KiCad MCP Servers: Which One to Use and How to Set It Up

What a KiCad MCP server can actually reach

An MCP server is a small program your AI client starts on your machine. It lists tools, such as "place footprint" or "run DRC", and the model calls them as it works. A KiCad MCP server turns those calls into changes through three routes: KiCad's IPC API for live edits in a running PCB Editor, direct edits to the .kicad_sch and .kicad_pcb text files, and kicad-cli for ERC, DRC and exports.

The limits come from KiCad, not from the servers. KiCad's developer docs say KiCad 9 and 10 support the IPC API only in the PCB Editor, and only while the KiCad GUI is running. Schematic Editor support and headless use arrive in KiCad 11. So every server that edits schematics today does it by rewriting the schematic file, which is why some of them tell you to close and reopen KiCad to see the change. KiCad 9's release notes also say the IPC API will eventually replace the older Python bindings that several servers still use.

Which server to try first

On KiCad 10, if you want the AI to build and edit boards, start with KiCad MCP Pro or Konnect. KiCad MCP Pro installs with one command (uvx kicad-mcp-pro), starts in a 24-tool read-only profile, and documents setup for Claude Code, Claude Desktop, Codex, Cursor, VS Code and Gemini CLI. Its README is direct that its signal-integrity, power-integrity, EMC and thermal tools are first-order estimates, not field-solver results. Konnect is a single Rust binary that installs through KiCad's Plugin and Content Manager and talks to KiCad 10 over the IPC API, so board edits land in KiCad's own undo history. It is marked beta, and its AGPL-3.0 license is free for hobbyists, students, freelancers and open-source projects, with commercial licenses for businesses.

On KiCad 9, mixelpixx/KiCAD-MCP-Server is the project that ranks first on Google for "kicad mcp" and the one the long KiCad forum thread is about. It needs Node.js 18+, Python 3.11+ and KiCad's Python bindings, so installs have more moving parts, and its author says new development now happens in Konnect while the Python server stays maintained. If you only want the AI to read and review a design, Seeed Studio's server is the lightest choice: its README recommends doing design work in the KiCad GUI and using the server for analysis, validation and code generation.

blwfish/kicad-mcp is a small server with 18 tools, written by a model-railroad builder who designs his own boards with it and tests it with Claude Code on a Mac. lamaalrajih/kicad-mcp still appears in older lists and directories, but it has had no commits since October 2025.

Set it up with Claude Desktop, Claude Code or Codex

Whatever server you pick, commit the KiCad project to Git first so every AI edit can be diffed and reverted. For live PCB edits through the IPC API, turn the API on in KiCad under Preferences, Plugins, "Enable KiCad API".

Claude Code: register a stdio server with claude mcp add and put the server command after a double dash, for example: claude mcp add --env KICAD_MCP_PROJECT_DIR=/path/to/project --transport stdio --scope project kicad -- uvx kicad-mcp-pro. Keep another option between --env and the server name, because Claude Code reads a name that follows --env as one more variable. Project scope writes a .mcp.json you can commit; --scope user makes the server available in every project. Check it with claude mcp list.

Codex: codex mcp add kicad --env KICAD_MCP_PROJECT_DIR=/path/to/project -- uvx kicad-mcp-pro adds the same server to ~/.codex/config.toml, or to a trusted project's .codex/config.toml. Konnect registers with codex mcp add konnect -- /path/to/konnect --client codex, and konnect init --client codex installs its KiCad skills for Codex. Check with codex mcp list, or /mcp inside Codex.

Claude Desktop: add the server under "mcpServers" in claude_desktop_config.json, found at ~/Library/Application Support/Claude/ on macOS or %APPDATA%\Claude\ on Windows, then quit and restart the app. Claude Code does not read that file, so register servers there separately.

What works today, and what still breaks

The most detailed public test is JLCPCB's October 14, 2026 write-up. Claude Code with KiCad MCP Pro on KiCad 10.0.4 built a two-layer XL4015 buck converter that ended at 0 ERC violations and 0 DRC errors. The same log lists what went wrong on the way: the layout step stacked the units of a dual op-amp on top of each other, two overlapping net labels shorted two nets with only an ERC warning, a routing step used 0.35 mm edge clearance against a 0.5 mm rule and produced 7 DRC errors, part search results had to be rechecked against JLCPCB data, and Claude wrote its own grid router because no autorouter was available in that setup. The board was not fabricated or bench-tested.

Reports on the older Python servers are mostly about installs. The KiCad forum thread on KiCAD-MCP-Server includes failed builds and schematic tools that could not create new schematics (October 2025); the project has changed a lot since. Seeed Studio's README says its wiring tools may not always form electrical connections.

Reading and reviewing a design is the most reliable use today. Small two-layer boards can be built with close supervision. Whatever the model draws, compare the netlist to your intent pin by pin, because a clean ERC does not prove the schematic is what you meant.

Skills instead of a server

Not every AI-plus-KiCad setup needs MCP. aklofas/kicad-happy (MIT, v2.3.1) is a set of agent skills and Python scripts for Claude Code, Codex, GitHub Copilot CLI and others. It parses schematics, layouts and Gerbers and reviews the design, from power trees to connector ESD coverage, and it can also run as a GitHub Action that reviews pull requests.

Where ProtoFlow fits

ProtoFlow is not a KiCad MCP server. It is a free desktop PCB editor for Windows, macOS and Linux with the AI built in, and it reads and writes KiCad projects, so the AI works on your KiCad files with no server, Python environment or client configuration to maintain. Its Copilot has 50+ tools for direct schematic editing and takes a checkpoint before it changes anything, so a bad edit rolls back in one step.

ProtoFlow Studio, the AI agent, goes further: from a written brief it chooses parts, draws the schematic, places and routes the board, and runs ERC and DRC as it works. On LG AI Research's public PCBWorld-Bench, ProtoFlow Studio with Claude Opus 5.5 left all 99 small boards clean under KiCad DRC, each within a 30-minute limit, and 30 of 30 medium-board attempts clean (ten boards, three attempts each). That is evidence for those benchmark boards only, and you still review every result.

If you already pay for Claude Code or Codex, ProtoFlow's Max plan runs Max mode through your own Claude Code or Codex. The free plan includes the full editor with basic AI models and daily message limits. ProtoFlow's separate command-line tool, @protoflow/cli, covers sign-in and component catalog search with JSON output; it does not control KiCad.