Can we extend in-built RPCs with custom proto files?

I know that we can register custom RPC’s directly doing something like

if err := initializer.RegisterRpc("some-static-string", SomeRpc); err != nil {
	return err

This is fine, but I’m looking for alternative solutions to make sure we can keep some-static-string in sync across the backend & client less manually. Given the benefits of gRPC (and the fact that it is used under the hood in both Nakama Common and the apigrpc folder in Nakama is there any scope, or workflow for adding proto files of our own in addition to the hard implementation of the relevant rpc calls?

Are there any other best practices, or could anyone offer up any solutions they have come up with in this respect?