> ## Documentation Index
> Fetch the complete documentation index at: https://docs.trynito.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Request IDs

> The X-Request-ID trace header.

Every response carries `X-Request-ID`. It ties a request to its log and trace records and is the fastest way to get support on a specific call.

| Step | Behavior |
| - | - |
| You send `X-Request-ID` | Sanitized: capped at 128 characters, charset `[A-Za-z0-9._:-]`. Characters outside the set are stripped, so send a UUID or a clean token. |
| You omit it | The gateway generates one: 16 random bytes, hex-encoded. |
| Response | The resulting ID is echoed in the `X-Request-ID` header and attached to logs and traces. |

Record it alongside your own request logs on every call.

`X-Request-ID` does not affect billing. `Idempotency-Key` is a separate header, validated as a UUID and not used to deduplicate.

## Related

* [Headers](/api/api-reference/overview/headers)
* [Debugging requests](/api/api-reference/errors-and-rate-limits/debugging-requests)


This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.