Watcher webhook body How to build a json format?

  "actions": {
    "mywebhook": {
      "webhook": {
        "method": "POST",
        "url": "https://xxxxx,
        "headers": {
          "Content-Type": "application/json"
        },
        "body": {
              "touser" : "username",
              "msgtype" : "text",
              "agentid" : 100000,
              "text" : {
                "content" : "xxxx"}
             }
        }
    }
  }
}

kibana shows error
image

Request sample

Problem has been solved