    fireEvent.click(screen.getByRole('button', { name: '清除筛选' }))
+    expect(
+      screen.getByRole('button', { name: '全部' })
+    ).toHaveAttribute('aria-pressed', 'true')
+    expect(screen.getAllByText('核对发布材料')).not.toHaveLength(0)
+  })
+
   it('clears delete confirmation before selecting the next todo', async () => {
     render(
       <MagicNotesWorkspace
diff --git a/src/renderer/src/MagicNotesWorkspace.tsx b/src/renderer/src/MagicNotesWorkspace.tsx
index f52605e..92aef1d 100644
--- a/src/renderer/src/MagicNotesWorkspace.tsx
+++ b/src/renderer/src/MagicNotesWorkspace.tsx
@@ -49,6 +49,7 @@ export type MagicNotesWorkspaceProps = {
 
 type LibraryView = 'notes' | 'todos'
 type TodoFilter = 'active' | 'completed' | 'all'
+type LoadStatus = 'loading' | 'ready' | 'error'
 type ValidationTarget =
   | 'create-note'
   | 'create-todo'
@@ -150,7 +151,13 @@ export function MagicNotesWorkspace({
   const [selectedNoteId, setSelectedNoteId] = useState('')
   const [selectedTodoId, setSelectedTodoId] = useState('')
   const [detail, setDetail] = useState<MagicNoteDetail>()
-  const [loading, setLoading] = useState(true)
+  const [loadStatus, setLoadStatus] = useState<LoadStatus>('loading')
+  const [loadError, setLoadError] = useState('')
+  const [refreshError, setRefreshError] = useState('')
+  const [detailLoadError, setDetailLoadError] = useState<{
+    message: string
+    noteId: string
+  }>()
   const [busy, setBusy] = useState('')
   const [search, setSearch] = useState('')
   const [creating, setCreating] = useState(false)
@@ -172,7 +179,9 @@ export function MagicNotesWorkspace({
     message: string
   }>()
   const detailRequestRef = useRef(0)
+  const requestedNoteIdRef = useRef('')
   const refreshRequestRef = useRef(0)
+  const hasLoadedRef = useRef(false)
   const busyRef = useRef('')
   const composerContentRef = useRef<MagicNoteRichContent | undefined>(
     undefined
@@ -258,28 +267,40 @@ export function MagicNotesWorkspace({
   const loadDetail = useCallback(
     async (noteId: string): Promise<void> => {
       const requestId = ++detailRequestRef.current
+      requestedNoteIdRef.current = noteId
+      setDetailLoadError(undefined)
       try {
         const nextDetail = await window.goodbuddy.magicNotes.get(noteId)
         if (detailRequestRef.current === requestId) {
+          setSelectedNoteId(noteId)
           applyDetail(nextDetail)
         }
       } catch (loadError) {
         if (detailRequestRef.current === requestId) {
-          notifyError(loadError)
+          setDetailLoadError({
+            message: errorMessage(loadError),
+            noteId
+          })
         }
       }
     },
-    [applyDetail, notifyError]
+    [applyDetail]
   )
 
   const refreshNotes = useCallback(
     async (preferredId?: string): Promise<void> => {
       const requestId = ++refreshRequestRef.current
+      const detailRequestAtStart = detailRequestRef.current
       await Promise.resolve()
       if (refreshRequestRef.current !== requestId) {
         return
       }
-      setLoading(true)
+      const isInitialLoad = !hasLoadedRef.current
+      if (isInitialLoad) {
+        setLoadStatus('loading')
+        setLoadError('')
+      }
+      setRefreshError('')
       try {
         const [snapshot, todoSnapshot] = await Promise.all([
           window.goodbuddy.magicNotes.list(projectId),
@@ -295,23 +316,37 @@ export function MagicNotesWorkspace({
         if (refreshRequestRef.current !== requestId) {
           return
         }
+        const requestedNoteId = requestedNoteIdRef.current
+        const preserveNewerSelection =
+          detailRequestRef.current !== detailRequestAtStart &&
+          snapshot.notes.some((note) => note.id === requestedNoteId)
         setNotes(snapshot.notes)
         setTodos(todoSnapshot.todos)
-        setSelectedNoteId(nextId)
         setSelectedTodoId(todoSnapshot.todos[0]?.id ?? '')
+        hasLoadedRef.current = true
+        setLoadStatus('ready')
+        if (preserveNewerSelection) {
+          return
+        }
+        detailRequestRef.current += 1
+        requestedNoteIdRef.current = nextId
+        setSelectedNoteId(nextId)
         setDetail(nextDetail)
         setTitleDraft(nextDetail?.title ?? '')
+        setDetailLoadError(undefined)
       } catch (loadError) {
         if (refreshRequestRef.current === requestId) {
-          notifyError(loadError)
-        }
-      } finally {
-        if (refreshRequestRef.current === requestId) {
-          setLoading(false)
+          const message = errorMessage(loadError)
+          if (hasLoadedRef.current) {
+            setRefreshError(message)
+          } else {
+            setLoadError(message)
+            setLoadStatus('error')
+          }
         }
       }
     },
-    [notifyError, projectId]
+    [projectId]
   )
 
   useEffect(() => {
@@ -321,6 +356,7 @@ export function MagicNotesWorkspace({
     return () => {
       window.clearTimeout(timeout)
       refreshRequestRef.current += 1
+      detailRequestRef.current += 1
     }
   }, [refreshNotes])
 
@@ -391,6 +427,7 @@ export function MagicNotesWorkspace({
         title
       })
       applyDetail(created)
+      requestedNoteIdRef.current = created.id
       setSelectedNoteId(created.id)
       setNewTitle('')
       setCreating(false)
@@ -649,7 +686,7 @@ export function MagicNotesWorkspace({
                 setCreating(true)
               }}
             >
-              <Plus size={15} />
+              <Plus aria-hidden="true" size={15} />
               {libraryView === 'notes' ? '新建笔记' : '新建待办'}
             </button>
           </>
@@ -666,6 +703,36 @@ export function MagicNotesWorkspace({
         title="魔法笔记"
       />
 
+      {loadStatus === 'error' ? (
+        <EmptyState
+          action={
+            <button
+              className="secondary-button"
+              onClick={() => void refreshNotes()}
+              type="button"
+            >
+              重试
+            </button>
+          }
+          description={`无法加载魔法笔记：${loadError}`}
+          icon={<CircleAlert size={24} />}
+          level="page"
+          title="魔法笔记加载失败"
+        />
+      ) : (
+        <>
+          {refreshError && (
+            <div className="magic-note-delete-confirmation" role="alert">
+              <span>刷新失败，已保留当前内容：{refreshError}</span>
+              <button
+                className="secondary-button"
+                onClick={() => void refreshNotes(selectedNoteId)}
+                type="button"
+              >
+                重试
+              </button>
+            </div>
+          )}
       <div
         aria-busy={Boolean(busy)}
         className={`magic-notes-layout${
@@ -760,18 +827,31 @@ export function MagicNotesWorkspace({
                   disabled={busy === 'create-note'}
                   type="submit"
                 >
-                  创建
+                  创建笔记
                 </button>
               </div>
             </form>
           )}
           <div className="magic-notes-list">
-            {loading ? (
+            {loadStatus === 'loading' ? (
               <p className="magic-notes-muted">正在加载笔记…</p>
             ) : visibleNotes.length === 0 ? (
-              <p className="magic-notes-muted">
-                {search ? '没有符合条件的笔记' : '还没有笔记'}
-              </p>
+              <>
+                <p className="magic-notes-muted">
+                  {search.trim()
+                    ? '没有符合条件的笔记'
+                    : '还没有笔记'}
+                </p>
+                {search.trim() && (
+                  <button
+                    className="secondary-button"
+                    onClick={() => setSearch('')}
+                    type="button"
+                  >
+                    清除筛选
+                  </button>
+                )}
+              </>
             ) : (
               visibleNotes.map((note) => (
                 <button
@@ -785,7 +865,6 @@ export function MagicNotesWorkspace({
                   type="button"
                   onClick={() => {
                     setValidation(undefined)
-                    setSelectedNoteId(note.id)
                     setDeletingNote(false)
                     setEditingEntry(undefined)
                     editingContentRef.current = undefined
@@ -895,22 +974,38 @@ export function MagicNotesWorkspace({
                       disabled={busy === 'create-todo'}
                       type="submit"
                     >
-                      创建
+                      创建待办
                     </button>
                   </div>
                 </form>
               )}
               <div className="magic-notes-list">
-                {loading ? (
+                {loadStatus === 'loading' ? (
                   <p className="magic-notes-muted">正在加载待办…</p>
                 ) : visibleTodos.length === 0 ? (
-                  <p className="magic-notes-muted">
-                    {todos.length === 0
-                      ? '还没有待办'
-                      : search || todoFilter !== 'all'
-                      ? '没有符合条件的待办'
-                      : '还没有待办'}
-                  </p>
+                  <>
+                    <p className="magic-notes-muted">
+                      {todos.length === 0
+                        ? '还没有待办'
+                        : search.trim() || todoFilter !== 'all'
+                          ? '没有符合条件的待办'
+                          : '还没有待办'}
+                    </p>
+                    {todos.length > 0 &&
+                      (Boolean(search.trim()) ||
+                        todoFilter !== 'all') && (
+                        <button
+                          className="secondary-button"
+                          onClick={() => {
+                            setSearch('')
+                            setTodoFilter('all')
+                          }}
+                          type="button"
+                        >
+                          清除筛选
+                        </button>
+                      )}
+                  </>
                 ) : (
                   visibleTodos.map((todo) => (
                     <button
@@ -955,7 +1050,7 @@ export function MagicNotesWorkspace({
           )}
         </aside>
 
-        <main
+        <section
           aria-label={libraryView === 'notes' ? '笔记记录' : '待办详情'}
           className="magic-notes-stream-pane"
         >
@@ -964,10 +1059,27 @@ export function MagicNotesWorkspace({
             <EmptyState
               description="从左侧选择笔记，或新建一篇笔记开始记录。"
               icon={<FileText size={24} />}
-              title={loading ? '正在加载' : '还没有选择笔记'}
+              title={
+                loadStatus === 'loading' ? '正在加载' : '还没有选择笔记'
+              }
             />
           ) : (
             <>
+              {detailLoadError && (
+                <div className="magic-note-delete-confirmation" role="alert">
+                  <span>
+                    笔记加载失败，已保留当前内容：
+                    {detailLoadError.message}
+                  </span>
+                  <button
+                    className="secondary-button"
+                    onClick={() => void loadDetail(detailLoadError.noteId)}
+                    type="button"
+                  >
+                    重试
+                  </button>
+                </div>
+              )}
               <header className="magic-note-detail-header">
                 <input
                   aria-describedby={
@@ -1278,7 +1390,9 @@ export function MagicNotesWorkspace({
             <EmptyState
               description="从左侧选择待办，或新建一个手动待办。"
               icon={<ListTodo size={24} />}
-              title={loading ? '正在加载' : '还没有选择待办'}
+              title={
+                loadStatus === 'loading' ? '正在加载' : '还没有选择待办'
+              }
             />
           ) : (
             <section className="magic-todo-detail">
@@ -1451,7 +1565,6 @@ export function MagicNotesWorkspace({
                         className="secondary-button"
                         onClick={() => {
                           setLibraryView('notes')
-                          setSelectedNoteId(selectedTodo.noteId!)
                           void loadDetail(selectedTodo.noteId!).then(() => {
                             requestAnimationFrame(() =>
                               document
@@ -1472,7 +1585,7 @@ export function MagicNotesWorkspace({
               )}
             </section>
           )}
-        </main>
+        </section>
 
         <aside
           aria-label="AI 评论"
@@ -1533,6 +1646,8 @@ export function MagicNotesWorkspace({
           )}
         </aside>
       </div>
+        </>
+      )}
     </div>
   )
 }
diff --git a/src/renderer/src/PlatformFeaturesSettingsSection.tsx b/src/renderer/src/PlatformFeaturesSettingsSection.tsx
new file mode 100644
index 0000000..7d31e32
--- /dev/null
+++ b/src/renderer/src/PlatformFeaturesSettingsSection.tsx
@@ -0,0 +1,106 @@
+import { Sparkles } from 'lucide-react'
+import { useEffect, useState } from 'react'
+import type { ApplicationSettings } from '../../shared/application-settings-contracts'
+
+type PlatformFeaturesSettingsSectionProps = {
+  onMagicNotesEnabledChange: (enabled: boolean) => void
+}
+
+export function PlatformFeaturesSettingsSection({
+  onMagicNotesEnabledChange
+}: PlatformFeaturesSettingsSectionProps): React.JSX.Element {
+  const [settings, setSettings] = useState<ApplicationSettings>()
+  const [saving, setSaving] = useState(false)
+  const [error, setError] = useState<string | undefined>(() =>
+    window.goodbuddy.updates
+      ? undefined
+      : '当前版本未提供应用设置服务'
+  )
+
+  useEffect(() => {
+    const updates = window.goodbuddy.updates
+    let active = true
+    if (!updates) {
+      return () => {
+        active = false
+      }
+    }
+    void updates
+      .getSettings()
+      .then((nextSettings) => {
+        if (active) {
+          setSettings(nextSettings)
+        }
+      })
+      .catch(() => {
+        if (active) {
+          setError('读取平台功能设置失败')
+        }
+      })
+    return () => {
+      active = false
+    }
+  }, [])
+
+  const changeMagicNotes = async (enabled: boolean): Promise<void> => {
+    const updates = window.goodbuddy.updates
+    if (!updates || !settings) {
+      return
+    }
+    setSaving(true)
+    setError(undefined)
+    try {
+      const nextSettings = await updates.updateSettings({
+        magicNotesEnabled: enabled
+      })
+      setSettings(nextSettings)
+      onMagicNotesEnabledChange(nextSettings.magicNotesEnabled)
+    } catch {
+      setError('保存魔法笔记设置失败，请重试')
+    } finally {
+      setSaving(false)
+    }
+  }
+
+  return (
+    <section
+      aria-labelledby="platform-features-heading"
+      className="settings-section"
+    >
+      <div className="settings-section__title">
+        <Sparkles aria-hidden="true" size={17} />
+        <div>
+          <strong id="platform-features-heading">平台功能</strong>
+          <small>控制 GoodBuddy 工作区中显示的功能入口</small>
+        </div>
+      </div>
+      <article className="capability-card">
+        <div className="capability-card__header">
+          <div>
+            <strong>魔法笔记</strong>
+            <small>
+              默认关闭；开启后可记录笔记与待办，并使用 AI 分析内容
+            </small>
+          </div>
+        </div>
+        <label className="toggle-row">
+          <input
+            checked={settings?.magicNotesEnabled ?? false}
+            disabled={!settings || saving}
+            onChange={(event) =>
+              void changeMagicNotes(event.target.checked)
+            }
+            role="switch"
+            type="checkbox"
+          />
+          <span>显示魔法笔记入口</span>
+        </label>
+      </article>
+      {error && (
+        <p className="settings-warning" role="alert">
+          {error}
+        </p>
+      )}
+    </section>
+  )
+}
diff --git a/src/renderer/src/SettingsPanel.test.tsx b/src/renderer/src/SettingsPanel.test.tsx
index 520dfa3..e0bc1b0 100644
--- a/src/renderer/src/SettingsPanel.test.tsx
+++ b/src/renderer/src/SettingsPanel.test.tsx
@@ -325,10 +325,30 @@ const onEmbeddingStatus = vi.fn(
     }
   }
 )
+let applicationSettings = {
+  checkUpdatesOnStartup: true,
+  magicNotesEnabled: false
+}
+const getApplicationSettings = vi.fn(async () => ({
+  ...applicationSettings
+}))
+const updateApplicationSettings = vi.fn<
+  NonNullable<DesktopApi['updates']>['updateSettings']
+>(async (input) => {
+  applicationSettings = {
+    ...applicationSettings,
+    ...input
+  }
+  return { ...applicationSettings }
+})
 
 describe('SettingsPanel runtime files', () => {
   beforeEach(() => {
     vi.clearAllMocks()
+    applicationSettings = {
+      checkUpdatesOnStartup: true,
+      magicNotesEnabled: false
+    }
     embeddingStatusListeners.splice(0)
     Object.defineProperty(window, 'goodbuddy', {
       configurable: true,
@@ -377,6 +397,13 @@ describe('SettingsPanel runtime files', () => {
           rebuild: rebuildEmbeddingIndex,
           cancel: cancelEmbeddingIndex,
           onStatus: onEmbeddingStatus
+        },
+        updates: {
+          getSettings: getApplicationSettings,
+          updateSettings: updateApplicationSettings,
+          check: vi.fn(),
+          openReleasePage: vi.fn(),
+          onResult: vi.fn(() => () => {})
         }
       } as unknown as DesktopApi
     })
@@ -408,6 +435,35 @@ describe('SettingsPanel runtime files', () => {
     expect(onAppearanceThemeChange).toHaveBeenCalledWith('dark')
   })
 
+  it('toggles the Magic Notes platform entry setting', async () => {
+    const onMagicNotesEnabledChange = vi.fn()
+    render(
+      <SettingsPanel
+        {...heartbeatSettingsProps}
+        onMagicNotesEnabledChange={onMagicNotesEnabledChange}
+        open
+        onClearLocalData={vi.fn(async () => {})}
+        onClose={vi.fn()}
+        onSaved={vi.fn()}
+      />
+    )
+
+    fireEvent.click(screen.getByRole('tab', { name: '平台功能' }))
+    const toggle = await screen.findByRole('switch', {
+      name: '显示魔法笔记入口'
+    })
+    expect(toggle).not.toBeChecked()
+    expect(screen.getByText(/默认关闭/)).toBeInTheDocument()
+    fireEvent.click(toggle)
+
+    await waitFor(() =>
+      expect(updateApplicationSettings).toHaveBeenCalledWith({
+        magicNotesEnabled: true
+      })
+    )
+    expect(onMagicNotesEnabledChange).toHaveBeenCalledWith(true)
+  })
+
   it('keeps page navigation beside an independently scrollable panel', () => {
     render(
       <SettingsPanel
@@ -429,6 +485,63 @@ describe('SettingsPanel runtime files', () => {
     expect(content).toHaveClass('settings-panel__content')
   })
 
+  it('uses one first-level heading for the settings page', () => {
+    render(
+      <SettingsPanel
+        {...heartbeatSettingsProps}
+        open
+        onClearLocalData={vi.fn(async () => {})}
+        onClose={vi.fn()}
+        onSaved={vi.fn()}
+        presentation="page"
+      />
+    )
+
+    expect(
+      screen.getAllByRole('heading', { level: 1 })
+    ).toHaveLength(1)
+    expect(
+      screen.getByRole('heading', { level: 1, name: '设置中心' })
+    ).toBeInTheDocument()
+  })
+
+  it('keeps local progress but does not duplicate clear-data success', async () => {
+    let finishClear: (() => void) | undefined
+    const onClearLocalData = vi.fn(
+      () =>
+        new Promise<void>((resolve) => {
+          finishClear = resolve
+        })
+    )
+    render(
+      <SettingsPanel
+        {...heartbeatSettingsProps}
+        open
+        onClearLocalData={onClearLocalData}
+        onClose={vi.fn()}
+        onSaved={vi.fn()}
+      />
+    )
+
+    fireEvent.click(screen.getByRole('tab', { name: '安全与数据' }))
+    fireEvent.click(
+      screen.getByRole('button', { name: '清除本地数据' })
+    )
+    fireEvent.click(
+      screen.getByRole('button', { name: '清除本地数据' })
+    )
+
+    expect(
+      screen.getByRole('button', { name: '正在清除…' })
+    ).toBeDisabled()
+    await act(async () => finishClear?.())
+    await waitFor(() =>
+      expect(
+        screen.queryByText('本地数据已清除')
+      ).not.toBeInTheDocument()
+    )
+  })
+
   it('supports keyboard navigation between settings tabs', () => {
     render(
       <SettingsPanel
diff --git a/src/renderer/src/SettingsPanel.tsx b/src/renderer/src/SettingsPanel.tsx
index d4fe9b4..9e5cac0 100644
--- a/src/renderer/src/SettingsPanel.tsx
+++ b/src/renderer/src/SettingsPanel.tsx
@@ -34,9 +34,10 @@ import { SkillsSettingsSection } from './SkillsSettingsSection'
 import { HeartbeatSettings } from './HeartbeatSettings'
 import { ChannelSettingsSection } from './ChannelSettingsSection'
 import { UpdateSettingsSection } from './UpdateSettingsSection'
+import { PlatformFeaturesSettingsSection } from './PlatformFeaturesSettingsSection'
 import { SpeechModelSettingsSection } from './SpeechModelSettingsSection'
 import { EmbeddingSettingsSection } from './EmbeddingSettingsSection'
-import { SegmentedControl } from './WorkspacePrimitives'
+import { PageHeader, SegmentedControl } from './WorkspacePrimitives'
 import type { AppearanceTheme } from './theme'
 import type { AppNotificationInput } from './notifications'
 import type {
@@ -46,6 +47,7 @@ import type {
 
 type SettingsTab =
   | 'appearance'
+  | 'platform-features'
   | 'model'
   | 'runtime'
   | 'security'
@@ -64,6 +66,7 @@ type ModelProfileDraft = RuntimeSettings['modelProfiles'][number] & {
 
 const settingsTabs: readonly SettingsTab[] = [
   'appearance',
+  'platform-features',
   'model',
   'runtime',
   'security',
@@ -93,6 +96,7 @@ type SettingsPanelProps = {
   onRunHeartbeat: (heartbeatId: string) => Promise<void>
   appearanceTheme?: AppearanceTheme
   onAppearanceThemeChange?: (theme: AppearanceTheme) => void
+  onMagicNotesEnabledChange?: (enabled: boolean) => void
 }
 
 const credentialLabels: Record<
@@ -255,7 +259,8 @@ export function SettingsPanel({
   onRunHeartbeat,
   onExpertsChanged = () => {},
   appearanceTheme = 'system',
-  onAppearanceThemeChange = () => {}
+  onAppearanceThemeChange = () => {},
+  onMagicNotesEnabledChange = () => {}
 }: SettingsPanelProps): React.JSX.Element | null {
   const [settings, setSettings] = useState<RuntimeSettings>()
   const [provider, setProvider] =
@@ -328,6 +333,7 @@ export function SettingsPanel({
   const [saved, setSaved] = useState(false)
   const [connectionResult, setConnectionResult] = useState<string>()
   const [confirmingClear, setConfirmingClear] = useState(false)
+  const [clearingLocalData, setClearingLocalData] = useState(false)
   const [detection, setDetection] = useState<AgentRuntimeDetection>()
   const [detecting, setDetecting] = useState(false)
   const [activeTab, setActiveTab] = useState<SettingsTab>('runtime')
@@ -382,6 +388,7 @@ export function SettingsPanel({
         setSaved(false)
         setConnectionResult(undefined)
         setConfirmingClear(false)
+        setClearingLocalData(false)
         setModelType('llm')
         setAgentRuntimeType('opencode')
         setSettings(value)
@@ -951,23 +958,26 @@ export function SettingsPanel({
         className="settings-panel"
         role={presentation === 'modal' ? 'dialog' : 'region'}
       >
-        <header className="settings-panel__header">
+        <div className="settings-panel__header">
           <div>
-            <p className="eyebrow">SETTINGS</p>
-            <h2 id="settings-title">设置中心</h2>
-            <p className="settings-panel__description">
-              管理模型连接、Agent Runtime、自动化、扩展能力和本地数据。
-            </p>
+            <PageHeader
+              actions={
+                <button
+                  aria-label="关闭设置"
+                  className="icon-button"
+                  onClick={close}
+                  type="button"
+                >
+                  <X aria-hidden="true" size={19} />
+                </button>
+              }
+              description="管理模型连接、Agent Runtime、自动化、扩展能力和本地数据。"
+              eyebrow="SETTINGS"
+              headingId="settings-title"
+              title="设置中心"
+            />
           </div>
-          <button
-            aria-label="关闭设置"
-            className="icon-button"
-            onClick={close}
-            type="button"
-          >
-            <X size={19} />
-          </button>
-        </header>
+        </div>
 
         <div className="settings-panel__body">
           <nav
@@ -992,6 +1002,22 @@ export function SettingsPanel({
               <strong>外观</strong>
               <small>亮色、暗色与系统主题</small>
             </button>
+            <button
+              aria-controls="settings-panel-platform-features"
+              aria-label="平台功能"
+              aria-selected={activeTab === 'platform-features'}
+              id="settings-tab-platform-features"
+              onClick={() => setActiveTab('platform-features')}
+              onKeyDown={(event) =>
+                handleTabKeyDown(event, 'platform-features')
+              }
+              role="tab"
+              tabIndex={activeTab === 'platform-features' ? 0 : -1}
+              type="button"
+            >
+              <strong>平台功能</strong>
+              <small>功能入口与工作区能力</small>
+            </button>
             <button
               aria-controls="settings-panel-model"
               aria-label="模型连接"
@@ -1189,6 +1215,11 @@ export function SettingsPanel({
               </div>
             </div>
           )}
+          {activeTab === 'platform-features' && (
+            <PlatformFeaturesSettingsSection
+              onMagicNotesEnabledChange={onMagicNotesEnabledChange}
+            />
+          )}
           {activeTab === 'runtime' && (
             <>
               {settings?.warning && (
@@ -2165,6 +2196,7 @@ export function SettingsPanel({
               <div className="danger-actions">
                 <button
                   className="secondary-button"
+                  disabled={clearingLocalData}
                   onClick={() => setConfirmingClear(false)}
                   type="button"
                 >
@@ -2172,12 +2204,15 @@ export function SettingsPanel({
                 </button>
                 <button
                   className="danger-button"
+                  disabled={clearingLocalData}
                   onClick={() => {
+                    setClearingLocalData(true)
+                    setError(undefined)
+                    setSaved(false)
+                    setConnectionResult(undefined)
                     void onClearLocalData()
                       .then(() => {
                         setConfirmingClear(false)
-                        setConnectionResult('本地数据已清除')
-                        setSaved(true)
                       })
                       .catch((reason: unknown) => {
                         setError(
@@ -2187,10 +2222,13 @@ export function SettingsPanel({
                           )
                         )
                       })
+                      .finally(() => setClearingLocalData(false))
                   }}
                   type="button"
                 >
-                  确认清除
+                  {clearingLocalData
+                    ? '正在清除…'
+                    : '清除本地数据'}
                 </button>
               </div>
             ) : (
diff --git a/src/renderer/src/UpdateSettingsSection.test.tsx b/src/renderer/src/UpdateSettingsSection.test.tsx
index 86e65ba..37d4d40 100644
--- a/src/renderer/src/UpdateSettingsSection.test.tsx
+++ b/src/renderer/src/UpdateSettingsSection.test.tsx
@@ -18,7 +18,11 @@ describe('UpdateSettingsSection', () => {
   it('checks the official release manifest and updates the startup preference', async () => {
     const updateSettings = vi.fn<
       NonNullable<DesktopApi['updates']>['updateSettings']
-    >(async (input) => input)
+    >(async (input) => ({
+      checkUpdatesOnStartup:
+        input.checkUpdatesOnStartup ?? true,
+      magicNotesEnabled: input.magicNotesEnabled ?? true
+    }))
     const check = vi.fn<
       NonNullable<DesktopApi['updates']>['check']
     >(async () => ({
@@ -54,7 +58,8 @@ describe('UpdateSettingsSection', () => {
         },
         updates: {
           getSettings: vi.fn(async () => ({
-            checkUpdatesOnStartup: true
+            checkUpdatesOnStartup: true,
+            magicNotesEnabled: true
           })),
           updateSettings,
           check,
@@ -101,9 +106,13 @@ describe('UpdateSettingsSection', () => {
         },
         updates: {
           getSettings: vi.fn(async () => ({
-            checkUpdatesOnStartup: true
+            checkUpdatesOnStartup: true,
+            magicNotesEnabled: true
+          })),
+          updateSettings: vi.fn(async () => ({
+            checkUpdatesOnStartup: true,
+            magicNotesEnabled: true
           })),
-          updateSettings: vi.fn(async (input) => input),
           check: vi.fn(async () => {
             throw new Error(
               "Error invoking remote method 'application:update:check': TypeError: fetch failed"
diff --git a/src/renderer/src/WorkspacePrimitives.test.tsx b/src/renderer/src/WorkspacePrimitives.test.tsx
index ba3bd58..57f4751 100644
--- a/src/renderer/src/WorkspacePrimitives.test.tsx
+++ b/src/renderer/src/WorkspacePrimitives.test.tsx
@@ -98,6 +98,34 @@ describe('WorkspacePrimitives', () => {
     )
   })
 
+  it('keeps shared controls keyboard and pointer accessible at narrow widths', () => {
+    expect(stylesheet).toMatch(
+      /\.window-control\s*>\s*svg,\s*\.icon-button\s*>\s*svg\s*\{[^}]*pointer-events:\s*none;/u
+    )
+    expect(stylesheet).toMatch(
+      /button:focus-visible,\s*input:focus-visible,\s*select:focus-visible,\s*textarea:focus-visible\s*\{[^}]*outline:\s*2px solid var\(--accent\);/u
+    )
+    expect(stylesheet).toMatch(
+      /\.page-tabs\s*\{[^}]*overflow-x:\s*auto;[^}]*flex-wrap:\s*nowrap;/u
+    )
+    expect(stylesheet).not.toContain(
+      '.heartbeat-center > .page-tabs {\n    display: grid;'
+    )
+  })
+
+  it('uses the design-system page gutters at each window width', () => {
+    expect(stylesheet).toMatch(/--page-gutter:\s*32px;/u)
+    expect(stylesheet).toMatch(
+      /@media \(max-width: 1199px\)\s*\{\s*:root\s*\{\s*--page-gutter:\s*24px;/u
+    )
+    expect(stylesheet).toMatch(
+      /@media \(max-width: 959px\)\s*\{\s*:root\s*\{\s*--page-gutter:\s*16px;/u
+    )
+    expect(stylesheet).toMatch(
+      /\.page-shell--master-detail\s*\{[^}]*padding:\s*var\(--page-gutter\);/u
+    )
+  })
+
   it('renders a consistent page shell and scoped header', () => {
     render(
       <PageShell variant="dashboard">
@@ -188,8 +216,10 @@ describe('WorkspacePrimitives', () => {
     const onCancel = vi.fn()
     const { rerender } = render(
       <DestructiveConfirmActions
+        confirmAriaLabel="永久删除对象"
         confirmLabel="确认删除"
         confirming={false}
+        icon={<span data-testid="delete-icon">×</span>}
         onCancel={onCancel}
         onConfirm={onConfirm}
         onRequestConfirm={onRequestConfirm}
@@ -197,11 +227,16 @@ describe('WorkspacePrimitives', () => {
       />
     )
 
+    expect(screen.getByTestId('delete-icon').parentElement).toHaveAttribute(
+      'aria-hidden',
+      'true'
+    )
     fireEvent.click(screen.getByRole('button', { name: '删除' }))
     expect(onRequestConfirm).toHaveBeenCalledOnce()
 
     rerender(
       <DestructiveConfirmActions
+        confirmAriaLabel="永久删除对象"
         confirmLabel="确认删除"
         confirming
         message="删除此对象？"
@@ -211,11 +246,74 @@ describe('WorkspacePrimitives', () => {
         triggerLabel="删除"
       />
     )
-    expect(screen.getByRole('button', { name: '取消' })).toHaveFocus()
-    fireEvent.click(screen.getByRole('button', { name: '确认删除' }))
-    fireEvent.click(screen.getByRole('button', { name: '取消' }))
-    expect(onConfirm).toHaveBeenCalledOnce()
+    const dialog = screen.getByRole('alertdialog', {
+      name: '永久删除对象'
+    })
+    const cancelButton = screen.getByRole('button', { name: '取消' })
+    const confirmButton = screen.getByRole('button', {
+      name: '永久删除对象'
+    })
+    expect(dialog).toHaveAttribute('aria-modal', 'true')
+    expect(dialog).toHaveAccessibleDescription('删除此对象？')
+    expect(cancelButton).toHaveFocus()
+
+    fireEvent.keyDown(cancelButton, { key: 'Tab', shiftKey: true })
+    expect(confirmButton).toHaveFocus()
+    fireEvent.keyDown(confirmButton, { key: 'Tab' })
+    expect(cancelButton).toHaveFocus()
+
+    fireEvent.keyDown(cancelButton, { key: 'Escape' })
     expect(onCancel).toHaveBeenCalledOnce()
+    fireEvent.click(confirmButton)
+    expect(onConfirm).toHaveBeenCalledOnce()
+
+    rerender(
+      <DestructiveConfirmActions
+        confirmAriaLabel="永久删除对象"
+        confirmLabel="确认删除"
+        confirming={false}
+        onCancel={onCancel}
+        onConfirm={onConfirm}
+        onRequestConfirm={onRequestConfirm}
+        triggerLabel="删除"
+      />
+    )
+    expect(screen.getByRole('button', { name: '删除' })).toHaveFocus()
+  })
+
+  it('keeps focus on the dialog while destructive actions are disabled', () => {
+    const onCancel = vi.fn()
+    const { rerender } = render(
+      <DestructiveConfirmActions
+        confirmLabel="确认删除"
+        confirming={false}
+        onCancel={onCancel}
+        onConfirm={vi.fn()}
+        onRequestConfirm={vi.fn()}
+        triggerLabel="删除"
+      />
+    )
+
+    rerender(
+      <DestructiveConfirmActions
+        confirmLabel="正在删除"
+        confirming
+        disabled
+        onCancel={onCancel}
+        onConfirm={vi.fn()}
+        onRequestConfirm={vi.fn()}
+        triggerLabel="删除"
+      />
+    )
+
+    const dialog = screen.getByRole('alertdialog', {
+      name: '正在删除'
+    })
+    expect(dialog).toHaveFocus()
+    fireEvent.keyDown(dialog, { key: 'Tab' })
+    expect(dialog).toHaveFocus()
+    fireEvent.keyDown(dialog, { key: 'Escape' })
+    expect(onCancel).not.toHaveBeenCalled()
   })
 
   it.each([
diff --git a/src/renderer/src/WorkspacePrimitives.tsx b/src/renderer/src/WorkspacePrimitives.tsx
index ae1f2e5..e791243 100644
--- a/src/renderer/src/WorkspacePrimitives.tsx
+++ b/src/renderer/src/WorkspacePrimitives.tsx
@@ -6,6 +6,7 @@ import {
 } from 'lucide-react'
 import {
   useEffect,
+  useId,
   useRef,
   type KeyboardEvent,
   type ReactNode
@@ -326,30 +327,97 @@ export function DestructiveConfirmActions({
   triggerLabel: string
 }): React.JSX.Element {
   const cancelRef = useRef<HTMLButtonElement>(null)
+  const confirmRef = useRef<HTMLButtonElement>(null)
+  const dialogRef = useRef<HTMLDivElement>(null)
   const triggerRef = useRef<HTMLButtonElement>(null)
   const wasConfirming = useRef(confirming)
+  const shouldRestoreTrigger = useRef(false)
+  const titleId = useId()
+  const descriptionId = useId()
 
   useEffect(() => {
     if (confirming && !wasConfirming.current) {
-      cancelRef.current?.focus()
+      if (disabled) {
+        dialogRef.current?.focus()
+      } else {
+        cancelRef.current?.focus()
+      }
+    } else if (confirming && disabled) {
+      dialogRef.current?.focus()
     } else if (
+      confirming &&
+      !disabled &&
+      document.activeElement === dialogRef.current
+    ) {
+      cancelRef.current?.focus()
+    } else if (!confirming && wasConfirming.current) {
+      shouldRestoreTrigger.current = true
+    }
+
+    if (
       !confirming &&
-      wasConfirming.current &&
+      shouldRestoreTrigger.current &&
       !triggerRef.current?.disabled
     ) {
       triggerRef.current?.focus()
+      shouldRestoreTrigger.current = false
     }
     wasConfirming.current = confirming
-  }, [confirming])
+  }, [confirming, disabled])
 
   return confirming ? (
     <div
-      aria-label={confirmAriaLabel}
+      aria-describedby={descriptionId}
+      aria-labelledby={titleId}
       aria-live="assertive"
+      aria-modal="true"
       className="danger-confirm"
+      onKeyDown={(event) => {
+        if (event.key === 'Escape' && !disabled) {
+          event.preventDefault()
+          onCancel()
+          return
+        }
+        if (event.key !== 'Tab') {
+          return
+        }
+        if (disabled) {
+          event.preventDefault()
+          dialogRef.current?.focus()
+          return
+        }
+
+        const cancelButton = cancelRef.current
+        const confirmButton = confirmRef.current
+        if (
+          !cancelButton ||
+          !confirmButton ||
+          cancelButton.disabled ||
+          confirmButton.disabled
+        ) {
+          return
+        }
+
+        event.preventDefault()
+        const nextButton = event.shiftKey
+          ? document.activeElement === cancelButton
+            ? confirmButton
+            : cancelButton
+          : document.activeElement === confirmButton
+            ? cancelButton
+            : confirmButton
+        nextButton.focus()
+      }}
+      ref={dialogRef}
       role="alertdialog"
+      tabIndex={-1}
     >
-      {message && <span>{message}</span>}
+      <span className="sr-only" id={titleId}>
+        {confirmAriaLabel ?? confirmLabel}
+      </span>
+      <span className={message ? undefined : 'sr-only'} id={descriptionId}>
+        {message ?? `确认${triggerLabel}操作。`}
+      </span>
       <button
         aria-label={cancelAriaLabel}
         className="secondary-button"
@@ -365,6 +433,7 @@ export function DestructiveConfirmActions({
         className="danger-button"
         disabled={disabled}
         onClick={onConfirm}
+        ref={confirmRef}
         type="button"
       >
         {confirmLabel}
@@ -379,7 +448,7 @@ export function DestructiveConfirmActions({
       ref={triggerRef}
       type="button"
     >
-      {icon}
+      {icon && <span aria-hidden="true">{icon}</span>}
       {triggerLabel}
     </button>
   )
diff --git a/src/renderer/src/activity-store.test.ts b/src/renderer/src/activity-store.test.ts
index 4e609c5..edb4bbe 100644
--- a/src/renderer/src/activity-store.test.ts
+++ b/src/renderer/src/activity-store.test.ts
@@ -15,6 +15,7 @@ function makeRecord(index: number): ActivityRecord {
     id: `activity-${index}`,
     conversationId: 'conversation-1',
     requestId: 'request-1',
+    scope: { kind: 'global' },
     kind: 'tool',
     title: `工具调用 ${index}`,
     detail: '读取文件',
@@ -55,6 +56,41 @@ describe('activity-store', () => {
     expect(loadActivityRecords()).toEqual([validRecord])
   })
 
+  it('loads legacy records with an explicit unavailable scope', () => {
+    const { scope, ...legacyRecord } = makeRecord(1)
+    void scope
+    localStorage.setItem(
+      ACTIVITY_STORAGE_KEY,
+      JSON.stringify([legacyRecord])
+    )
+
+    expect(loadActivityRecords()).toEqual([
+      expect.objectContaining({
+        id: legacyRecord.id,
+        scope: { kind: 'unavailable' }
+      })
+    ])
+  })
+
+  it('rejects malformed project snapshots from untrusted storage', () => {
+    const record = makeRecord(1)
+    localStorage.setItem(
+      ACTIVITY_STORAGE_KEY,
+      JSON.stringify([
+        {
+          ...record,
+          scope: {
+            kind: 'project',
+            projectId: 'project-1',
+            projectName: 'x'.repeat(121)
+          }
+        }
+      ])
+    )
+
+    expect(loadActivityRecords()).toEqual([])
+  })
+
   it('persists no more than the record limit', () => {
     const records = Array.from(
       { length: MAX_ACTIVITY_RECORDS + 1 },
@@ -102,10 +138,32 @@ describe('activity-store', () => {
       .toMatchObject({
         id: first.id,
         createdAt: first.createdAt,
+        scope: first.scope,
         status: 'failed'
       })
   })
 
+  it('keeps the original scope snapshot when a call is updated', () => {
+    const first: ActivityRecord = {
+      ...makeRecord(1),
+      callId: 'call-1',
+      scope: {
+        kind: 'project',
+        projectId: 'project-1',
+        projectName: '原项目名称'
+      },
+      status: 'running'
+    }
+
+    expect(
+      upsertActivityRecord([first], {
+        ...first,
+        scope: { kind: 'global' },
+        status: 'completed'
+      })[0]?.scope
+    ).toEqual(first.scope)
+  })
+
   it('persists and upserts Subagent state transitions', () => {
     const queued: ActivityRecord = {
       ...makeRecord(1),
diff --git a/src/renderer/src/activity-store.ts b/src/renderer/src/activity-store.ts
index 7d7fc96..ef4900b 100644
--- a/src/renderer/src/activity-store.ts
+++ b/src/renderer/src/activity-store.ts
@@ -7,6 +7,7 @@ export const MAX_ACTIVITY_DETAIL_LENGTH = 4_000
 const MAX_STORED_JSON_LENGTH = 2_000_000
 const MAX_ID_LENGTH = 256
 const MAX_TITLE_LENGTH = 240
+const MAX_PROJECT_NAME_LENGTH = 120
 
 const activityKinds = [
   'request',
@@ -30,6 +31,10 @@ export type ActivityRecord = {
   conversationId: string
   requestId: string
   callId?: string
+  scope:
+    | { kind: 'global' }
+    | { kind: 'project'; projectId: string; projectName: string }
+    | { kind: 'unavailable' }
   kind: (typeof activityKinds)[number]
   title: string
   detail: string
@@ -57,30 +62,82 @@ function isBoundedString(
   )
 }
 
-function isActivityRecord(value: unknown): value is ActivityRecord {
+function parseActivityScope(
+  value: unknown
+): ActivityRecord['scope'] | undefined {
   if (typeof value !== 'object' || value === null || Array.isArray(value)) {
-    return false
+    return undefined
+  }
+  const candidate = value as Record<string, unknown>
+  if (candidate.kind === 'global') {
+    return { kind: 'global' }
+  }
+  if (candidate.kind === 'unavailable') {
+    return { kind: 'unavailable' }
+  }
+  if (
+    candidate.kind === 'project' &&
+    isBoundedString(candidate.projectId, MAX_ID_LENGTH) &&
+    isBoundedString(candidate.projectName, MAX_PROJECT_NAME_LENGTH)
+  ) {
+    return {
+      kind: 'project',
+      projectId: candidate.projectId,
+      projectName: candidate.projectName
+    }
+  }
+  return undefined
+}
+
+function parseActivityRecord(value: unknown): ActivityRecord | undefined {
+  if (typeof value !== 'object' || value === null || Array.isArray(value)) {
+    return undefined
   }
 
   const candidate = value as Record<string, unknown>
-  return (
-    isBoundedString(candidate.id, MAX_ID_LENGTH) &&
-    isBoundedString(candidate.conversationId, MAX_ID_LENGTH) &&
-    isBoundedString(candidate.requestId, MAX_ID_LENGTH) &&
-    (candidate.callId === undefined ||
-      isBoundedString(candidate.callId, MAX_ID_LENGTH)) &&
-    activityKinds.some((kind) => kind === candidate.kind) &&
-    isBoundedString(candidate.title, MAX_TITLE_LENGTH) &&
-    isBoundedString(
+  if (
+    !isBoundedString(candidate.id, MAX_ID_LENGTH) ||
+    !isBoundedString(candidate.conversationId, MAX_ID_LENGTH) ||
+    !isBoundedString(candidate.requestId, MAX_ID_LENGTH) ||
+    (candidate.callId !== undefined &&
+      !isBoundedString(candidate.callId, MAX_ID_LENGTH)) ||
+    !activityKinds.some((kind) => kind === candidate.kind) ||
+    !isBoundedString(candidate.title, MAX_TITLE_LENGTH) ||
+    !isBoundedString(
       candidate.detail,
       MAX_ACTIVITY_DETAIL_LENGTH,
       true
-    ) &&
-    activityStatuses.some((status) => status === candidate.status) &&
-    typeof candidate.createdAt === 'number' &&
-    Number.isFinite(candidate.createdAt) &&
-    candidate.createdAt >= 0
-  )
+    ) ||
+    !activityStatuses.some((status) => status === candidate.status) ||
+    typeof candidate.createdAt !== 'number' ||
+    !Number.isFinite(candidate.createdAt) ||
+    candidate.createdAt < 0
+  ) {
+    return undefined
+  }
+
+  const scope =
+    candidate.scope === undefined
+      ? { kind: 'unavailable' as const }
+      : parseActivityScope(candidate.scope)
+  if (!scope) {
+    return undefined
+  }
+
+  return {
+    id: candidate.id,
+    conversationId: candidate.conversationId,
+    requestId: candidate.requestId,
+    ...(candidate.callId === undefined
+      ? {}
+      : { callId: candidate.callId }),
+    scope,
+    kind: candidate.kind as ActivityRecord['kind'],
+    title: candidate.title,
+    detail: candidate.detail,
+    status: candidate.status as ActivityRecord['status'],
+    createdAt: candidate.createdAt
+  }
 }
 
 export function upsertActivityRecord(
@@ -109,7 +166,8 @@ export function upsertActivityRecord(
     {
       ...incoming,
       id: existing.id,
-      createdAt: existing.createdAt
+      createdAt: existing.createdAt,
+      scope: existing.scope
     },
     ...records.filter((_, index) => index !== existingIndex)
   ].slice(0, MAX_ACTIVITY_RECORDS)
@@ -200,8 +258,9 @@ export function loadActivityRecords(
 
     const records: ActivityRecord[] = []
     for (const candidate of parsed) {
-      if (isActivityRecord(candidate)) {
-        records.push(candidate)
+      const record = parseActivityRecord(candidate)
+      if (record) {
+        records.push(record)
       }
       if (records.length === MAX_ACTIVITY_RECORDS) {
         break
@@ -227,8 +286,9 @@ export function saveActivityRecords(
 
   const safeRecords: ActivityRecord[] = []
   for (const record of records) {
-    if (isActivityRecord(record)) {
-      safeRecords.push(record)
+    const safeRecord = parseActivityRecord(record)
+    if (safeRecord) {
+      safeRecords.push(safeRecord)
     }
     if (safeRecords.length === MAX_ACTIVITY_RECORDS) {
       break
diff --git a/src/renderer/src/styles.css b/src/renderer/src/styles.css
index 42f664e..ce27641 100644
--- a/src/renderer/src/styles.css
+++ b/src/renderer/src/styles.css
@@ -34,7 +34,7 @@
   --space-3: 12px;
   --space-4: 16px;
   --space-6: 24px;
-  --page-gutter: clamp(16px, 2vw, 28px);
+  --page-gutter: 32px;
   --content-reading: 820px;
   --content-standard: 960px;
   --content-dashboard: 1040px;
@@ -60,6 +60,18 @@
   text-rendering: optimizeLegibility;
 }
 
+@media (max-width: 1199px) {
+  :root {
+    --page-gutter: 24px;
+  }
+}
+
+@media (max-width: 959px) {
+  :root {
+    --page-gutter: 16px;
+  }
+}
+
 .magic-notes-page {
   display: flex;
   min-width: 0;
@@ -785,8 +797,9 @@ button {
 
 button:focus-visible,
 input:focus-visible,
+select:focus-visible,
 textarea:focus-visible {
-  outline: 2px solid #1677ff;
+  outline: 2px solid var(--accent);
   outline-offset: 2px;
 }
 
@@ -819,6 +832,10 @@ textarea:focus-visible {
   padding-left: 0;
 }
 
+.sidebar-backdrop {
+  display: none;
+}
+
 .brand {
   display: flex;
   align-items: center;
@@ -1330,6 +1347,11 @@ textarea:focus-visible {
   outline-offset: -2px;
 }
 
+.window-control > svg,
+.icon-button > svg {
+  pointer-events: none;
+}
+
 .icon-button {
   display: grid;
   width: 34px;
@@ -1337,18 +1359,18 @@ textarea:focus-visible {
   place-items: center;
   border-radius: 9px;
   background: transparent;
-  color: #595959;
+  color: var(--text-secondary);
   cursor: pointer;
 }
 
 .icon-button:hover {
-  background: #e6f4ff;
-  color: #1677ff;
+  background: var(--accent-subtle);
+  color: var(--accent);
 }
 
 .icon-button--active {
-  background: #e6f4ff;
-  color: #1677ff;
+  background: var(--accent-subtle);
+  color: var(--accent);
 }
 
 .assistant-sidebar {
@@ -3858,6 +3880,7 @@ textarea:focus-visible {
 }
 
 .settings-panel__header {
+  position: relative;
   display: flex;
   align-items: center;
   padding: 22px 24px 18px;
@@ -3868,6 +3891,25 @@ textarea:focus-visible {
   flex: 1;
 }
 
+.settings-panel__header .page-header {
+  position: relative;
+  width: 100%;
+}
+
+.settings-panel__header .page-header__content {
+  padding-right: 44px;
+}
+
+.settings-panel__header
+  .page-header:not(.page-header--compact)
+  .page-header__actions {
+  position: absolute;
+  top: 0;
+  right: 0;
+  width: auto;
+  justify-content: flex-end;
+}
+
 .settings-panel__header .eyebrow {
   margin-bottom: 5px;
 }
@@ -5050,17 +5092,17 @@ details.settings-section > :not(summary) + :not(summary) {
 .capability-card {
   display: flex;
   flex-direction: column;
-  padding: 12px;
-  border: 1px solid #e8e8e8;
-  border-radius: 8px;
-  background: #fff;
-  gap: 8px;
+  padding: var(--space-3);
+  border: 1px solid var(--border-default);
+  border-radius: var(--radius-card);
+  background: var(--surface-raised);
+  gap: var(--space-2);
 }
 
 .capability-card__header {
   display: flex;
   align-items: flex-start;
-  gap: 12px;
+  gap: var(--space-3);
 }
 
 .capability-card__header > div:first-child {
@@ -5071,30 +5113,30 @@ details.settings-section > :not(summary) + :not(summary) {
 }
 
 .capability-card strong {
-  color: #1f1f1f;
-  font-size: 11px;
+  color: var(--text-primary);
+  font-size: var(--font-body);
 }
 
 .capability-card small,
 .runtime-assignments small {
-  color: #8c8c8c;
-  font-size: 9px;
+  color: var(--text-muted);
+  font-size: var(--font-caption);
 }
 
 .capability-card p {
   margin: 0;
-  color: #595959;
-  font-size: 10px;
+  color: var(--text-secondary);
+  font-size: var(--font-caption);
   line-height: 1.55;
 }
 
 .capability-card code {
-  padding: 7px 8px;
-  border-radius: 6px;
+  padding: var(--space-2);
+  border-radius: var(--radius-control);
   overflow: hidden;
-  background: #f5f5f5;
-  color: #595959;
-  font-size: 9px;
+  background: var(--surface-subtle);
+  color: var(--text-secondary);
+  font-size: var(--font-caption);
   text-overflow: ellipsis;
   white-space: nowrap;
 }
@@ -5111,9 +5153,69 @@ details.settings-section > :not(summary) + :not(summary) {
 
 .capability-switch,
 .runtime-assignments label {
-  color: #595959;
-  font-size: 9px;
-  gap: 4px;
+  color: var(--text-secondary);
+  font-size: var(--font-caption);
+  gap: var(--space-1);
+}
+
+.toggle-row {
+  display: flex;
+  min-height: 36px;
+  align-items: center;
+  justify-content: space-between;
+  padding-top: var(--space-2);
+  border-top: 1px solid var(--border-subtle);
+  color: var(--text-secondary);
+  cursor: pointer;
+  font-size: var(--font-body);
+  gap: var(--space-3);
+}
+
+.toggle-row input {
+  position: relative;
+  width: 38px;
+  height: 22px;
+  padding: 0;
+  border: 1px solid var(--border-control);
+  border-radius: 999px;
+  appearance: none;
+  background: var(--surface-muted);
+  cursor: pointer;
+  flex: 0 0 auto;
+  transition:
+    border-color var(--motion-fast) ease-out,
+    background-color var(--motion-fast) ease-out;
+}
+
+.toggle-row input::after {
+  position: absolute;
+  width: 16px;
+  height: 16px;
+  border-radius: 50%;
+  background: var(--surface-raised);
+  box-shadow: 0 1px 2px rgb(0 0 0 / 24%);
+  content: '';
+  left: 2px;
+  top: 2px;
+  transition: transform var(--motion-fast) ease-out;
+}
+
+.toggle-row input:checked {
+  border-color: var(--accent-solid);
+  background: var(--accent-solid);
+}
+
+.toggle-row input:checked::after {
+  transform: translateX(16px);
+}
+
+.toggle-row input:disabled {
+  cursor: not-allowed;
+  opacity: 0.6;
+}
+
+.toggle-row:has(input:disabled) {
+  cursor: not-allowed;
 }
 
 .runtime-assignments {
@@ -5770,7 +5872,7 @@ details.settings-section > :not(summary) + :not(summary) {
 }
 
 .page-shell--master-detail {
-  padding: clamp(14px, 2vw, 28px);
+  padding: var(--page-gutter);
   overflow-x: hidden;
   container-type: inline-size;
 }
@@ -5886,7 +5988,9 @@ details.settings-section > :not(summary) + :not(summary) {
 
 .page-tabs {
   display: flex;
-  flex-wrap: wrap;
+  max-width: 100%;
+  overflow-x: auto;
+  flex-wrap: nowrap;
   gap: var(--space-1);
 }
 
@@ -5900,9 +6004,11 @@ details.settings-section > :not(summary) + :not(summary) {
   background: transparent;
   color: var(--text-secondary);
   cursor: pointer;
+  flex: 0 0 auto;
   font-size: 11px;
   font-weight: 650;
   gap: 6px;
+  white-space: nowrap;
 }
 
 .page-tabs__tab:hover {
@@ -7876,15 +7982,6 @@ details.settings-section > :not(summary) + :not(summary) {
     grid-template-columns: 1fr;
   }
 
-  .heartbeat-center > .page-tabs {
-    display: grid;
-    grid-template-columns: 1fr 1fr;
-  }
-
-  .heartbeat-center > .page-tabs .page-tabs__tab {
-    justify-content: center;
-  }
-
   .heartbeat-center__trend-row {
     grid-template-columns: 70px minmax(0, 1fr) 18px;
   }
@@ -7999,6 +8096,32 @@ details.settings-section > :not(summary) + :not(summary) {
   }
 }
 
+@media (max-width: 899px) {
+  .sidebar {
+    position: absolute;
+    z-index: 40;
+    top: 0;
+    bottom: 0;
+    left: 0;
+    width: min(278px, calc(100vw - 52px));
+    box-shadow: 12px 0 30px rgb(0 0 0 / 14%);
+  }
+
+  .sidebar--closed {
+    width: 0;
+    box-shadow: none;
+  }
+
+  .sidebar-backdrop {
+    position: absolute;
+    z-index: 35;
+    display: block;
+    border: 0;
+    background: var(--overlay-backdrop);
+    inset: 0;
+  }
+}
+
 @media (max-width: 719px) {
   .assistant-sidebar__resize-handle {
     display: none;
@@ -8007,7 +8130,49 @@ details.settings-section > :not(summary) + :not(summary) {
 
 @media (max-width: 720px) {
   .workspace-panel-scroll {
-    padding: 20px;
+    padding: var(--page-gutter);
+  }
+
+  .settings-page .settings-panel__body {
+    display: flex;
+    padding: var(--space-4);
+    overflow: hidden;
+    flex-direction: column;
+    gap: var(--space-3);
+  }
+
+  .settings-page .settings-tabs {
+    display: flex;
+    width: 100%;
+    min-height: auto;
+    padding: var(--space-1);
+    overflow-x: auto;
+    overflow-y: hidden;
+    flex: 0 0 auto;
+    flex-direction: row;
+    scrollbar-gutter: auto;
+    scrollbar-color: var(--border-control) transparent;
+    scrollbar-width: thin;
+  }
+
+  .settings-page .settings-tabs button {
+    min-width: max-content;
+    min-height: 40px;
+    padding: var(--space-2) var(--space-3);
+    align-items: center;
+    text-align: center;
+  }
+
+  .settings-page .settings-tabs button small {
+    display: none;
+  }
+
+  .settings-page .settings-panel__content {
+    width: 100%;
+    min-height: 0;
+    padding-right: 0;
+    overflow-y: auto;
+    flex: 1;
   }
 
   .agent-runtime-navigation {
@@ -8072,7 +8237,7 @@ details.settings-section > :not(summary) + :not(summary) {
 
 @media (max-width: 520px) {
   .workspace-panel-scroll {
-    padding: 16px;
+    padding: var(--page-gutter);
   }
 
   .model-connection-add {
@@ -8094,15 +8259,6 @@ details.settings-section > :not(summary) + :not(summary) {
     grid-template-columns: 1fr;
   }
 
-  .heartbeat-center > .page-tabs {
-    display: grid;
-    grid-template-columns: 1fr 1fr;
-  }
-
-  .heartbeat-center > .page-tabs .page-tabs__tab {
-    justify-content: center;
-  }
-
   .heartbeat-center__trend-row {
     grid-template-columns: 70px minmax(0, 1fr) 18px;
   }
diff --git a/src/shared/application-settings-contracts.ts b/src/shared/application-settings-contracts.ts
index af4ecb0..865dd36 100644
--- a/src/shared/application-settings-contracts.ts
+++ b/src/shared/application-settings-contracts.ts
@@ -2,14 +2,25 @@ import { z } from 'zod'
 
 export const applicationSettingsSchema = z
   .object({
-    checkUpdatesOnStartup: z.boolean()
+    checkUpdatesOnStartup: z.boolean(),
+    magicNotesEnabled: z.boolean()
   })
   .strict()
 
+export const applicationSettingsUpdateSchema = applicationSettingsSchema
+  .partial()
+  .refine((input) => Object.keys(input).length > 0, {
+    message: 'At least one application setting is required'
+  })
+
 export type ApplicationSettings = z.infer<
   typeof applicationSettingsSchema
 >
 
+export type ApplicationSettingsUpdate = z.infer<
+  typeof applicationSettingsUpdateSchema
+>
+
 export type VersionCheckFile = {
   name: string
   size: number
diff --git a/src/shared/contracts.ts b/src/shared/contracts.ts
index 0319db7..bcfed62 100644
--- a/src/shared/contracts.ts
+++ b/src/shared/contracts.ts
@@ -58,6 +58,7 @@ import type {
 } from './channel-settings-contracts'
 import type {
   ApplicationSettings,
+  ApplicationSettingsUpdate,
   VersionCheckResult
 } from './application-settings-contracts'
 import type {
@@ -981,7 +982,7 @@ export type DesktopApi = {
   updates?: {
     getSettings: () => Promise<ApplicationSettings>
     updateSettings: (
-      input: ApplicationSettings
+      input: ApplicationSettingsUpdate
     ) => Promise<ApplicationSettings>
     check: () => Promise<VersionCheckResult>
     openReleasePage: () => Promise<void>
diff --git a/src/shared/remote-channel-contracts.ts b/src/shared/remote-channel-contracts.ts
index e7daafc..423556d 100644
--- a/src/shared/remote-channel-contracts.ts
+++ b/src/shared/remote-channel-contracts.ts
@@ -5,6 +5,8 @@ export const remoteChannelActivitySchema = z
   .object({
     requestId: z.string().uuid(),
     conversationId: z.string().uuid(),
+    projectId: z.string().uuid(),
+    projectName: z.string().trim().min(1).max(120),
     channel: projectChannelSchema,
     kind: z.enum(['request', 'tool', 'result']),
     title: z.string().trim().min(1).max(240),