feat: preserve pages and compress context

src/main/agent/context-compression.test.ts

@@ -72,19 +72,37 @@ describe('context compression planning', () => {
 
   it('uses an optional model context limit as an earlier trigger', () => {
     const history = [
-      { role: 'user' as const, content: 'a'.repeat(14_000) },
+      { role: 'user' as const, content: 'a'.repeat(16_000) },
-      { role: 'assistant' as const, content: 'b'.repeat(14_000) },
+      { role: 'assistant' as const, content: 'b'.repeat(16_000) },
-      { role: 'user' as const, content: 'c'.repeat(14_000) },
+      { role: 'user' as const, content: 'c'.repeat(16_000) },
-      { role: 'assistant' as const, content: 'd'.repeat(14_000) }
+      { role: 'assistant' as const, content: 'd'.repeat(16_000) }
     ]
     const plan = planContextCompression({
       history,
       prompt: 'Continue',
       settings: compressionSettings(),
-      contextWindowTokens: 30_000
+      contextWindowTokens: 32_000
     })
 
-    expect(plan?.effectiveTriggerTokens).toBe(18_000)
+    expect(plan?.effectiveTriggerTokens).toBe(20_000)
+    expect(plan?.earlierMessages.length).toBeGreaterThan(0)
+  })
+
+  it('defensively clamps legacy undersized context limits', () => {
+    const history = [
+      { role: 'user' as const, content: 'a'.repeat(40_000) },
+      { role: 'assistant' as const, content: 'b'.repeat(40_000) },
+      { role: 'user' as const, content: 'c'.repeat(40_000) },
+      { role: 'assistant' as const, content: 'd'.repeat(40_000) }
+    ]
+    const plan = planContextCompression({
+      history,
+      prompt: 'Continue',
+      settings: compressionSettings(),
+      contextWindowTokens: 10_000
+    })
+
+    expect(plan?.effectiveTriggerTokens).toBe(20_000)
     expect(plan?.earlierMessages.length).toBeGreaterThan(0)
   })
 })

src/main/agent/context-compression.ts

@@ -1,4 +1,14 @@
 import type { ContextCompressionSettings } from '../../shared/contracts'
+import {
+  estimateContextInputTokens,
+  estimateMessagesTokens,
+  getEffectiveContextTriggerTokens
+} from '../../shared/context-window'
+
+export {
+  estimateMessagesTokens,
+  estimateTextTokens
+} from '../../shared/context-window'
 
 export type CompressibleConversationMessage = {
   role: 'user' | 'assistant'
@@ -12,34 +22,6 @@ export type ContextCompressionPlan = {
   effectiveTriggerTokens: number
 }
 
-const reservedOutputAndSafetyTokens = 12_000
-const estimatedRequestOverheadTokens = 4_000
-
-export function estimateTextTokens(value: string): number {
-  let asciiCharacters = 0
-  let nonAsciiCharacters = 0
-  for (const character of value) {
-    if (character.codePointAt(0)! <= 0x7f) {
-      asciiCharacters += 1
-    } else {
-      nonAsciiCharacters += 1
-    }
-  }
-  return Math.max(
-    1,
-    Math.ceil(asciiCharacters / 4 + nonAsciiCharacters)
-  )
-}
-
-export function estimateMessagesTokens(
-  messages: readonly CompressibleConversationMessage[]
-): number {
-  return messages.reduce(
-    (total, message) => total + estimateTextTokens(message.content) + 4,
-    0
-  )
-}
-
 function groupConversationTurns(
   messages: readonly CompressibleConversationMessage[]
 ): CompressibleConversationMessage[][] {
@@ -61,24 +43,19 @@ function groupConversationTurns(
 export function planContextCompression(input: {
   history: readonly CompressibleConversationMessage[]
   prompt: string
+  summaryTokens?: number
   settings: ContextCompressionSettings
   contextWindowTokens?: number
 }): ContextCompressionPlan | undefined {
-  const estimatedInputTokens =
+  const estimatedInputTokens = estimateContextInputTokens({
-    estimateMessagesTokens(input.history) +
+    history: input.history,
-    estimateTextTokens(input.prompt) +
+    prompt: input.prompt,
-    estimatedRequestOverheadTokens
+    summaryTokens: input.summaryTokens
-  const contextLimitedTrigger =
+  })
-    input.contextWindowTokens === undefined
+  const effectiveTriggerTokens = getEffectiveContextTriggerTokens({
-      ? input.settings.triggerTokens
+    triggerTokens: input.settings.triggerTokens,
-      : Math.max(
+    contextWindowTokens: input.contextWindowTokens
-          8_000,
+  })
-          input.contextWindowTokens - reservedOutputAndSafetyTokens
-        )
-  const effectiveTriggerTokens = Math.min(
-    input.settings.triggerTokens,
-    contextLimitedTrigger
-  )
   if (estimatedInputTokens < effectiveTriggerTokens) {
     return undefined
   }

src/main/agent/model-runtime.test.ts

@@ -379,9 +379,30 @@ describe('ModelAgentRuntime', () => {
     expect(answerMessages).toContain('new-user-')
     expect(answerMessages).not.toContain('old-user-')
     expect(events).toContainEqual(
+      expect.objectContaining({
+        type: 'context-compression',
+        state: 'started',
+        estimatedBeforeTokens: expect.any(Number)
+      })
+    )
+    expect(events).toContainEqual(
+      expect.objectContaining({
+        type: 'context-compression',
+        state: 'completed',
+        estimatedAfterTokens: expect.any(Number)
+      })
+    )
+    expect(events).toContainEqual(
+      expect.objectContaining({
+        type: 'context-metrics',
+        coveredMessageCount: 4,
+        summaryTokens: expect.any(Number)
+      })
+    )
+    expect(events).not.toContainEqual(
       expect.objectContaining({
         type: 'status',
-        message: '较早的对话已压缩，正在生成回答'
+        message: '正在准备直连模型上下文'
       })
     )
     expect(events).toContainEqual(

src/main/agent/model-runtime.ts

@@ -42,8 +42,13 @@ import {
 import { readBoundedResponseText } from './bounded-response'
 import {
   formatConversationForSummary,
-  planContextCompression
+  planContextCompression,
+  estimateMessagesTokens
 } from './context-compression'
+import {
+  estimateContextInputTokens,
+  getEffectiveContextTriggerTokens
+} from '../../shared/context-window'
 
 type ConversationMessage = {
   role: 'user' | 'assistant'
@@ -1784,23 +1789,19 @@ export class ModelAgentRuntime implements AgentRuntime {
     return { summary: summary.trim(), usageEvents }
   }
 
-  private async prepareCompressedRequest(
+  private async *prepareCompressedRequest(
     request: AgentExecutionRequest,
     signal: AbortSignal
-  ): Promise<{
+  ): AsyncGenerator<RuntimeEvent, {
     request: AgentExecutionRequest
     compressed: boolean
-    usageEvents: RuntimeModelUsageEvent[]
+  }, void> {
-  }> {
     const compression = this.options.contextCompression
-    if (
+    if (!compression) {
-      !compression?.settings.enabled ||
+      return { request, compressed: false }
-      !request.history?.length
-    ) {
-      return { request, compressed: false, usageEvents: [] }
     }
 
-    const history = request.history
+    const history = request.history ?? []
     let state = this.conversationSummaries.get(request.conversationId)
     if (
       state &&
@@ -1815,13 +1816,42 @@ export class ModelAgentRuntime implements AgentRuntime {
     const remainingHistory = history.slice(
       state?.coveredMessageCount ?? 0
     )
+    const requestPrompt = [
+      request.trustedInstructions ?? '',
+      request.prompt
+    ].join('\n')
+    const currentSummaryTokens = state
+      ? estimateMessagesTokens(this.summaryHistory(state.summary))
+      : 0
+    const effectiveTriggerTokens =
+      getEffectiveContextTriggerTokens({
+        triggerTokens: compression.settings.triggerTokens,
+        contextWindowTokens: compression.contextWindowTokens
+      })
+    const estimatedInputTokens = estimateContextInputTokens({
+      history: remainingHistory,
+      prompt: requestPrompt,
+      summaryTokens: currentSummaryTokens
+    })
+    yield {
+      requestId: request.requestId,
+      type: 'context-metrics',
+      estimatedInputTokens,
+      effectiveTriggerTokens,
+      contextWindowTokens: compression.contextWindowTokens,
+      compressionEnabled: compression.settings.enabled,
+      recentRawTokens: compression.settings.recentRawTokens,
+      coveredMessageCount: state?.coveredMessageCount ?? 0,
+      summaryTokens: currentSummaryTokens
+    }
+    if (!compression.settings.enabled || history.length === 0) {
+      return { request, compressed: false }
+    }
+
     const plan = planContextCompression({
       history: remainingHistory,
-      prompt: [
+      prompt: requestPrompt,
-        state?.summary ?? '',
+      summaryTokens: currentSummaryTokens,
-        request.trustedInstructions ?? '',
-        request.prompt
-      ].join('\n'),
       settings: compression.settings,
       contextWindowTokens: compression.contextWindowTokens
     })
@@ -1836,20 +1866,29 @@ export class ModelAgentRuntime implements AgentRuntime {
               ]
             },
             compressed: false,
-            usageEvents: []
           }
-        : { request, compressed: false, usageEvents: [] }
+        : { request, compressed: false }
     }
 
+    const coveredMessageCount =
+      (state?.coveredMessageCount ?? 0) +
+      plan.earlierMessages.length
+    yield {
+      requestId: request.requestId,
+      type: 'context-compression',
+      state: 'started',
+      estimatedBeforeTokens: plan.estimatedInputTokens,
+      effectiveTriggerTokens: plan.effectiveTriggerTokens,
+      contextWindowTokens: compression.contextWindowTokens,
+      recentRawTokens: compression.settings.recentRawTokens,
+      coveredMessageCount
+    }
     const summarized = await this.summarizeEarlierHistory(
       request,
       plan.earlierMessages,
       state?.summary,
       signal
     )
-    const coveredMessageCount =
-      (state?.coveredMessageCount ?? 0) +
-      plan.earlierMessages.length
     state = {
       coveredMessageCount,
       coveredHistoryDigest: this.historyDigest(
@@ -1858,6 +1897,40 @@ export class ModelAgentRuntime implements AgentRuntime {
       summary: summarized.summary
     }
     this.conversationSummaries.set(request.conversationId, state)
+    for (const usageEvent of summarized.usageEvents) {
+      yield usageEvent
+    }
+    const summaryTokens = estimateMessagesTokens(
+      this.summaryHistory(state.summary)
+    )
+    const estimatedAfterTokens = estimateContextInputTokens({
+      history: plan.recentMessages,
+      prompt: requestPrompt,
+      summaryTokens
+    })
+    yield {
+      requestId: request.requestId,
+      type: 'context-compression',
+      state: 'completed',
+      estimatedBeforeTokens: plan.estimatedInputTokens,
+      estimatedAfterTokens,
+      effectiveTriggerTokens: plan.effectiveTriggerTokens,
+      contextWindowTokens: compression.contextWindowTokens,
+      recentRawTokens: compression.settings.recentRawTokens,
+      coveredMessageCount,
+      summaryTokens
+    }
+    yield {
+      requestId: request.requestId,
+      type: 'context-metrics',
+      estimatedInputTokens: estimatedAfterTokens,
+      effectiveTriggerTokens: plan.effectiveTriggerTokens,
+      contextWindowTokens: compression.contextWindowTokens,
+      compressionEnabled: true,
+      recentRawTokens: compression.settings.recentRawTokens,
+      coveredMessageCount,
+      summaryTokens
+    }
     return {
       request: {
         ...request,
@@ -1866,8 +1939,7 @@ export class ModelAgentRuntime implements AgentRuntime {
           ...plan.recentMessages
         ]
       },
-      compressed: true,
+      compressed: true
-      usageEvents: summarized.usageEvents
     }
   }
 
@@ -2791,29 +2863,21 @@ export class ModelAgentRuntime implements AgentRuntime {
       throw new Error('当前模型连接未启用图像输入')
     }
 
-    if (
+    const preparation = this.prepareCompressedRequest(
-      this.options.contextCompression?.settings.enabled &&
-      request.history?.length
-    ) {
-      yield {
-        requestId: request.requestId,
-        type: 'status',
-        message: '正在准备直连模型上下文'
-      }
-    }
-    const prepared = await this.prepareCompressedRequest(
       request,
       signal
     )
-    for (const usageEvent of prepared.usageEvents) {
+    let prepared: {
-      yield usageEvent
+      request: AgentExecutionRequest
+      compressed: boolean
     }
-    if (prepared.compressed) {
+    while (true) {
-      yield {
+      const result = await preparation.next()
-        requestId: request.requestId,
+      if (result.done) {
-        type: 'status',
+        prepared = result.value
-        message: '较早的对话已压缩，正在生成回答'
+        break
       }
+      yield result.value
     }
     const executionRequest = prepared.request
 

src/main/agent/runtime-e2e.manual.test.ts

@@ -226,10 +226,9 @@ describe.runIf(enabled)('runtime end-to-end', () => {
         contextCompression: {
           settings: {
             ...defaultContextCompressionSettings,
-            enabled: true,
+            enabled: true
-            triggerTokens: 8_000,
+          },
-            recentRawTokens: 4_000
+          contextWindowTokens: 32_000
-          }
         }
       })
       const events: RuntimeEvent[] = []
@@ -248,7 +247,7 @@ describe.runIf(enabled)('runtime end-to-end', () => {
                 content: [
                   'The project codename is ORBIT-739.',
                   'Background notes:',
-                  'alpha '.repeat(1_200)
+                  'alpha '.repeat(5_000)
                 ].join('\n')
               },
               {
@@ -256,7 +255,7 @@ describe.runIf(enabled)('runtime end-to-end', () => {
                 content: [
                   'I will remember the project codename.',
                   'Acknowledgement notes:',
-                  'gamma '.repeat(1_000)
+                  'gamma '.repeat(4_000)
                 ].join('\n')
               },
               {
@@ -264,7 +263,7 @@ describe.runIf(enabled)('runtime end-to-end', () => {
                 content: [
                   'The deploy region is AP-SOUTH-7.',
                   'Recent notes:',
-                  'beta '.repeat(900)
+                  'beta '.repeat(3_000)
                 ].join('\n')
               },
               {
@@ -289,8 +288,15 @@ describe.runIf(enabled)('runtime end-to-end', () => {
         .join('')
       expect(events).toContainEqual(
         expect.objectContaining({
-          type: 'status',
+          type: 'context-compression',
-          message: '较早的对话已压缩，正在生成回答'
+          state: 'started'
+        })
+      )
+      expect(events).toContainEqual(
+        expect.objectContaining({
+          type: 'context-compression',
+          state: 'completed',
+          estimatedAfterTokens: expect.any(Number)
         })
       )
       expect(events).toContainEqual(

src/main/runtime-settings-store.test.ts

@@ -156,6 +156,61 @@ describe('RuntimeSettingsStore', () => {
     })
   })
 
+  it('rejects undersized model context windows and repairs legacy values', async () => {
+    const { filePath, store } = await createStore()
+    const profileId = '00000000-0000-4000-8000-000000000062'
+    const profile = {
+      id: profileId,
+      name: 'Small context',
+      baseUrl: 'https://model.example/v1',
+      modelName: 'small-model',
+      protocol: 'openai-responses' as const,
+      authentication: 'api-key' as const,
+      supportsImageInput: false,
+      contextWindowTokens: 10_000,
+      imageGenerationQuality: 'auto' as const,
+      apiKey: { action: 'keep' as const }
+    }
+
+    expect(() =>
+      runtimeSettingsInputSchema.parse(
+        settings({
+          modelProfiles: [profile],
+          defaultModelProfileId: profileId
+        })
+      )
+    ).toThrow()
+
+    await store.update(
+      settings({
+        modelProfiles: [
+          {
+            ...profile,
+            contextWindowTokens: 32_000
+          }
+        ],
+        defaultModelProfileId: profileId
+      })
+    )
+    const persisted = JSON.parse(
+      await readFile(filePath, 'utf8')
+    ) as {
+      modelProfiles: Array<{ contextWindowTokens?: number }>
+    }
+    persisted.modelProfiles[0]!.contextWindowTokens = 10_000
+    await writeFile(filePath, JSON.stringify(persisted), 'utf8')
+
+    const migrated = new RuntimeSettingsStore(filePath, cipher, {})
+    await expect(migrated.getPublicSettings()).resolves.toMatchObject({
+      modelProfiles: [
+        expect.objectContaining({
+          id: profileId,
+          contextWindowTokens: undefined
+        })
+      ]
+    })
+  })
+
   it('configures bundled runtimes from the default model profile', async () => {
     const { store } = await createStore()
 

src/main/runtime-settings-store.ts

@@ -14,6 +14,7 @@ import {
   imageGenerationQualitySchema,
   isAgentRuntimeModelProtocol,
   isDeepSeekHarnessModelProfile,
+  minimumModelContextWindowTokens,
   modelAuthenticationSchema,
   modelProtocolSchema,
   runtimeModelSourceSchema,
@@ -555,7 +556,12 @@ function migrateVersion10(
 function normalizeStoredSettings(settings: StoredSettings): StoredSettings {
   const modelProfiles = settings.modelProfiles.map((profile) => ({
     ...profile,
-    baseUrl: normalizeModelBaseUrl(profile.baseUrl)
+    baseUrl: normalizeModelBaseUrl(profile.baseUrl),
+    contextWindowTokens:
+      profile.contextWindowTokens === undefined ||
+      profile.contextWindowTokens >= minimumModelContextWindowTokens
+        ? profile.contextWindowTokens
+        : undefined
   }))
   const fallbackProfileId = compatibleTextProfileId({
     modelProfiles,

src/renderer/src/App.test.tsx

@@ -902,6 +902,32 @@ describe('App', () => {
     }
   })
 
+  it('keeps a recently visited workspace page mounted', async () => {
+    render(<App />)
+    fireEvent.click(
+      await screen.findByRole('button', { name: '知识库' })
+    )
+    const heading = await screen.findByRole('heading', {
+      level: 1,
+      name: '知识库'
+    })
+    const route = heading.closest<HTMLElement>('[data-route="knowledge"]')
+    expect(route).not.toHaveAttribute('hidden')
+
+    fireEvent.click(screen.getByRole('button', { name: '对话' }))
+    expect(heading).toBeInTheDocument()
+    expect(route).toHaveAttribute('hidden')
+
+    fireEvent.click(screen.getByRole('button', { name: '知识库' }))
+    expect(
+      await screen.findByRole('heading', {
+        level: 1,
+        name: '知识库'
+      })
+    ).toBe(heading)
+    expect(route).not.toHaveAttribute('hidden')
+  })
+
   it('preserves title, message, and project filtering with deferred search', async () => {
     vi.mocked(api.conversations.list).mockResolvedValueOnce([
       {
@@ -1585,7 +1611,8 @@ describe('App', () => {
     fireEvent.scroll(chat)
 
     fireEvent.click(screen.getByRole('button', { name: '知识库' }))
-    expect(container.querySelector('.chat')).not.toBeInTheDocument()
+    expect(chat).toBeInTheDocument()
+    expect(chat.closest('[data-route="chat"]')).toHaveAttribute('hidden')
     act(() => {
       agentListener?.({
         requestId: request.requestId,
@@ -1597,7 +1624,7 @@ describe('App', () => {
     fireEvent.click(screen.getByRole('button', { name: '对话' }))
     expect(await screen.findByText('后台新增的回复内容')).toBeInTheDocument()
     const restoredChat = container.querySelector<HTMLElement>('.chat')
-    expect(restoredChat).not.toBe(chat)
+    expect(restoredChat).toBe(chat)
     expect(restoredChat?.scrollTop).toBe(175)
     expect(
       screen.getByRole('button', { name: '到底部' })
@@ -1609,6 +1636,16 @@ describe('App', () => {
       '00000000-0000-4000-8000-000000000461'
     const secondConversationId =
       '00000000-0000-4000-8000-000000000462'
+    const draftAttachment = {
+      id: '00000000-0000-4000-8000-000000000463',
+      name: '第一段草稿附件.md',
+      size: 1_024,
+      preview: '会话级草稿附件',
+      kind: 'text' as const
+    }
+    vi.mocked(api.context.selectFiles).mockResolvedValueOnce([
+      draftAttachment
+    ])
     vi.mocked(api.conversations.list).mockResolvedValueOnce([
       {
         id: firstConversationId,
@@ -1619,6 +1656,7 @@ describe('App', () => {
           id: `00000000-0000-4000-8100-${String(index).padStart(12, '0')}`,
           role: index % 2 === 0 ? ('user' as const) : ('assistant' as const),
           content: `第一段历史 ${String(index).padStart(3, '0')}`,
+          reasoning: index === 159 ? '需要保留展开状态' : undefined,
           createdAt: 1_775_000_000_000 + index,
           state: 'complete' as const
         }))
@@ -1647,31 +1685,65 @@ describe('App', () => {
         name: '加载更早的消息（还剩 81 条）'
       })
     )
-    expect(container.querySelectorAll('.message')).toHaveLength(160)
+    const firstPane = container.querySelector<HTMLElement>(
-    const firstChat = container.querySelector<HTMLElement>('.chat')
+      `[data-conversation-id="${firstConversationId}"]`
+    )
+    expect(firstPane?.querySelectorAll('.message')).toHaveLength(160)
+    const firstChat = firstPane?.querySelector<HTMLElement>('.chat')
     if (!firstChat) {
       throw new Error('Missing first chat scroll container')
     }
+    const reasoningDetails = firstPane?.querySelector<HTMLDetailsElement>(
+      '.message-reasoning'
+    )
+    if (!reasoningDetails) {
+      throw new Error('Missing reasoning details')
+    }
+    reasoningDetails.open = true
     Object.defineProperties(firstChat, {
       clientHeight: { configurable: true, value: 400 },
       scrollHeight: { configurable: true, value: 1_600 },
       scrollTop: { configurable: true, writable: true, value: 225 }
     })
     fireEvent.scroll(firstChat)
+    fireEvent.change(screen.getByLabelText('向 GoodBuddy 提问'), {
+      target: { value: '第一段会话草稿' }
+    })
+    fireEvent.click(screen.getByLabelText('添加附件'))
+    expect(
+      await screen.findByText(draftAttachment.name)
+    ).toBeInTheDocument()
 
     fireEvent.click(
       screen.getByText('第二段会话').closest('button')!
     )
     expect(await screen.findByText('第二段会话内容')).toBeInTheDocument()
+    expect(screen.getByLabelText('向 GoodBuddy 提问')).toHaveValue('')
+    expect(
+      screen.queryByText(draftAttachment.name)
+    ).not.toBeInTheDocument()
+    fireEvent.change(screen.getByLabelText('向 GoodBuddy 提问'), {
+      target: { value: '第二段会话草稿' }
+    })
     fireEvent.click(
       screen.getByText('第一段长会话').closest('button')!
     )
 
     expect(await screen.findByText('第一段历史 001')).toBeInTheDocument()
-    expect(container.querySelectorAll('.message')).toHaveLength(160)
+    const restoredFirstPane = container.querySelector<HTMLElement>(
-    expect(container.querySelector<HTMLElement>('.chat')?.scrollTop).toBe(
+      `[data-conversation-id="${firstConversationId}"]`
-      225
     )
+    expect(restoredFirstPane).toBe(firstPane)
+    expect(restoredFirstPane?.querySelectorAll('.message')).toHaveLength(
+      160
+    )
+    expect(restoredFirstPane?.querySelector('.chat')).toBe(firstChat)
+    expect(firstChat.scrollTop).toBe(225)
+    expect(reasoningDetails).toHaveAttribute('open')
+    expect(screen.getByLabelText('向 GoodBuddy 提问')).toHaveValue(
+      '第一段会话草稿'
+    )
+    expect(screen.getByText(draftAttachment.name)).toBeInTheDocument()
   })
 
   it('requires an accessible confirmation before permanently deleting a conversation', async () => {
@@ -2227,6 +2299,124 @@ describe('App', () => {
     expect(screen.getByText('正在分析真实推理内容')).toBeVisible()
   })
 
+  it('shows live context usage and keeps explicit compression status', async () => {
+    const settings = await api.settings.getRuntime()
+    vi.mocked(api.settings.getRuntime).mockResolvedValueOnce({
+      ...settings,
+      provider: 'model',
+      modelProfiles: settings.modelProfiles.map((profile) => ({
+        ...profile,
+        contextWindowTokens: 32_000
+      })),
+      contextCompression: {
+        enabled: true,
+        triggerTokens: 200_000,
+        recentRawTokens: 32_000,
+        modelSource: { kind: 'current' },
+        summaryPrompt: 'Preserve important facts.'
+      }
+    })
+    render(<App />)
+
+    expect(
+      await screen.findByText(/上下文 ≈.+ \/ 32\.0K · \d+%/u)
+    ).toBeInTheDocument()
+    expect(
+      screen.getByRole('progressbar', {
+        name: '当前上下文使用量'
+      })
+    ).toBeInTheDocument()
+    expect(
+      screen.queryByText('只读问答，不修改文件')
+    ).not.toBeInTheDocument()
+    expect(
+      await screen.findByText('快捷唤起：', { exact: false })
+    ).toHaveTextContent('快捷唤起：Ctrl+Shift+Space')
+
+    fireEvent.change(screen.getByLabelText('向 GoodBuddy 提问'), {
+      target: { value: '中'.repeat(1_000) }
+    })
+    expect(
+      screen.getByText(/上下文 ≈5\.\dK \/ 32\.0K/u)
+    ).toBeInTheDocument()
+    fireEvent.click(screen.getByLabelText('发送'))
+    await waitFor(() => expect(run).toHaveBeenCalledOnce())
+    const request = run.mock.calls[0]?.[0]
+    if (!request) {
+      throw new Error('Missing request')
+    }
+
+    act(() => {
+      agentListener?.({
+        requestId: request.requestId,
+        type: 'context-compression',
+        state: 'started',
+        estimatedBeforeTokens: 22_000,
+        effectiveTriggerTokens: 20_000,
+        contextWindowTokens: 32_000,
+        recentRawTokens: 32_000,
+        coveredMessageCount: 2
+      })
+    })
+    expect(
+      screen.getByText('正在压缩较早对话…')
+    ).toBeInTheDocument()
+
+    act(() => {
+      agentListener?.({
+        requestId: request.requestId,
+        type: 'status',
+        message: 'sonnet-5 正在思考'
+      })
+    })
+    expect(
+      screen.getByText('正在压缩较早对话…')
+    ).toBeInTheDocument()
+    expect(screen.getByText('sonnet-5 正在思考')).toBeInTheDocument()
+
+    act(() => {
+      agentListener?.({
+        requestId: request.requestId,
+        type: 'context-compression',
+        state: 'completed',
+        estimatedBeforeTokens: 22_000,
+        estimatedAfterTokens: 9_000,
+        effectiveTriggerTokens: 20_000,
+        contextWindowTokens: 32_000,
+        recentRawTokens: 32_000,
+        coveredMessageCount: 2,
+        summaryTokens: 1_000
+      })
+      agentListener?.({
+        requestId: request.requestId,
+        type: 'context-metrics',
+        estimatedInputTokens: 9_000,
+        effectiveTriggerTokens: 20_000,
+        contextWindowTokens: 32_000,
+        compressionEnabled: true,
+        recentRawTokens: 32_000,
+        coveredMessageCount: 2,
+        summaryTokens: 1_000
+      })
+    })
+
+    expect(
+      screen.getByText('已压缩较早对话 · ≈22.0K → ≈9.0K')
+    ).toBeInTheDocument()
+    expect(
+      screen.getByText('上下文 ≈9.0K / 32.0K · 28%')
+    ).toBeInTheDocument()
+    act(() => {
+      agentListener?.({
+        requestId: request.requestId,
+        type: 'done'
+      })
+    })
+    expect(
+      screen.getByText('已压缩较早对话 · ≈22.0K → ≈9.0K')
+    ).toBeInTheDocument()
+  })
+
   it('keeps a tool failure in details and hides retry after continuing', async () => {
     render(<App />)
 
@@ -2871,9 +3061,7 @@ describe('App', () => {
     expect(
       screen.queryByRole('heading', { name: '设置中心' })
     ).not.toBeInTheDocument()
-    expect(
+    expect(screen.getByLabelText('发送')).toBeDisabled()
-      await screen.findByText(/请先配置可用的模型或 Agent Runtime/u)
-    ).toBeInTheDocument()
     expect(run).not.toHaveBeenCalled()
   })
 
@@ -3794,9 +3982,7 @@ describe('App', () => {
     expect(mode).toBeEnabled()
     expect(mode.closest('.composer')).not.toBeNull()
     expect(
-      await screen.findByText(
+      await screen.findByText('快捷唤起：', { exact: false })
-        new RegExp(`${label} Ask 模式.*只允许搜索当前启用的知识库`)
-      )
     ).toBeInTheDocument()
     selectComposerOption('工作模式', 'Execute · 受控执行')
     expect(mode).toHaveAccessibleName(
@@ -4076,7 +4262,11 @@ describe('App', () => {
       expect(notification).toHaveTextContent(
         '当前对话已切换到 OpenCode · 默认模型'
       )
-      expect(screen.getByText(/Ask 模式：只读问答/)).toBeInTheDocument()
+      expect(
+        screen.getByRole('button', {
+          name: '工作模式：Ask · 只读问答'
+        })
+      ).toBeInTheDocument()
 
       fireEvent.click(
         screen.getByRole('button', {
@@ -4102,7 +4292,11 @@ describe('App', () => {
           '当前对话已切换到 Continue · 默认模型'
         )
       ).not.toBeInTheDocument()
-      expect(screen.getByText(/Ask 模式：只读问答/)).toBeInTheDocument()
+      expect(
+        screen.getByRole('button', {
+          name: '工作模式：Ask · 只读问答'
+        })
+      ).toBeInTheDocument()
     } finally {
       vi.useRealTimers()
     }

src/renderer/src/ChatTimeline.test.tsx

@@ -1,4 +1,4 @@
-import { cleanup, render } from '@testing-library/react'
+import { cleanup, render, screen } from '@testing-library/react'
 import { afterEach, describe, expect, it, vi } from 'vitest'
 import {
   ChatTimeline,
@@ -85,4 +85,54 @@ describe('ChatTimeline', () => {
     )
     expect(unchangedDetails).toHaveAttribute('open')
   })
+
+  it('places compression progress between the user and assistant messages', () => {
+    const messages: Message[] = [
+      {
+        id: 'user-message',
+        role: 'user',
+        content: 'Continue',
+        createdAt: 1_775_000_000_000,
+        state: 'complete'
+      },
+      {
+        id: 'assistant-message',
+        role: 'assistant',
+        content: 'Answer',
+        contextCompression: {
+          state: 'completed',
+          estimatedBeforeTokens: 22_000,
+          estimatedAfterTokens: 9_000
+        },
+        createdAt: 1_775_000_001_000,
+        state: 'complete'
+      }
+    ]
+    const { container } = render(
+      <ChatTimeline
+        artifactById={new Map()}
+        conversationId="conversation-1"
+        hiddenMessageCount={0}
+        isUnusedConversation={false}
+        locale="zh-CN"
+        messageStartIndex={0}
+        messages={messages}
+        {...callbacks}
+        retryContent=""
+        totalMessageCount={messages.length}
+      />
+    )
+
+    const children = Array.from(
+      container.querySelector('.message-list')?.children ?? []
+    )
+    expect(children.map((element) => element.className)).toEqual([
+      'message message--user',
+      'context-compression-event context-compression-event--completed',
+      'message message--assistant'
+    ])
+    expect(
+      screen.getByRole('status')
+    ).toHaveTextContent('已压缩较早对话 · ≈22.0K → ≈9.0K')
+  })
 })

src/renderer/src/ChatTimeline.tsx

@@ -51,6 +51,11 @@ export type Message = {
   createdAt: number
   state: 'streaming' | 'complete' | 'error'
   status?: string
+  contextCompression?: {
+    state: 'compressing' | 'completed' | 'failed'
+    estimatedBeforeTokens: number
+    estimatedAfterTokens?: number
+  }
   tools?: ToolActivity[]
   subagents?: SubagentActivity[]
   approval?: {
@@ -74,6 +79,14 @@ export type ImageViewerItem = {
   title: string
 }
 
+function formatCompactTokens(tokens: number): string {
+  if (tokens < 1_000) {
+    return tokens.toLocaleString()
+  }
+  const value = tokens / 1_000
+  return `${value >= 100 ? Math.round(value) : value.toFixed(1)}K`
+}
+
 type MessageBlockRenderItem =
   | {
       kind: 'block'
@@ -270,6 +283,41 @@ function ChatMessageRowView({
   const { t } = useTranslation('app')
 
   return (
+    <>
+      {message.role === 'assistant' && message.contextCompression && (
+        <div
+          aria-live="polite"
+          className={`context-compression-event context-compression-event--${message.contextCompression.state}`}
+          role="status"
+        >
+          <span className="context-compression-event__line" />
+          <span className="context-compression-event__label">
+            <span
+              aria-hidden="true"
+              className={
+                message.contextCompression.state === 'compressing'
+                  ? 'message__status-dot message__status-dot--active'
+                  : 'message__status-dot'
+              }
+            />
+            {message.contextCompression.state === 'compressing'
+              ? t('chat.contextCompression.compressing')
+              : message.contextCompression.state === 'completed' &&
+                  message.contextCompression.estimatedAfterTokens !==
+                    undefined
+                ? t('chat.contextCompression.completed', {
+                    before: formatCompactTokens(
+                      message.contextCompression.estimatedBeforeTokens
+                    ),
+                    after: formatCompactTokens(
+                      message.contextCompression.estimatedAfterTokens
+                    )
+                  })
+                : t('chat.contextCompression.failed')}
+          </span>
+          <span className="context-compression-event__line" />
+        </div>
+      )}
     <article
       className={`message message--${message.role}`}
       ref={(element) => onArticleRef(message.id, element)}
@@ -755,6 +803,7 @@ function ChatMessageRowView({
         )}
       </div>
     </article>
+    </>
   )
 }
 

src/renderer/src/SettingsPanel.test.tsx

@@ -604,6 +604,7 @@ describe('SettingsPanel runtime files', () => {
       '上下文上限（可选）'
     )
     expect(contextWindow).toHaveValue(null)
+    expect(contextWindow).toHaveAttribute('min', '32')
     fireEvent.change(contextWindow, { target: { value: '256' } })
     fireEvent.click(screen.getByRole('button', { name: '保存设置' }))
 

src/renderer/src/SettingsPanel.tsx

@@ -2418,7 +2418,7 @@ export function SettingsPanel({
                           aria-label={t('model.profile.contextWindow')}
                           inputMode="numeric"
                           max={10_000}
-                          min={8}
+                          min={32}
                           onChange={(event) => {
                             const value = event.target.valueAsNumber
                             updateModelProfile(profile.id, {

src/renderer/src/i18n/locales/en-US/app.ts

@@ -187,6 +187,12 @@ export const app = {
       streaming: 'Reasoning',
       complete: 'Reasoning process'
     },
+    contextCompression: {
+      compressing: 'Compressing earlier conversation…',
+      completed:
+        'Earlier conversation compressed · ≈{{before}} → ≈{{after}}',
+      failed: 'Earlier conversation compression failed'
+    },
     sources: 'Sources: {{sources}}',
     citations: {
       view: 'View {{count}} evidence references',
@@ -314,6 +320,14 @@ export const app = {
     send: 'Send',
     sendTitle: 'Send message',
     shortcut: 'Quick access: ',
+    context: {
+      tokenCount: 'Context ≈{{used}}',
+      windowUsage: 'Context ≈{{used}} / {{total}} · {{percentage}}%',
+      thresholdUsage:
+        'Compression threshold ≈{{used}} / {{total}} · {{percentage}}%',
+      progressLabel: 'Current context usage',
+      compressionTrigger: 'Automatic compression at ≈{{tokens}}'
+    },
     experts: {
       general: 'General assistant',
       generalDescription: 'Default single assistant',

src/renderer/src/i18n/locales/en-US/settings.ts

@@ -495,7 +495,7 @@ export const settings = {
         'When enabled, GoodBuddy can send image context to this model connection.',
       contextWindow: 'Context window (optional)',
       contextWindowDescription:
-        'Enter K tokens. Leave blank when unknown. This value is used only for GoodBuddy local budget calculations.',
+        'Enter 32K–10000K tokens. Leave blank when unknown. This value is used only for GoodBuddy local budget calculations.',
       imageQuality: 'Image quality',
       imageQualityAriaLabel: 'Image quality for {{name}}',
       quality: {

src/renderer/src/i18n/locales/zh-CN/app.ts

@@ -182,6 +182,11 @@ export const app = {
       streaming: '正在推理',
       complete: '推理过程'
     },
+    contextCompression: {
+      compressing: '正在压缩较早对话…',
+      completed: '已压缩较早对话 · ≈{{before}} → ≈{{after}}',
+      failed: '较早对话压缩失败'
+    },
     sources: '来源：{{sources}}',
     citations: {
       view: '查看 {{count}} 条证据引用',
@@ -306,6 +311,14 @@ export const app = {
     send: '发送',
     sendTitle: '发送消息',
     shortcut: '快捷唤起：',
+    context: {
+      tokenCount: '上下文 ≈{{used}}',
+      windowUsage: '上下文 ≈{{used}} / {{total}} · {{percentage}}%',
+      thresholdUsage:
+        '距压缩阈值 ≈{{used}} / {{total}} · {{percentage}}%',
+      progressLabel: '当前上下文使用量',
+      compressionTrigger: '自动压缩线：≈{{tokens}}'
+    },
     experts: {
       general: '通用助手',
       generalDescription: '默认单助手',

src/renderer/src/i18n/locales/zh-CN/settings.ts

@@ -452,7 +452,7 @@ export const settings = {
         '启用后，GoodBuddy 可将图片上下文发送给此模型连接。',
       contextWindow: '上下文上限（可选）',
       contextWindowDescription:
-        '以 K tokens 填写。留空表示未知；此值仅用于 GoodBuddy 本地预算计算。',
+        '以 K tokens 填写，范围为 32K–10000K。留空表示未知；此值仅用于 GoodBuddy 本地预算计算。',
       imageQuality: '图片质量',
       imageQualityAriaLabel: '图片质量 {{name}}',
       quality: {

src/renderer/src/keep-alive-cache.test.ts

@@ -0,0 +1,96 @@
+import { describe, expect, it } from 'vitest'
+import {
+  pruneKeepAliveEntries,
+  touchKeepAliveEntry
+} from './keep-alive-cache'
+
+describe('keep-alive cache', () => {
+  it('updates a visited entry without duplicating it', () => {
+    expect(
+      touchKeepAliveEntry(
+        [
+          { key: 'chat', lastVisitedAt: 10 },
+          { key: 'knowledge', lastVisitedAt: 20 }
+        ],
+        'chat',
+        30
+      )
+    ).toEqual([
+      { key: 'knowledge', lastVisitedAt: 20 },
+      { key: 'chat', lastVisitedAt: 30 }
+    ])
+  })
+
+  it('keeps recent and protected entries while expiring inactive ones', () => {
+    expect(
+      pruneKeepAliveEntries(
+        [
+          { key: 'one', lastVisitedAt: 10 },
+          { key: 'two', lastVisitedAt: 20 },
+          { key: 'three', lastVisitedAt: 30 },
+          { key: 'four', lastVisitedAt: 40 }
+        ],
+        {
+          currentKey: 'four',
+          expiresAfterMs: 50,
+          maximumEntries: 4,
+          now: 100,
+          protectedKeys: new Set(['one']),
+          recentEntries: 2
+        }
+      )
+    ).toEqual([
+      { key: 'four', lastVisitedAt: 40 },
+      { key: 'three', lastVisitedAt: 30 },
+      { key: 'one', lastVisitedAt: 10 }
+    ])
+  })
+
+  it('enforces the hard limit with least-recently-used eviction', () => {
+    expect(
+      pruneKeepAliveEntries(
+        Array.from({ length: 8 }, (_, index) => ({
+          key: `conversation-${index}`,
+          lastVisitedAt: index
+        })),
+        {
+          currentKey: 'conversation-7',
+          expiresAfterMs: 1_000,
+          maximumEntries: 5,
+          now: 10,
+          protectedKeys: new Set(['conversation-0']),
+          recentEntries: 2
+        }
+      ).map((entry) => entry.key)
+    ).toEqual([
+      'conversation-7',
+      'conversation-6',
+      'conversation-5',
+      'conversation-4',
+      'conversation-0'
+    ])
+  })
+
+  it('expires an unprotected entry after one hour', () => {
+    const entries = [{ key: 'knowledge', lastVisitedAt: 1_000 }]
+    const options = {
+      expiresAfterMs: 60 * 60 * 1_000,
+      maximumEntries: 4,
+      protectedKeys: new Set<string>(),
+      recentEntries: 0
+    }
+
+    expect(
+      pruneKeepAliveEntries(entries, {
+        ...options,
+        now: 1_000 + 60 * 60 * 1_000 - 1
+      })
+    ).toEqual(entries)
+    expect(
+      pruneKeepAliveEntries(entries, {
+        ...options,
+        now: 1_000 + 60 * 60 * 1_000
+      })
+    ).toEqual([])
+  })
+})

src/renderer/src/keep-alive-cache.ts

@@ -0,0 +1,69 @@
+export type KeepAliveCacheEntry<Key extends string> = {
+  key: Key
+  lastVisitedAt: number
+}
+
+export function touchKeepAliveEntry<Key extends string>(
+  entries: readonly KeepAliveCacheEntry<Key>[],
+  key: Key,
+  visitedAt: number
+): KeepAliveCacheEntry<Key>[] {
+  const existing = entries.find((entry) => entry.key === key)
+  if (existing?.lastVisitedAt === visitedAt) {
+    return [...entries]
+  }
+  return [
+    ...entries.filter((entry) => entry.key !== key),
+    { key, lastVisitedAt: visitedAt }
+  ]
+}
+
+export function pruneKeepAliveEntries<Key extends string>(
+  entries: readonly KeepAliveCacheEntry<Key>[],
+  {
+    currentKey,
+    expiresAfterMs,
+    maximumEntries,
+    now,
+    protectedKeys,
+    recentEntries
+  }: {
+    currentKey?: Key
+    expiresAfterMs: number
+    maximumEntries: number
+    now: number
+    protectedKeys?: ReadonlySet<Key>
+    recentEntries: number
+  }
+): KeepAliveCacheEntry<Key>[] {
+  const newestFirst = [...entries].sort(
+    (left, right) => right.lastVisitedAt - left.lastVisitedAt
+  )
+  const alwaysKeep = new Set(
+    newestFirst.slice(0, recentEntries).map((entry) => entry.key)
+  )
+  if (currentKey) {
+    alwaysKeep.add(currentKey)
+  }
+  protectedKeys?.forEach((key) => alwaysKeep.add(key))
+
+  const retained = newestFirst.filter(
+    (entry) =>
+      alwaysKeep.has(entry.key) ||
+      now - entry.lastVisitedAt < expiresAfterMs
+  )
+  if (retained.length <= maximumEntries) {
+    return retained
+  }
+
+  const removableOldestFirst = retained
+    .filter((entry) => !alwaysKeep.has(entry.key))
+    .sort((left, right) => left.lastVisitedAt - right.lastVisitedAt)
+  const removeCount = retained.length - maximumEntries
+  const removedKeys = new Set(
+    removableOldestFirst
+      .slice(0, removeCount)
+      .map((entry) => entry.key)
+  )
+  return retained.filter((entry) => !removedKeys.has(entry.key))
+}

src/renderer/src/styles.css

@@ -1963,6 +1963,17 @@ textarea:focus-visible {
   grid-template-rows: 58px minmax(0, 1fr) auto;
 }
 
+.workspace-route-cache {
+  display: grid;
+  min-width: 0;
+  min-height: 0;
+  overflow: hidden;
+}
+
+.workspace-route-cache[hidden] {
+  display: none;
+}
+
 .topbar {
   display: flex;
   min-width: 0;
@@ -2975,6 +2986,15 @@ button > svg {
   background: var(--surface-raised);
 }
 
+.chat-history-pane {
+  height: 100%;
+  min-height: 0;
+}
+
+.chat-history-pane[hidden] {
+  display: none;
+}
+
 .chat {
   height: 100%;
   min-height: 0;
@@ -3608,6 +3628,55 @@ button > svg {
   color: var(--danger);
 }
 
+.context-compression-event {
+  display: flex;
+  width: 100%;
+  align-items: center;
+  color: var(--text-muted);
+  gap: var(--space-2);
+}
+
+.context-compression-event__line {
+  height: 1px;
+  min-width: var(--space-6);
+  flex: 1;
+  background: var(--border-subtle);
+}
+
+.context-compression-event__label {
+  display: inline-flex;
+  align-items: center;
+  padding: var(--space-1) var(--space-2);
+  border: 1px solid var(--border-default);
+  border-radius: var(--radius-control);
+  background: var(--surface-subtle);
+  color: var(--text-secondary);
+  font-size: var(--font-caption);
+  gap: var(--space-2);
+  white-space: nowrap;
+}
+
+.context-compression-event--compressing
+  .context-compression-event__label {
+  border-color: var(--accent-selected);
+  background: var(--accent-subtle);
+  color: var(--accent);
+}
+
+.context-compression-event--completed
+  .context-compression-event__label {
+  border-color: color-mix(in srgb, var(--success) 35%, var(--border-default));
+  background: var(--success-subtle);
+  color: var(--success);
+}
+
+.context-compression-event--failed
+  .context-compression-event__label {
+  border-color: var(--danger-border);
+  background: var(--danger-subtle);
+  color: var(--danger);
+}
+
 .message__status-dot {
   flex: 0 0 auto;
   width: 6px;
@@ -4409,7 +4478,7 @@ button > svg {
 }
 
 .composer-picker--mode > .model-button {
-  width: 96px;
+  width: 108px;
 }
 
 .composer-picker--ask svg {
@@ -4595,29 +4664,31 @@ button > svg {
   background: var(--danger-solid);
 }
 
-.composer-hint {
+.composer-meta {
   display: flex;
   margin: var(--space-2) 0 0;
   align-items: center;
-  justify-content: center;
+  justify-content: flex-end;
-  color: var(--text-secondary);
   font-size: var(--font-caption);
   flex-wrap: wrap;
-  gap: var(--space-1) var(--space-3);
+  gap: var(--space-2) var(--space-3);
   line-height: 1.45;
-  text-align: center;
 }
 
-.composer-hint--error {
+.composer-meta__error {
+  margin-right: auto;
+}
+
+.composer-meta__error {
   color: var(--danger);
 }
 
-.composer-hint__shortcut {
+.composer-meta__shortcut {
   color: var(--text-muted);
   white-space: nowrap;
 }
 
-.composer-hint kbd {
+.composer-meta kbd {
   padding: 1px var(--space-1);
   border: 1px solid var(--border-default);
   border-radius: 4px;
@@ -4627,6 +4698,52 @@ button > svg {
   font-size: 10px;
 }
 
+.composer-context-meter {
+  display: flex;
+  min-width: 0;
+  align-items: center;
+  margin-right: auto;
+  color: var(--text-muted);
+  gap: var(--space-2);
+}
+
+.composer-context-meter--warning {
+  color: var(--warning);
+}
+
+.composer-context-meter__summary {
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
+.composer-context-meter__track {
+  position: relative;
+  width: 112px;
+  height: 4px;
+  flex: 0 0 112px;
+  border-radius: 999px;
+  overflow: visible;
+  background: var(--surface-muted);
+}
+
+.composer-context-meter__fill {
+  position: absolute;
+  border-radius: inherit;
+  background: currentColor;
+  inset: 0 auto 0 0;
+  transition: width var(--motion-fast) ease-out;
+}
+
+.composer-context-meter__trigger {
+  position: absolute;
+  top: -2px;
+  width: 1px;
+  height: 8px;
+  background: var(--text-secondary);
+  transform: translateX(-50%);
+}
+
 @container (max-width: 700px) {
   .composer__controls {
     flex-wrap: wrap;
@@ -4649,6 +4766,15 @@ button > svg {
   .model-button {
     width: 100%;
   }
+
+  .composer-context-meter {
+    width: 100%;
+  }
+
+  .composer-context-meter__track {
+    min-width: 64px;
+    flex: 1;
+  }
 }
 
 .settings-backdrop {

src/shared/assistant-contracts.ts

@@ -147,6 +147,14 @@ export const conversationMessageSchema = z
     createdAt: z.number().int().nonnegative(),
     state: z.enum(['streaming', 'complete', 'error']),
     status: z.string().max(4_000).optional(),
+    contextCompression: z
+      .object({
+        state: z.enum(['compressing', 'completed', 'failed']),
+        estimatedBeforeTokens: z.number().int().nonnegative(),
+        estimatedAfterTokens: z.number().int().nonnegative().optional()
+      })
+      .strict()
+      .optional(),
     tools: z.array(conversationToolActivitySchema).max(100).optional(),
     sources: z.array(z.string().max(8_192)).max(100).optional(),
     sourceReferences: z

src/shared/context-window.ts

@@ -0,0 +1,63 @@
+export const minimumModelContextWindowTokens = 32_000
+export const maximumModelContextWindowTokens = 10_000_000
+export const contextOutputAndSafetyTokens = 12_000
+export const estimatedContextRequestOverheadTokens = 4_000
+
+export type ContextWindowMessage = {
+  role: 'user' | 'assistant'
+  content: string
+}
+
+export function estimateTextTokens(value: string): number {
+  let asciiCharacters = 0
+  let nonAsciiCharacters = 0
+  for (const character of value) {
+    if (character.codePointAt(0)! <= 0x7f) {
+      asciiCharacters += 1
+    } else {
+      nonAsciiCharacters += 1
+    }
+  }
+  return Math.max(
+    1,
+    Math.ceil(asciiCharacters / 4 + nonAsciiCharacters)
+  )
+}
+
+export function estimateMessagesTokens(
+  messages: readonly ContextWindowMessage[]
+): number {
+  return messages.reduce(
+    (total, message) => total + estimateTextTokens(message.content) + 4,
+    0
+  )
+}
+
+export function estimateContextInputTokens(input: {
+  history: readonly ContextWindowMessage[]
+  prompt: string
+  summaryTokens?: number
+}): number {
+  return (
+    estimateMessagesTokens(input.history) +
+    estimateTextTokens(input.prompt) +
+    (input.summaryTokens ?? 0) +
+    estimatedContextRequestOverheadTokens
+  )
+}
+
+export function getEffectiveContextTriggerTokens(input: {
+  triggerTokens: number
+  contextWindowTokens?: number
+}): number {
+  if (input.contextWindowTokens === undefined) {
+    return input.triggerTokens
+  }
+  return Math.min(
+    input.triggerTokens,
+    Math.max(
+      input.contextWindowTokens,
+      minimumModelContextWindowTokens
+    ) - contextOutputAndSafetyTokens
+  )
+}

src/shared/contracts.ts

@@ -1,4 +1,8 @@
 import { z } from 'zod'
+import {
+  maximumModelContextWindowTokens,
+  minimumModelContextWindowTokens
+} from './context-window'
 import type {
   BrowserProfileCreateInput,
   BrowserProfileRenameInput,
@@ -416,6 +420,11 @@ const modelApiKeyUpdateSchema = z.discriminatedUnion('action', [
   z.object({ action: z.literal('clear') }).strict()
 ])
 
+export {
+  maximumModelContextWindowTokens,
+  minimumModelContextWindowTokens
+} from './context-window'
+
 const modelProfileInputSchema = z
   .object({
     id: modelProfileIdSchema,
@@ -433,8 +442,8 @@ const modelProfileInputSchema = z
     contextWindowTokens: z
       .number()
       .int()
-      .min(8_000)
+      .min(minimumModelContextWindowTokens)
-      .max(10_000_000)
+      .max(maximumModelContextWindowTokens)
       .optional(),
     imageGenerationQuality: imageGenerationQualitySchema,
     apiKey: modelApiKeyUpdateSchema
@@ -907,6 +916,29 @@ export type AgentEvent =
       type: 'reasoning'
       delta: string
     }
+  | {
+      requestId: string
+      type: 'context-metrics'
+      estimatedInputTokens: number
+      effectiveTriggerTokens: number
+      contextWindowTokens?: number
+      compressionEnabled: boolean
+      recentRawTokens: number
+      coveredMessageCount: number
+      summaryTokens: number
+    }
+  | {
+      requestId: string
+      type: 'context-compression'
+      state: 'started' | 'completed'
+      estimatedBeforeTokens: number
+      estimatedAfterTokens?: number
+      effectiveTriggerTokens: number
+      contextWindowTokens?: number
+      recentRawTokens: number
+      coveredMessageCount: number
+      summaryTokens?: number
+    }
   | {
       requestId: string
       type: 'tool'