llm-chat-completions-server 0.1a0

Simon Willison released llm-chat-completions-server 0.1a0, a plugin that exposes LLM models via an OpenAI Chat Completions-compatible endpoint. The plugin leverages content-addressable logs in LLM 0.32rc1 to de-duplicate conversation messages using hashes. GPT-5.6 Sol wrote the entire plugin code.

Release: llm-chat-completions-server 0.1a0 https://github.com/simonw/llm-chat-completions-server/releases/tag/0.1a0 A key goal of the new content-addressable logs in LLM 0.32rc1 https://simonwillison.net/2026/Jul/30/llm-rc1/ was being able to support OpenAI Chat Completion style requests where each incoming message extends the previous conversation, like this: curl http://localhost:8002/v1/chat/completions \ -H 'Content-Type: application/json' \ -d '{ "model": "qwen3.5-4b", "messages": {"role": "user", "content": "Capital of France?"}, {"role": "assistant", "content": "Paris."}, {"role": "user", "content": "Germany?"} }' Here the conversation state is tracked by the client, so each of these requests gets longer and longer. The new schema design in LLM is designed to de-duplicate these using hashes of the individual message parts. To test that out, I built this plugin: uv tool install llm --pre llm install llm-chat-completions-server llm chat-completions-server -p 9001 Running this starts a localhost server on port 9001 that exposes your full collection of LLM models from any plugins you have installed using a ChatGPT Completions compatible endpoint. GPT-5.6 Sol wrote the whole thing https://gist.github.com/simonw/53be513c1bd4a29a7aa480d9bde9b4a5 - it turns out it knows the OpenAI Chat Completions API shape really well.