It started, as these things do, with a shortcut I was certain would work.
I’ve been building SwiftAgents, my Swift framework for talking to language models, and one of the local providers it supports is LM Studio — the app a lot of us reach for to run models on our own Macs. LM Studio recently grew support for the newer “Responses” API, the OpenAI-style endpoint that can remember a conversation for you. Instead of re-sending the whole chat history on every turn, you send only the new message plus a little breadcrumb — previous_response_id — that tells the server “you already remember the rest.” Less data over the wire, less bookkeeping on the client. An obvious win, and I wanted it in SwiftAgents.
