curl --request GET \
  --url https://api.healos.ai/ext-api/v1/appointments/{appointmentId} \
  --header 'X-API-Key: <api-key>'

{
  "data": {
    "id": "f47ac10b-58cc-4372-a567-0e02b2c3d479",
    "patient_id": "1743552000000",
    "patient_name": "Maria Santos",
    "appointment_type": "Initial Evaluation",
    "visit_type": "Telehealth",
    "start_at": "2026-04-15T14:00:00.000Z",
    "duration_minutes": 50,
    "notes": "New patient intake. Please complete forms beforehand.",
    "status": "SCHEDULED",
    "created_at": "2026-04-01T10:00:00.000Z",
    "updated_at": "2026-04-01T10:00:00.000Z",
    "repeat_rule": {
      "frequency": "WEEKLY",
      "interval": 1,
      "end_date": "2026-07-15"
    },
    "external_id": "PARTNER-APPT-789"
  }
}