[gravypod]

Would it be possible to avoid standardizing, and coupling, to a single ID type? It should be possible to locally store IDs as strings so the consumer of the IDs doesn't need to know how to parse it and the provider of the ID (the service) can choose whatever is natural.

For a content addressable file system it would be a hash, for another thing it might be an int, for another thing it might be a UUID, etc.

If you need to "validate" the ID is correct then the only way to do that is to contact the Source of Truth. Checking the syntax of the ID doesn't tell you if it is valid. That will introduce use-after-free like conditions in your system.