email.received

When it is emitted

OpenSend emits this event after the standalone ingester accepts an inbound provider notification, parses the raw MIME message, resolves the recipient to one tenant, stores the received email row, and commits attachment metadata. The event is not emitted for malformed messages, duplicate provider events, unrouteable messages, oversized messages, storage failures, or messages blocked by hosted quota.

Recommended payload

{
  "type": "email.received",
  "created_at": "2026-05-10T00:00:00.000Z",
  "data": {
    "id": "6f6f8b7e-534f-4b62-b0c1-64b79e45f3c2",
    "from": "support@example.com",
    "to": ["agent@inbound.example.com"],
    "subject": "New support request",
    "created_at": "2026-05-10T00:00:00.000Z",
    "attachments": [
      {
        "id": "att_01",
        "filename": "invoice.pdf",
        "content_type": "application/pdf",
        "size": 1234
      }
    ]
  }
}

Keep the webhook payload metadata-only. Retrieve bodies with GET /emails/receiving/{id} and attachments with GET /emails/receiving/{id}/attachments/{attachmentId} after verifying the webhook signature.

Delivery and verification

OpenSend webhook deliveries use the same signing and retry guidance as other events. Verify the svix-id, svix-timestamp, and svix-signature headers before acting on the inbound email. See Verify webhook requests and Retries and replays.