https://www.securecodebox.io/docs/contributing/integrating-a-hook/hook has an info box stating

Maybe you notice that in line 5 ENVs are used. If you also need ENVs or Volumes see INSERT-LINK-HERE.

There should probably be an actual link there: https://github.com/secureCodeBox/documentation/blob/9d8e910e7c891b88f9187fcfd562381a0424721a/docs/contributing/integrating-a-hook/hook.md?plain=1#L155-L158

The values.yaml page for integrating scanners links to https://kubernetes.io/docs/tasks/inject-data-application/define-environment-variable-container/, but not without a bit more background information.