CAiD MCP Server

An MCP server that gives AI agents validated 3D CAD modeling via CAiD and OCP (OpenCASCADE). No GUI needed — the modeling engine IS the server.

Every geometry operation is validated through CAiD's ForgeResult system, which tracks volume, surface area, and diagnostics. If a boolean silently fails (common with OCCT), the validation layer catches it and tells you why.

You: "Make a box with rounded edges and a hole through the top, show me a preview"
Claude → create_box → fillet_solid_edges → add_hole → preview_object → export_stl
Result: SVG preview + ~/cadquery-output/my_part.stl

Available Tools (54 across 13 categories)

Use discover_tools() to browse, or discover_tools(category="query") for a specific category.

Project Structure

caid-mcp/
├── server.py                    # Entry point
├── caid_mcp/
│   ├── __init__.py
│   ├── core.py                  # Scene state, shared utilities
│   ├── types.py                 # Pydantic result models (v0.6.0+)
│   └── tools/
│       ├── primitives.py        # Shape creation (7 tools)
│       ├── modify.py            # Holes, fillets, chamfers, shell (4 tools)
│       ├── transforms.py        # Translate, rotate, scale, mirror (4 tools)
│       ├── booleans.py          # Union, cut, intersect, combine (4 tools)
│       ├── query.py             # Geometry inspection and measurement (6 tools)
│       ├── view.py              # Section and exploded views (2 tools)
│       ├── scene.py             # Workspace management (5 tools)
│       ├── export.py            # STL, STEP, SVG preview (5 tools)
│       ├── heal.py              # Validation and repair (3 tools)
│       ├── io.py                # BREP/STEP import-export (3 tools)
│       ├── assembly.py          # Multi-part assemblies (5 tools)
│       ├── compound.py          # Belt/pulley systems (3 tools)
│       └── advanced.py          # Scripting, patterns, tool router (3 tools)
├── examples/
│   ├── quickstart.py               # Install verification script
│   ├── GALLERY.md                   # Example gallery with prompts
│   └── images/                      # Rendered example images
├── tests/
│   └── test_cadquery_mcp.py
├── pyproject.toml
├── LLM_GUIDE.md                 # LLM-specific usage guide
├── CHANGELOG.md
└── LICENSE

Setup

Prerequisites

• Python 3.11+

Install

# 1. Create a virtual environment
python -m venv .venv
source .venv/bin/activate   # macOS/Linux
# .venv\Scripts\activate    # Windows

# 2. Install CAiD (brings in OCP and all dependencies)
pip install caid

# 3. Clone and install this server
git clone https://github.com/dreliq9/caid-mcp.git
cd caid-mcp
pip install -e ".[dev]"

Verify

source .venv/bin/activate
python -c "import caid; import mcp; print('All dependencies OK')"
pytest tests/ -v

Connect to Claude Code

claude mcp add-json caid '{"type":"stdio","command":"/FU

... [View full README on GitHub](https://github.com/dreliq9/caid-mcp#readme)