{
  "id": "sample-001",
  "type": "heart_rate",
  "value": 72,
  "unit": "bpm",
  "observed_at": "2026-09-30T08:00:00Z",
  "received_at": "2026-09-30T08:04:00Z",
  "source": {
    "device": "example_watch",
    "record_id": "demo-record-001"
  },
  "status": "illustrative"
}