feat(composer): replicate WorkBuddy branch label and context usage (TODO 21)

src/main/agent/loop.ts

@@ -97,6 +97,8 @@ export async function runTurn(options: RunTurnOptions): Promise<TurnResult> {
         } else if (delta.type === 'reasoning') {
           reasoning += delta.text
           emit({ runId, type: 'part', part: { type: 'reasoning', id: `reasoning-${round}`, text: reasoning } })
+        } else if (delta.type === 'usage') {
+          emit({ runId, type: 'usage', usage: delta.usage })
         } else if (delta.type === 'tool_calls') {
           for (const call of delta.calls) {
             pendingCalls.push({ id: call.id, name: call.function.name, argsRaw: call.function.arguments })

src/main/agent/omp-turn.ts

@@ -11,7 +11,7 @@
  * - 取消（abort）→ ChatEvent `cancelled`
  */
 
-import type { ChatEvent, ToolCallRecord } from '@shared/types'
+import type { ChatEvent, TokenUsage, ToolCallRecord } from '@shared/types'
 import { OmpKernel, type OmpFrame, type OmpToolInfo } from '../omp'
 import { toolSpecs } from './tools'
 import { executeTurnTool } from './conversation-tools'
@@ -169,6 +169,11 @@ export async function runOmpTurn(options: RunOmpTurnOptions): Promise<OmpTurnRes
           if (isRecord(message) && message.role === 'assistant' && message.stopReason === 'error') {
             failProvider(message.errorMessage)
           }
+          // 真实上下文用量：OMP 把上游 usage 记在助手消息上（内核源码里的判定是
+          // `contextTokens ?? input + cacheRead + cacheWrite`，即本次请求真实消耗的上下文）。
+          // 拿不到就不发事件，绝不估算。
+          const usage = readOmpUsage(message)
+          if (usage) emit({ runId, type: 'usage', usage })
           break
         }
 
@@ -452,6 +457,31 @@ function isRecord(value: unknown): value is Record<string, unknown> {
   return value !== null && typeof value === 'object' && !Array.isArray(value)
 }
 
+/**
+ * OMP 助手消息上的真实 token 用量 → ChatEvent `usage`。
+ *
+ * 字段含义来自 OMP 内核自身（`omp.exe` 内 `contextTokens ?? input + cacheRead + cacheWrite`
+ * 即本次请求真实消耗的上下文；`totalTokens = input + output + cacheRead + cacheWrite`）：
+ * - `input` 不含缓存命中，缓存命中单列在 `cacheRead`/`cacheWrite`。
+ * - 上游没给 usage、或本消息是中止/错误终态时返回 null，不产生事件、不估算。
+ */
+function readOmpUsage(message: unknown): TokenUsage | null {
+  if (!isRecord(message) || message.role !== 'assistant') return null
+  if (message.stopReason === 'aborted' || message.stopReason === 'error') return null
+  const usage = message.usage
+  if (!isRecord(usage)) return null
+  const count = (value: unknown): number | undefined =>
+    typeof value === 'number' && Number.isFinite(value) && value >= 0 ? value : undefined
+  const input = count(usage.input) ?? 0
+  const output = count(usage.output) ?? 0
+  const cacheRead = count(usage.cacheRead) ?? 0
+  const cacheWrite = count(usage.cacheWrite) ?? 0
+  const inputTokens = count(usage.contextTokens) ?? input + cacheRead + cacheWrite
+  if (inputTokens === 0 && output === 0) return null
+  const totalTokens = count(usage.totalTokens) ?? input + output + cacheRead + cacheWrite
+  return { inputTokens, outputTokens: output, totalTokens, ...(cacheRead > 0 ? { cachedTokens: cacheRead } : {}) }
+}
+
 function containsBinaryPayload(value: unknown, depth = 0): boolean {
   if (depth > 4 || value === null || typeof value !== 'object') return false
   if (

src/main/gateway/index.ts

@@ -10,7 +10,7 @@
  * 模型路由、上下文裁剪、工具编排由上层（agent/loop.ts）负责。
  */
 
-import type { GatewayConfig, ToolSpec } from '@shared/types'
+import type { GatewayConfig, TokenUsage, ToolSpec } from '@shared/types'
 import { resolveOpenAIEndpoint } from '@shared/openai-endpoint'
 import { parseSse } from './sse'
 import { buildResponsesRequest, parseResponsesStream } from './responses'
@@ -34,6 +34,7 @@ export type GatewayDelta =
   | { type: 'text'; text: string }
   | { type: 'reasoning'; text: string }
   | { type: 'tool_calls'; calls: WireToolCall[] }
+  | { type: 'usage'; usage: TokenUsage }
   | { type: 'finish'; reason: string | null }
 
 export interface GatewayStreamRequest {

src/main/gateway/responses.ts

@@ -149,6 +149,22 @@ export async function* parseResponsesStream(stream: ReadableStream<Uint8Array>,
         const response = object(payload.response)
         if (response.error || response.status !== 'completed' || !Array.isArray(response.output)) throw error('Responses 上游未返回合法成功终态')
         for (let i = 0; i < response.output.length; i++) yield* output({ output_index: i }, object(response.output[i]), true)
+        const usage = object(response.usage)
+        const inputTokens = usage.input_tokens
+        const outputTokens = usage.output_tokens
+        const totalTokens = usage.total_tokens
+        if (typeof inputTokens === 'number' && typeof outputTokens === 'number' && typeof totalTokens === 'number') {
+          const cachedTokens = object(usage.input_tokens_details).cached_tokens
+          yield {
+            type: 'usage',
+            usage: {
+              inputTokens,
+              outputTokens,
+              totalTokens,
+              ...(typeof cachedTokens === 'number' ? { cachedTokens } : {})
+            }
+          }
+        }
         completed = true
         break
       }

src/main/git.ts

@@ -0,0 +1,57 @@
+import { execFile } from 'node:child_process'
+import { promises as fs } from 'node:fs'
+import { promisify } from 'node:util'
+import type { GitBranchInfo } from '@shared/types'
+
+const execFileAsync = promisify(execFile)
+const GIT_TIMEOUT_MS = 5_000
+
+const outsideRepository = (): GitBranchInfo => ({ repo: false, branch: null, detached: false, head: null })
+
+function isUnavailableError(error: unknown): boolean {
+  if (!error || typeof error !== 'object') return false
+  const candidate = error as NodeJS.ErrnoException & { killed?: boolean }
+  return candidate.code === 'ENOENT' || candidate.code === 'ETIMEDOUT' || candidate.killed === true
+}
+
+async function runGit(cwd: string, args: string[]): Promise<string> {
+  const result = await execFileAsync('git', ['-C', cwd, ...args], {
+    windowsHide: true,
+    timeout: GIT_TIMEOUT_MS,
+    encoding: 'utf8',
+    maxBuffer: 64 * 1024
+  })
+  return result.stdout.trim()
+}
+
+/** Read the Git branch for a workspace without allowing Git failures to escape to IPC. */
+export async function readGitBranch(cwd: string): Promise<GitBranchInfo> {
+  try {
+    if (typeof cwd !== 'string' || cwd.length === 0) return outsideRepository()
+    const stat = await fs.stat(cwd)
+    if (!stat.isDirectory()) return outsideRepository()
+  } catch {
+    return outsideRepository()
+  }
+
+  try {
+    if (await runGit(cwd, ['rev-parse', '--is-inside-work-tree']) !== 'true') return outsideRepository()
+  } catch (error) {
+    return isUnavailableError(error) ? { ...outsideRepository(), unavailable: true } : outsideRepository()
+  }
+
+  try {
+    const branch = await runGit(cwd, ['symbolic-ref', '--short', '-q', 'HEAD'])
+    if (branch) return { repo: true, branch, detached: false, head: null }
+  } catch (error) {
+    if (isUnavailableError(error)) return { ...outsideRepository(), unavailable: true }
+  }
+
+  try {
+    const head = await runGit(cwd, ['rev-parse', '--short', 'HEAD'])
+    return { repo: true, branch: null, detached: true, head: head || null }
+  } catch (error) {
+    if (isUnavailableError(error)) return { ...outsideRepository(), unavailable: true }
+    return { repo: true, branch: null, detached: true, head: null }
+  }
+}

src/main/ipc.ts

@@ -11,7 +11,7 @@ import { BrowserWindow, app, dialog, ipcMain, shell, type OpenDialogOptions } fr
 import { randomUUID } from 'node:crypto'
 import { unlink, writeFile } from 'node:fs/promises'
 import { join } from 'node:path'
-import type { ChatEvent, ChatMessage, WindowState } from '@shared/types'
+import type { ChatEvent, ChatMessage, GitBranchInfo, WindowState } from '@shared/types'
 import { freezeAssistantModelMetadata } from '@shared/assistant-model'
 import type { ConfigPatchLike, EditAction, SendPayload, WorkspaceAttachResult } from '@shared/ipc'
 import { applyAssistantEvent } from '@shared/message-parts'
@@ -45,6 +45,7 @@ import * as experts from './capabilities/experts'
 import { createCapabilitySnapshot } from './capabilities/runtime'
 import type { McpServerInput } from '@shared/capabilities'
 import { agentMode, agentModeContextPatch, thinkingLevel } from './agent/mode-policy'
+import { readGitBranch } from './git'
 
 /** runId → 取消控制器 */
 const activeRuns = new Map<string, AbortController>()
@@ -266,6 +267,14 @@ export function registerIpc(getWindow: () => BrowserWindow | null): void {
     if (sessionId) return (await sessions.getSessionContext(sessionId)).cwd ?? await config.getWorkspaceRoot()
     return workspaces.workspaceRoot()
   }
+  ipcMain.handle('git:branch', async (_event, sessionId: unknown): Promise<GitBranchInfo> => {
+    if (typeof sessionId !== 'string' || !sessionId.trim()) return { repo: false, branch: null, detached: false, head: null }
+    try {
+      return await readGitBranch(await sessionRoot(sessionId))
+    } catch {
+      return { repo: false, branch: null, detached: false, head: null }
+    }
+  })
   ipcMain.handle('resources:openExternal', async (_event, input: string) => {
     const url = new URL(input)
     if (!['http:', 'https:'].includes(url.protocol)) throw new Error('链接协议不受支持')