### Send POST request with json body
POST https://synapse.hyteck.de/_matrix/maubot/plugin/alertbot/webhook/!zOcbWjsWzdREnihgeC:hyteck.de
Content-Type: application/json

{
  "receiver": "matrix",
  "status": "firing",
  "alerts": [
    {
      "status": "firing",
      "labels": {
        "alertname": "InstanceDown",
        "environment": "monitoring.example.com",
        "instance": "webserver.example.com",
        "job": "node_exporter",
        "severity": "critical"
      },
      "annotations": {
        "description": "webserver.example.com of job node_exporter has been down for more than 5 minutes.",
        "summary": "Instance webserver.example.com down"
      },
      "startsAt": "2022-06-23T11:53:14.318Z",
      "endsAt": "0001-01-01T00:00:00Z",
      "generatorURL": "http://monitoring.example.com:9090/graph?g0.expr=up+%3D%3D+0\u0026g0.tab=1",
      "fingerprint": "9cd7837114d58797"
    }
  ],
  "groupLabels": {
    "alertname": "InstanceDown"
  },
  "commonLabels": {
    "alertname": "InstanceDown",
    "environment": "monitoring.example.com",
    "instance": "webserver.example.com",
    "job": "node_exporter",
    "severity": "critical"
  },
  "commonAnnotations": {
    "description": "webserver.example.com of job node_exporter has been down for more than 5 minutes.",
    "summary": "Instance webserver.example.com down"
  },
  "externalURL": "https://alert.example",
  "version": "4",
  "groupKey": "{}:{alertname=\"InstanceDown\"}",
  "truncatedAlerts": 0
}