洪 民憙 (Hong Minhee) 
@hongminhee@hollo.social · Reply to kopper :colon_three:'s post
@kopper Thanks for engaging with this—it helps me think it through more carefully.
Your point about making the split explicit at the protocol level is well taken. I can see how that matters especially for extensions: a lot of FEPs end up adding actor-global state for things that are really client concerns, and having a clearer boundary in the protocol might discourage that drift. That's a concrete benefit I hadn't fully appreciated.
On the interoperability question, I think I see where we differ. You're reframing the core promise of C2S as “reuse the same account across different interfaces,” whereas I'd been reading it as “connect any frontend to any server.” Those lead to quite different designs. I'm not sure which framing is more faithful to what C2S originally intended—maybe neither of us is wrong, and the spec was simply underspecified on this point.
That said, if account portability is the goal, I wonder whether C2S is really the right tool for it. FEP-ef61 and the Nomadic Identity approach both tackle that problem more directly, by making identifiers server-independent at the identity layer rather than standardizing the client–server protocol. It feels like a different layer of the problem altogether, and I'm not sure C2S can carry that weight on its own even with your proposed architecture.
The point about AP objects remaining AP objects through hydration is interesting though. I can see how that keeps the pieces composable even without a standardized client API. I'll have to think about that more.
