Workflow stdio 协议

// 1. initialize
{"type":"control_request","request_id":"init","request":{"subtype":"initialize","hooks":{},"capabilities":{},"hasPrompt":true}}

// 2. 让 agent 起一次 workflow（模型将调用 `Workflow` 工具）
{"type":"user","message":{"role":"user","content":"run /deep-research topic=foo"}}

// 3. 全部停下（同时中止 workflow 与所有 sub-agent）
{"type":"control_request","request_id":"stop-1","request":{"subtype":"interrupt","session_id":"<sessionId>","reason":"user cancel"}}

{
  "type": "control_request",
  "request_id": "<客户端自选字符串>",
  "request": {
    "subtype": "interrupt",
    "session_id": "<sessionId>",
    "reason": "user cancel"
  }
}

import { spawn } from 'node:child_process';

const cbc = spawn('cbc', [
  '--input-format', 'stream-json',
  '--output-format', 'stream-json',
  '--permission-mode', 'bypassPermissions',
], { stdio: ['pipe', 'pipe', 'pipe'] });

const send = obj => cbc.stdin.write(JSON.stringify(obj) + '\\n');

let buf = '';
let sessionId;
const tasks = new Map(); // task_id -> { workflow_progress, status, notified }

cbc.stdout.on('data', chunk => {
  buf += chunk;
  const lines = buf.split('\\n'); buf = lines.pop();
  for (const line of lines) {
    if (!line.trim()) continue;
    let msg; try { msg = JSON.parse(line); } catch { continue; }

    if (msg.type === 'system' && msg.subtype === 'init') sessionId = msg.session_id;
    if (msg.type !== 'system') continue;

    if (msg.subtype === 'task_started' && msg.task_type === 'local_workflow') {
      tasks.set(msg.task_id, { workflow_progress: [], status: 'running', notified: false });
    }
    if (msg.subtype === 'task_progress' && Array.isArray(msg.workflow_progress)) {
      const t = tasks.get(msg.task_id);
      if (t) t.workflow_progress = msg.workflow_progress; // 权威快照
    }
    if (msg.subtype === 'task_updated') {
      const t = tasks.get(msg.task_id);
      if (t && msg.patch?.status) t.status = msg.patch.status;
    }
    if (msg.subtype === 'task_notification') {
      const t = tasks.get(msg.task_id);
      if (t) { t.status = msg.status; t.notified = true; }
    }
  }
});

send({ type: 'control_request', request_id: 'init',
  request: { subtype: 'initialize', hooks: {}, capabilities: {}, hasPrompt: true } });
send({ type: 'user', message: { role: 'user', content: '/deep-research topic=foo' } });

async function cancel() {
  if (!sessionId) return;
  send({ type: 'control_request', request_id: 'stop-' + Date.now(),
    request: { subtype: 'interrupt', session_id: sessionId, reason: 'user cancel' } });
  await new Promise(resolve => {
    const check = () => {
      const stillRunning = [...tasks.values()].some(t => !t.notified);
      if (!stillRunning) resolve();
      else setTimeout(check, 200);
    };
    check();
  });
}

{
  "type": "system",
  "subtype": "task_started",
  "task_id": "<uuid>",
  "tool_use_id": "<toolUseId>",
  "task_type": "local_workflow",          // ← workflow 任务的判别器
  "workflow_name": "path:simple.workflow.js",
  "description": "<workflow description>",
  "uuid": "<messageUuid>",
  "session_id": "<sessionId>"
}

{
  "type": "system",
  "subtype": "task_progress",
  "task_id": "<uuid>",
  "tool_use_id": "<toolUseId>",
  "description": "<workflow description>",
  "usage": { "total_tokens": 0, "tool_uses": 0, "duration_ms": 0 },
  "workflow_progress": [
    { "type": "workflow_phase", "index": 1, "title": "Gather" },
    { "type": "workflow_agent", "index": 1, "agentId": "v2:<hash>",
      "state": "start", "startedAt": 178547..., "label": "child-1",
      "phaseTitle": "Gather", "phaseIndex": 1 }
  ],
  "uuid": "<messageUuid>",
  "session_id": "<sessionId>"
}

{"type":"system","subtype":"task_updated","task_id":"<id>","patch":{"status":"completed","end_time":178547...}}

{"type":"system","subtype":"task_notification","task_id":"<id>",
 "status":"completed",             // 或 "failed" / "stopped"
 "summary":"<summary>","output_file":"...","usage":{...}}