ForgeLab
A JSON intermediate representation plus MCP server so AI agents can design hardware, mechanical parts, and 3D models once and export to real tool files such as KiCad, FreeCAD, and glTF.
What it does and how it connects
ForgeLab lets AI agents design hardware, mechanical parts, and 3D models and export them to real tool files without ever touching a proprietary format. Its pitch is the LLVM of design: one JSON intermediate representation that every tool imports and exports. The domains covered are hardware in KiCad, mechanical CAD in FreeCAD, and 3D and game assets in Blender and glTF.
Installation is one command per agent for Claude Code, Codex CLI, Hermes Agent, and OpenClaw, each registering the MCP server over stdio against the same install in ~/.forgelab/venv. A forgelab init command prints an mcpServers config block for agents with no CLI of their own, and forgelab update upgrades the shared install for all agents at once.
The README example asks the agent to design a wireless temperature sensor with ESP32, DHT22, USB-C power, and a 3D-printable enclosure, and ForgeLab produces a complete project: KiCad PCB plus a FreeCAD enclosure sized to fit the board plus a Blender product render script plus a BOM, all from one prompt and all dimensionally coherent through a shared project file.
Alternatives
Compare side by side- kicad-mcp-pro
A profile-gated MCP server for KiCad with read-only review, build, and manufacturing profiles, rather than a JSON intermediate representation spanning KiCad, FreeCAD, and glTF.
- freecad-mcp (neka-nat)
The most widely used FreeCAD MCP server, with an addon plus server split and FEM analysis, rather than a JSON intermediate representation spanning KiCad and FreeCAD.
- PartCAD
A package manager for parametric CAD parts versioned through git, rather than a JSON intermediate representation plus MCP server.
- tscircuit
Designs boards in TypeScript and React (TSX) in a browser or CLI workflow, rather than a JSON intermediate representation plus MCP server.
- atopile
A code-first language and compiler for electronics, rather than a JSON intermediate representation plus MCP server.
Recurring errors it addresses
Error Index entries this tool is built to reduce or work around.
- A CAD agent bridge's screenshot tool refused any image over a 50KB socket frame, so every real model screenshot was dropped, and images that did fit arrived as base64 text inside JSON instead of real image blocks. The agent's only visual feedback channel was dead for production-scale models.Error Index
- A FreeCAD MCP bridge's autosave-before-call rewrote the active document on every tool call even with zero unsaved changes, stamping phantom diffs onto git-tracked CAD files. Agent activity pollutes version control with edits no human authored.Error Index
- A KiCad MCP bridge normalizes DRC, connectivity, and geometry into its own output format, and that normalized output can silently disagree with the native KiCad engine. The maintainer had to build seeded false-PASS and false-FAIL tests because the bridge layer cannot be trusted as engineering truth on its own.Error Index
- An engineer running Claude Code against KiCad found the agent kept repeating a stale claim of 19 DRC violations that lived on in prose docs. MCP tool summaries cannot be treated as live numbers; only DRC message text and actual exports are authoritative.Error Index
- A FreeCAD MCP bridge silently ignored parameters the client materialized from JSON-Schema defaults, so box(size=20) produced a default 10mm shape. The agent believes it built the requested geometry while the model is something else entirely.Error Index
Sources
Not verified
- No GitHub releases exist, so latest release fields are null.
- No independent user voice found: the repo has no public issues.
- Pricing: none stated on the repo.
Last verified November 6, 2026. Listings are informational. The evidence score measures public, verifiable evidence and is not an endorsement or a compatibility claim.