google home action sync不适用于有效的json响应

{
  "requestId": "请求ID",
  "payload": {
    "agentUserId": "用户ID",
    "devices": [
      {
        "id": "设备ID",
        "type": "设备类型",
        "traits": ["设备特性"],
        "name": {
          "defaultNames": ["默认名称"],
          "name": "设备名称",
          "nicknames": ["设备昵称"]
        },
        "willReportState": false,
        "deviceInfo": {
          "manufacturer": "制造商",
          "model": "型号",
          "hwVersion": "硬件版本",
          "swVersion": "软件版本"
        },
        "attributes": {
          // 设备特定属性
        }
      }
    ]
  }
}

const functions = require('firebase-functions');
const { smarthome } = require('actions-on-google');

const app = smarthome();

app.onSync((body, headers) => {
  return {
    requestId: body.requestId,
    payload: {
      agentUserId: "123",
      devices: [{
        id: "washer",
        type: "action.devices.types.WASHER",
        traits: [
          "action.devices.traits.OnOff"
        ],
        name: {
          defaultNames: ["My Washer"],
          name: "Washer",
          nicknames: ["Washer"]
        },
        willReportState: false,
        deviceInfo: {
          manufacturer: "Example Manufacturer",
          model: "Example Model",
          hwVersion: "1.0",
          swVersion: "1.0.1"
        },
        attributes: {}
      }]
    }
  };
});

exports.smarthome = functions.https.onRequest(app);