# Rivr-Webhook-Id on every callback from the platform

- Date: 2026-10-21
- Type: New
- Surface: /api/public, Webhooks
- What you need to do: Nothing.
- Address: https://developers.rivr.io/changelog/2026-10-21-webhook-id-on-callbacks

Every callback to an order's callbackUrl, and to a clinic's own webhook address, now carries the header Rivr-Webhook-Id: the same header, in the same form (a UUID), that your organisation's webhook endpoints get. It identifies the event. Every attempt to deliver the same event, retries included, carries the same value, and two different events carry different values, also when they concern the same order and have the same status. Store the values you have handled, and answer a callback you have already handled with 2xx without handling it again. The body and the other headers are unchanged, and the header is not part of the signature: Rivr-Signature still covers the timestamp and the body. In production since 2026-10-21 (platform release 2026.10.20.2531).