If you can't imagine how stuff like this would be possible, "then", as Roy Fielding quipped, "most likely you just haven’t defined enough resources".

An alternative, don't create a service. Let the Web be the platform.

If I'm a contributor to the project, then the extension's about.html (or whatever) should both credit me and at my option include a link to the place where I publish or link to useful scripts. This goes for all contributors. The way to share would be to (a) publish their scripts somewhere online and (b) contribute to the project and add their entry to about.html. Alternatively, for people not interested in contributing (and to maintain code quality and avoid poorly aligned incentive structures), the project itself can keep a simple static page up to date, linking to various others' pages as the requests to do so come in.

OpenAPI links are different than HAL links or HATEOAS links, because these links mainly specify the "flow" throughout the API methods.

This means that these links mostly document the way this API can be traversed.