Onshape MCP Server

Enhanced Model Context Protocol (MCP) server for programmatic CAD modeling with Onshape.

Features

This MCP server provides comprehensive programmatic access to Onshape's REST API, enabling:

Core Capabilities (45 tools)

• Document Discovery - Search and list projects, find Part Studios, navigate workspaces
• Parametric Sketches - Rectangles, circles, lines, and arcs on standard planes
• Feature Management - Extrude, revolve, thicken, fillet, chamfer, boolean, and pattern features
• Assembly Management - Create assemblies, add instances, position parts, create mates (fastened, slider, revolute, cylindrical)
• Assembly Analysis - Interference checking, position verification, face coordinate systems, body details
• Variable Tables - Read and write Onshape variable tables for parametric designs
• FeatureScript - Evaluate FeatureScript expressions, get bounding boxes
• Export - Export Part Studios and Assemblies to STL, STEP, PARASOLID, GLTF, OBJ
• Part Studio Management - Create and manage Part Studios programmatically

Installation

Prerequisites

• Python 3.10 or higher
• Onshape account with API access
• Onshape API keys (access key and secret key)

Setup

1. Clone the repository:

git clone https://github.com/hedless/onshape-mcp.git
cd onshape-mcp

2. Create a virtual environment:

python -m venv venv
source venv/bin/activate  # On Windows: venv\Scripts\activate

3. Install dependencies:

pip install -e .

4. Set up environment variables:

export ONSHAPE_ACCESS_KEY="your_access_key"
export ONSHAPE_SECRET_KEY="your_secret_key"

Or create a .env file:

ONSHAPE_ACCESS_KEY=your_access_key
ONSHAPE_SECRET_KEY=your_secret_key

Getting Onshape API Keys

1. Go to Onshape Developer Portal
2. Sign in with your Onshape account
3. Create a new API key
4. Copy the Access Key and Secret Key

Usage

Running the Server

onshape-mcp

Or directly with Python:

python -m onshape_mcp.server

Configuring with Claude Code

Add to your ~/.claude/mcp.json:

{
  "mcpServers": {
    "onshape": {
      "command": "/absolute/path/to/onshape-mcp/venv/bin/python",
      "args": ["-m", "onshape_mcp.server"],
      "env": {
        "ONSHAPE_ACCESS_KEY": "your_access_key_here",
        "ONSHAPE_SECRET_KEY": "your_secret_key_here"
      }
    }
  }
}

Important Notes:

• Use the absolute path to your virtual environment's Python executable
• Find your path: cd onshape-mcp && pwd to get the directory path
• On Windows: Use C:/path/to/onshape-mcp/venv/Scripts/python.exe
• Replace the API keys with your actual keys from Onshape Developer Portal
• Restart Claude Code after editing mcp.json

Verify it works: Ask Claude Code: "Can you list my Onshape documents?"

For complete setup instructions, see docs/QUICK_START.md.

Available Tools

Document & Navigation Tools

Tool	Description
list_documents	List documents with filtering and sorting
search_documents	Search documents by name or description
get_document	Get detailed document information
get_document_summary	Get comprehensive summary with workspaces and elements
find_part_studios	Find Part Studios with optional name filtering
get_elements	Get all elements (Part Studios, Assemblies, BOMs) in a workspace
get_parts	Get all parts from a Part Studio
create_document	Create a new Onshape document
create_part_studio	Create a new Part Studio in a document

Assembly Tools

Tool	Description
create_assembly	Create a new Assembly in a document
add_assembly_instance	Add a part or sub-assembly instance to an assembly
get_assembly	Get assembly structure with instances and occurr

... View full README on GitHub