Shapr3d Mcp

Shapr3D MCP Server

An MCP server that lets AI assistants (Claude, etc.) model real CAD parts and work with Shapr3D.

How it works

Shapr3D has no public API or scripting interface (it's a long-standing community request). So this server takes the only robust route:

1. Real CAD kernel inside the server. Models are built programmatically

with build123d on the OpenCascade B-rep kernel — the same class of geometry Shapr3D uses (Parasolid-like solids, not meshes).

1. STEP file exchange. Generated models export as STEP, which Shapr3D

imports as fully editable solid bodies. Files you export from Shapr3D (STEP/IGES/STL) can be inspected, modified, and converted.

1. macOS app bridge. Tools to launch Shapr3D, open files in it, check its

state, and screenshot its window for visual feedback.

AI assistant ──MCP──▶ this server ──build123d/OCCT──▶ model.step ──▶ Shapr3D
                          ▲                                            │
                          └────────── STEP/STL export from app ◀───────┘

Tools

| Tool | Purpose | |---|---| | create_model | Build a model from a build123d script (optionally fed by a shared params_file), export STEP/STL/3MF/glTF/GLB/BREP | | modify_model | Import an existing file (e.g. Shapr3D STEP export), edit it in code, re-export | | detect_clash | Pairwise interference check between solids (assembly/keep-out verification) | | inspect_model | Solids, bounding box, volume, face/edge counts of a STEP/IGES/STL/BREP/3MF file | | convert_model | Read STEP / IGES / STL / BREP / 3MF, write STEP / STL / 3MF / glTF / GLB / BREP | | render_preview | Shaded isometric PNG preview without opening any app | | list_models | List files in the models workspace | | open_in_shapr3d | Open a file in Shapr3D (STEP imports as editable bodies) | | activate_shapr3d / shapr3d_status | Launch / check the app | | screenshot_shapr3d | Capture the Shapr3D window | | build123d_guide | Modeling syntax cheat sheet for the AI |

Setup

Requires macOS, uv, and Shapr3D installed.

uv sync

Claude Code

A project-scoped [.mcp.json](.mcp.json) is included — opening this folder in Claude Code picks it up automatically. To register it globally:

claude mcp add shapr3d -s user -- uv run --directory "" shapr3d-mcp

Claude Desktop

Add to ~/Library/Application Support/Claude/claude_desktop_config.json:

{
  "mcpServers": {
    "shapr3d": {
      "command": "uv",
      "args": ["run", "--directory", "", "shapr3d-mcp"]
    }
  }
}

Typical workflow

1. Ask the AI to model something ("design a wall bracket for a 2-inch pipe,

4 mounting holes for M5 bolts").

1. It writes a build123d script via create_model, checks it with

render_preview, and opens the STEP in Shapr3D via open_in_shapr3d.

1. You confirm the Import Preferences dialog in Shapr3D (Quality is fine;

STEP carries mm units) and edit freely — the bodies are native, editable solids.

1. To AI-edit an existing design: export STEP from Shapr3D, then ask the AI

to inspect_model / modify_model it.

Generated files live in models/ (override with SHAPR3D_MCP_WORKDIR).

Development

uv run pytest

The suite exercises the modeling tools directly (no MCP transport, no Shapr3D app needed) in a throwaway workspace.

Limitations

• .shapr files are a proprietary, undocumented format — they can't be read

or written directly. STEP is the interchange format.

• Parametric history doesn't survive the round-trip (a STEP file is the

final solid, not the feature tree). Shapr3D's direct-modeling tools work on imported solids regardless.

• In-app actions (sketching, export) happen via the user or OS-level

computer-use automation; there is no app API to drive.

License

[MIT](LICENSE)

Source & license

This open-source MCP server is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: Alfredoalv13
• Source: Alfredoalv13/shapr3d-mcp
• License: MIT

Install and usage instructions live in the source repository linked above.