lmstudio-mcp

An MCP server that lets Claude Code delegate easy, mechanical tasks (summaries, boilerplate, reformatting, test data) to local models running in LM Studio — keeping Claude as the orchestrator while cheap work runs locally.

Tools

Tool	Purpose
ask_local_model	Send a self-contained prompt to a local model. Optional model, system, temperature, max_tokens.
list_local_models	List models currently available in LM Studio.

The ask_local_model tool description tells Claude when to delegate (mechanical, low-stakes tasks with small context) so delegation happens automatically once the server is installed.

Requirements

• Node.js 18+
• LM Studio running with its local server enabled (default http://localhost:1234) and at least one chat model loaded

Setup

git clone https://github.com/zmagyar/lmstudio-mcp.git
cd lmstudio-mcp
npm install

# register with Claude Code (user scope = available in all projects)
claude mcp add --scope user lmstudio -- node "$(pwd)/index.js"

Start a new Claude Code session and try: "use the local model to summarize this file".

Configuration

Set via environment variables (e.g. in the server's entry in ~/.claude.json):

Variable	Default	Purpose
LMSTUDIO_BASE_URL	http://localhost:1234/v1	LM Studio API endpoint
LMSTUDIO_DEFAULT_MODEL	openai/gpt-oss-120b	Model used when Claude doesn't specify one

Set LMSTUDIO_DEFAULT_MODEL to a model you actually have loaded — run lms ls or check the LM Studio UI.

Making delegation automatic

Out of the box, Claude only uses the tools when you ask ("use the local model to…"). Two extra steps make it delegate small tasks on its own, without prompting you each time — sample files for both are in examples/:

1. Standing instructions — append the contents of examples/CLAUDE.md.sample to your ~/.claude/CLAUDE.md (create it if missing). It's loaded into every session and tells Claude when to delegate: mechanical, low-stakes tasks like log summaries, boilerplate, and reformatting — and when not to.

2. Pre-approved permissions — merge the permissions block from examples/settings.json.sample into your ~/.claude/settings.json, so the tool calls don't stop at a permission prompt. If you already have a permissions.allow array, just add the two entries to it.

Both changes take effect in your next Claude Code session. Try "summarize the last 200 lines of this build log" — the lmstudio tool should fire without being asked for.

Note that delegation is judgement-based: Claude decides per-task using those instructions, so tune the wording in your CLAUDE.md if it delegates too eagerly or too rarely.

License

MIT