io.github.pzfreo/build123d-mcp
build123d MCP
Is the build123d MCP server down? No. It answered initialize and tools/list in the probe of 2026-11-02.
AI-driven 3D CAD via build123d: execute, render, measure, and export geometry interactively.
alive probed 2026-11-15 · unchanged since 2026-11-02
- Run it
- uvx build123d-mcp@0.3.91 (stdio, probed in a container with the network off)
- Host
- pypi.org
- Reports itself as
- build123d-mcp 0.3.91
- Capabilities
- prompts, resources, tools
- Instructions
- 1 767 characters
- Of a 1M window
- 1.9 % of a 1M context window
- Count
- 19k tokens in Claude Opus 5.5, exact, measured 2026-11-02. With the Claude Code prefix mcp__…__ on each tool name: 20k. The o200k_base estimate is 11k. Counted again when the tool definitions change. Method.
- Repository
- https://github.com/pzfreo/build123d-mcp
- Registry
- active, updated 2026-10-15 · registry entry
- Changes
- 2 recorded, reachable in 1 of them. A row is added when the result, the tool count or the cost changes.
Most expensive tools
The Claude column scales the o200k estimate of each tool by this server's ratio of exact to estimate, 1.69×.
| Tool | ≈ Claude tokens | o200k estimate | Share of this server |
|---|---|---|---|
| suggest_view_layout | 1 287 | 761 | 7 % |
| lint_drawing | 918 | 543 | 5 % |
| execute | 837 | 495 | 4 % |
| inspect_drawing | 748 | 442 | 4 % |
| analyze_printability | 737 | 436 | 4 % |
Compare this server with others.
More servers
Other registry entries on pypi.org, the ones next to this name; all of them.
- Scholar MCP io.github.pvliesdonk/scholar-mcp · crashed on start
- Local Coding Agent io.github.pvnc228/local-coding-agent · needs args
- pyeconomics io.github.pyeconomics-dev/pyeconomics · needs args
- io.github.pythia-the-oracle/pythia-oracle-mcp · alive
- io.github.q1023884985/visiongemma · needs env
- Task Checkpoint io.github.qddfxp/task-checkpoint-mcp · alive
- TAR Engine io.github.qingxuantang/tar-engine · needs args
- io.github.qkrehgk1-wq/mcp-korea-worklife · alive
Servers that mention build123d or interactively or geometry.
- b123d-print io.github.KD5RYN/b123d-print · crashed on start
- GEOMETRY app.geometry/mcp · alive
- a2a2p — Agent-to-Agent-to-Physical com.a2a2p/a2a2p · alive
- com.htagai/htag-spatial · needs auth
- Caliper fit.caliper/caliper · alive
- Nexus Alpha Geometry io.github.SpearmanMODE/nexus-alpha-geometry · not MCP
- io.github.jdhart81/smartscale · alive
- Coordinates io.github.pipeworx-io/coordinates · alive
History
We add a row when the result changes. A server with no change keeps its last row.
| Probed | Result | Init | Tools | Claude | o200k |
|---|---|---|---|---|---|
| 2026-11-02 08:24 | alive | 1.6 s | 48 | 19k | 11k |
| 2026-10-19 07:00 | install failed |
Badge for the README
The result of the latest probe, the tool count and the token cost. The feed has an entry for every probe that changed them.
A mail when this server changes
Stops answering, comes back, tool set or cost changes. One confirmation mail first, a stop link in every mail.
For the publisher
- This server is in the heaviest 10 % of the registry. Shorter descriptions, fewer optional parameters and fewer tools cut the cost. The command npx mcpcost --url <endpoint> --tools 50 lists every tool with its cost.