I used to play MUD's as a kid! I've got an LLM powered CLI MUD game slow brewing in my noggin but haven't started on it yet. I did build a multi-player chatgpt powered discord text-adventure bot which I think I'll eventually try to convert into a shared-universe game. I think all you really need is a little bit of state (like, if you were to walk up to an auction house and ask to see the items just pull it from a db and inject into context).