> For the complete documentation index, see [llms.txt](https://docs.navigaglobal.com/navigaid/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.navigaglobal.com/navigaid/integrations/service-integration/imsg-request-information.md).

# IMSG and headers

## Headers added by IMSG

| Header                | Description                                                                                                                                          | Removed by SAL |
| --------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------- | :------------: |
| **authorization**     | Contains the service token.                                                                                                                          |       Yes      |
| **x-imid-req-id**     | A unique id for the request. Used for debugging purposes.                                                                                            |       Yes      |
| **x-imid-token**      | Contains the IMID token if `INCLUDE_IMID_TOKEN_IN_REQUEST` is set to `true`.                                                                         |       Yes      |
| **x-forwarded-for**   | Used for identifying the originating IP address of the client. If included in the request, the original value will be prepended to the final header. |       No       |
| **x-forwarded-port**  | Used for identifying the port that the client used to connect. If included in the request, the original value will be used.                          |       No       |
| **x-forwarded-proto** | Used for identifying the protocol *(HTTP or HTTPS)* that the client used to connect. If included in the request, the original value will be used.    |       No       |
| **x-forwarded-host**  | Used for identifying the original host requested by the client. If included in the request, the original value will be used.                         |       No       |

{% hint style="info" %}
Any headers not in the list will be forwarded to the service unmodified.
{% endhint %}