I think you’d have to have a fairly awkward API design in order for this to be an issue. For example, if “POST /posts” does something else, like flags a post fo

I think you’d have to have a fairly awkward API design in order for this to be an issue. For example, if “POST /posts” does something else, like flags a post for a moderator to review. That being said, I don’t see this feature being particularly beneficial either. Only the caches which observed the request could know to purge the cache. So you can’t actually rely on it for cache invalidation.