ABLE-MCP

Right-click MIDI tools for Ableton Live 12, plus an MCP server for .als analysis.

Two artifacts in one repo:

1. AbleMCP.ablx — a native Ableton Live 12 extension. Drag it in, right-click any MIDI clip, get 17 instant transformations. No Python, no LLM, no API key, no internet, no waiting.

2. able-mcp (Python) — an MCP server for parsing and analyzing .als project files offline. Plug into Claude Desktop / VS Code / Cursor and ask questions about your sets.

The extension (ship target for v0.1.0)

Built on @ableton-extensions/sdk 1.0.0-beta.0. Runs inside Live's own process — not Max for Live. Tested on Live 12.4.5b3.

Install

1. Download dist/AbleMCP.ablx

2. Open Live → Settings → Library → Extensions

3. Drag the .ablx file in

4. Restart Live

What you get

Right-click any MIDI clip (session or arrangement) → ABLE-MCP menu:

Every action also works on time-range selections in arrangement view — right-click a selection across one or more MIDI tracks and pick ABLE-MCP (range): …. Only notes inside the range are transformed.

Every action is a single Cmd-Z undo.

Why it's fast

These are pure deterministic functions running in-process. Typical action: ~1ms. No LLM call, no JSON round-trip, no network, no cost per click. The intelligence lives in the transform, not in a chat window.

Building from source

cd extension
npm install
npm run build      # tsc + esbuild → dist/extension.cjs
npm run package    # → ../dist/AbleMCP.ablx

The MCP server

Python 3.11, stdio transport. Parses Live's gzipped .als files and exposes structure as MCP tools. Useful when you want an LLM to read a project without opening Live.

Install

uv sync

Run

uv run able-mcp

Hook into a client

Claude Desktop — ~/Library/Application Support/Claude/claude_desktop_config.json:

{
  "mcpServers": {
    "able-mcp": {
      "command": "uv",
      "args": ["--directory", "/absolute/path/to/ABLE-MCP", "run", "able-mcp"]
    }
  }
}

VS Code (Copilot Chat) — your user or workspace mcp.json:

{
  "servers": {
    "able-mcp": {
      "command": "uv",
      "args": ["--directory", "/absolute/path/to/ABLE-MCP", "run", "able-mcp"]
    }
  }
}

Tools

Roadmap

• v0.2 — bring back the Ask-AI flow with persisted API key (Anthropic / OpenAI / Google / Ollama). The scaffolding is already in extension/src/llm.ts and extension/src/config.ts, pulled from v1 to keep the release tight.

• v0.3 — extension ↔ MCP-server bridge. The extension already runs a localhost WebSocket JSON-RPC server on 127.0.0.1:9831; the Python side just needs to consume it for read/write tools.

• v0.4 — audio-clip primitives (the audioclipactions.ts + wav.ts work is in tree, gated off until the chop-on-arrangement bug is solved).

Develop

uv run pytest         # Python tests
uv run ruff check .   # Python lint

Python tests use synthetic .als fixtures (gzipped XML) generated in tests/fixtures/init.py. When a real Live 12 file becomes available, drop it under tests/fixtures/real/ and add parity tests — the parser is best-effort against an undocumented schema.

Supply-chain hygiene

• uv.lock is committed; review every diff.

• All Python deps pinned with ==.

• The extension has exactly one runtime dep (@ableton-extensions/sdk), pinned in extension/package.json.

License

MIT (extension and Python server).