openinverter-mcp

MCP server for openinverter / EV-CAN work: inspect openinverter parameter databases, decode and encode CAN frames via DBC files, and analyze recorded CAN logs — from Claude Code, Claude Desktop, or any MCP client.

Built for DIY EV builders (Leaf/Tesla drive units, stm32-sine firmware). No CAN hardware required: the DBC, log, and param-DB lanes are fully usable standalone on files. Live device access exists but is deliberately locked behind a feature flag (see Safety).

Install

Requires Python 3.10+.

pip install openinverter-mcp        # once published; from a clone:
git clone <this repo> && cd openinverter-mcp
uv sync                             # or: pip install -e .

Register with Claude Code

From a clone (project-scoped .mcp.json in this repo already does this):

claude mcp add openinverter -- uv run --directory C:/path/to/openinverter-mcp openinverter-mcp

Once on PyPI, no clone needed:

claude mcp add openinverter -- uvx openinverter-mcp

Then in a session: "load assets/sample.dbc and decode 0x156 701C2D2ED40D4A00".

Tools

Handles (dbc:1, log:1, paramdb:1) are returned by the load tools; every tool that takes a handle also accepts a file path directly.

SavvyCAN users: export captures as candump (.log) for log_open.

Safety model

Writing parameters can command a physical inverter, so param_write is safe by construction — three independent latches:

1. The server must be started with OPENINVERTER_MCP_ENABLE_DEVICE=1 before any physical CAN interface can be opened at all (the virtual interface is always allowed).
2. param_write requires an explicit device handle from device_connect.
3. param_write requires confirm: true, and its refusal text instructs the model to obtain the human's explicit confirmation of the exact write first.

Everything is validated (writability, range, enum/bitfield labels) before any bus traffic. Firmware save/reset/start/stop commands are not exposed at all. Values written go to RAM only.

Bundled sample assets

assets/ ships a synthetic, MIT-licensed trio (regenerate with python assets/generate.py): sample.dbc (EV-style messages), sample-candump.log (10 s synthetic drive, 405 frames), sample-paramdb.json (openinverter param DB with real stm32-sine parameter facts). See ATTRIBUTION.md for licensing of dependencies and asset provenance.

Development

uv sync --extra dev
uv run pytest          # 33 tests incl. a real stdio MCP end-to-end drive

Design: specs/DESIGN.md. Research notes: specs/api-research.md. License: MIT.