@fingerskier/pi-build123d

build123d CAD MCP plugin for Pi with a self-bootstrapping Python server

Packages

Package details

extensionskill

Install @fingerskier/pi-build123d from npm and Pi will load the resources declared by the package manifest.

npm report
$ pi install npm:@fingerskier/pi-build123d
Package
@fingerskier/pi-build123d
Version
2026.5.7
Published
May 7, 2026
Downloads
248/mo · 5/wk
Author
fingerskier
License
MIT
Types
extension, skill
Size
59.2 KB
Dependencies
1 dependency · 0 peers
Pi manifest JSON
{
  "extensions": [
    "./extensions/build123d.ts"
  ],
  "skills": [
    "./skills"
  ]
}

Security note

Pi packages can execute code and influence agent behavior. Review the source before installing third-party packages.

README

build123d Pi Plugin

Pi package port of build123d-claude-plugin.

This package bundles the upstream Python MCP server source and a Pi extension that exposes its tools with a build123d_ prefix. The first MCP start creates a private venv under ~/.pi/agent/data/build123d/venv, installs this package into it, then runs build123d-mcp.

Install

pi install npm:@fingerskier/pi-build123d
# local workspace clone
pi install ./packages/pi-build123d
# one run only
pi -e npm:@fingerskier/pi-build123d

Host requirement: Python 3.10+ available as python (or set BUILD123D_PYTHON).

Tools

Run build123d_mcp_status in Pi to list loaded tools. Expected tools include:

  • build123d_execute_build123d
  • build123d_export_stl
  • build123d_export_step
  • build123d_render_image
  • build123d_list_models
  • build123d_get_model_info
  • build123d_delete_model

Configuration

  • BUILD123D_MCP_AUTOLOAD=0 disables startup MCP discovery.
  • BUILD123D_OUTPUT_DIR=./cad-output controls export/render output.
  • BUILD123D_PI_DATA=/path/to/data controls the venv/cache directory.
  • BUILD123D_PYTHON=python3 selects the Python executable.

Skill and Reference

  • /skill:build123d loads CAD workflow guidance.
  • docs/BUILD123D_REFERENCE.md is copied from the upstream Claude guide.

Upstream Notes

See README.upstream.md for the original Claude plugin documentation.