Dead Letter Queue

Inspect permanently failed deliveries in the dead letter queue, filter them by binding or error code, and replay individual items or discard them.

Deliveries that exhaust all retry attempts are moved to the dead letter queue (DLQ). Items in the DLQ can be inspected, replayed (enqueues a fresh attempt), or deleted.

The DLQ is the terminal state for failed deliveries. Common error codes include connector_5xx (destination returned a server error), auth_failed (invalid credentials), ssrf_blocked (destination URL resolves to a private network), and payload_too_large (payload exceeds the cap). Non-retryable errors (auth_failed, ssrf_blocked) skip the retry ladder and go directly to the DLQ.

Response

{
  "data": [
    {
      "id": "f6a7b8c9-d0e1-2345-fabc-567890123456",
      "binding_id": "d4e5f6a7-b8c9-0123-defa-345678901234",
      "event_id": "98750",
      "last_item_id": "e5f6a7b8-c9d0-1234-efab-456789012345",
      "error_code": "connector_5xx",
      "error_message": "HTTP 503",
      "attempts": 7,
      "created_at": "2024-09-16T03:00:00.000Z"
    }
  ]
}

Errors

Response

{
  "replayed": true
}

Errors

Response

{
  "dismissed": true
}

Errors

Bulk replay

POST /v1/delivery/dlq/replay-all is the bulk form of the per-item replay: every dead-letter row matching the optional binding_id and error_code filters is deleted and re-enqueued as a fresh attempt-1 delivery, so the full retry ladder restarts for each. With no filters it replays the whole DLQ. Idempotency keys are unchanged across the replay, so receivers that dedupe on X-Talonic-Idempotency-Key are safe against duplicates.