{
  "callback_event_id": "callback_event_001",
  "callback_delivery_id": "callback_tokenops_001",
  "task_token": "task_tokenops_001",
  "event_type": "delivery_attempted",
  "event_state": "attempting",
  "attempt_number": 1,
  "http_status": 202,
  "response_body_ref": "callback_response_001",
  "failure_reason": null,
  "created_at": "2026-06-03T22:40:00-07:00",
  "payload": {
    "result_contract_url": "https://weverlabs.com/api/agents/tasks/task_tokenops_001/result-contract",
    "delivery_state": "delivered"
  }
}