This could be, centrally configured deprecation information by version. It would be added to a response to endpoints for the deprecated version. There are two relevant specs: - [RFC 9745](https://datatracker.ietf.org/doc/rfc9745/) The Deprecation HTTP Response Header Field - [RFC 8594](https://datatracker.ietf.org/doc/html/rfc8594) The Sunset HTTP Header Field We could support use of those, but also leave it flexible to customize.