{
  "request": {
    "method": "POST",
    "url": "https://subscriber.example.com/athena-webhook",
    "headers": {
      "Content-Type": "application/fhir+json",
      "X-athena-Subscription-Id": "sub-789"
    },
    "body": {
      "resourceType": "Bundle",
      "type": "history",
      "timestamp": "2026-05-25T14:02:17Z",
      "entry": [
        {
          "fullUrl": "https://api.platform.athenahealth.com/fhir/r4/Patient/a-12345",
          "resource": {"resourceType": "Patient", "id": "a-12345"}
        }
      ]
    }
  },
  "response": {
    "status": 200,
    "note": "Subscriber must ACK with a 2xx within 2 seconds."
  }
}