{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://aps.local/contracts/envelope.schema.json",
  "title": "EventEnvelope",
  "description": "服务端推给客户端的事件信封（协议 v1）。界面只依赖这一层，不感知引擎差异。",
  "$defs": {
    "status": {
      "type": "string",
      "enum": ["accepted", "pending-confirmation", "succeeded", "failed"]
    },
    "envelope": {
      "type": "object",
      "required": ["v", "seq", "ts", "sessionId", "type", "data"],
      "properties": {
        "v": { "const": 1, "description": "协议版本；改协议就加版本，不改这一版" },
        "seq": { "type": "integer", "minimum": 1, "description": "会话内单调递增；断点续传与去重靠它" },
        "ts": { "type": "integer", "description": "发生时间，整数毫秒（ADR-0007）" },
        "sessionId": { "type": "string", "minLength": 1 },
        "runId": { "type": "string", "description": "一次运行（回合）的标识；同会话可先后多个 run" },
        "type": { "type": "string" },
        "data": { "type": "object" }
      },
      "additionalProperties": false
    }
  }
}