SolidWorks MCP Server

Control SolidWorks with plain language. This Model Context Protocol server connects AI clients such as Claude and Codex to SolidWorks, so you can describe a part — "a 60mm mounting bracket with four M5 clearance holes and 3mm fillets" — and watch it get built, feature by feature, in a real SolidWorks session.

This is, as far as I can tell, the most complete MCP server for SolidWorks available, and I will be expanding as time allows.

The connected AI client gets a broad tool set covering sketching, solid features, assemblies with mates, configurations, equations, neutral-format import/export, and — critically — feedback: it can query faces and edges, check mass properties, detect interference, and take labeled screenshots of the model to see what it's actually building.

What it can do

• Full sketching — lines, arcs, splines, slots, polygons, text, whole chained profiles in one call, plus driving dimensions and geometric constraints
• Solid features — extrude, revolve, sweep, loft, boundary; the matching cuts; fillet, chamfer, shell, draft, rib, wrap; linear/circular patterns and mirror
• Assemblies — insert saved parts, position them with mates (coincident, concentric, distance, angle, gears...), check interference
• Parametrics — named configurations, per-configuration dimensions, and equations that re-solve when driving dimensions change
• Model awareness — Claude can enumerate faces/edges with exact coordinates, find a face by description ("the angled face"), read mass properties against any coordinate system, and look at labeled screenshots of the model mid-build
• Import and export — open STEP / IGES / Parasolid / ACIS / STL files, optionally running feature recognition to rebuild a parametric tree from an imported solid; export to the same formats by giving save_document a neutral extension
• A readable design tree — read the timeline as structured data, rename features and sketches to say what they're for, and group them into folders, so the model a human opens is one they can follow
• State tracking — every feature, sketch, and entity gets a stable ID, scoped per document, so multi-part + assembly sessions stay coherent

What it can't do

• Taste - Claude does not replace design reviews, or having a sense for how things should be done.
• Interpreting drawings - Most AI Agents have a hard time interpreting complex or degraded drawings.

Requirements

• Windows (SolidWorks only runs on Windows)
• SolidWorks 2022 or later, installed and activated (tested on SolidWorks 2025)
• Claude Desktop, Codex, or the ChatGPT desktop app (other local MCP clients may also work with manual configuration)

That's it — the installer below takes care of Python and everything else.

Installation

Easy install (recommended)

Open PowerShell (press Win, type "PowerShell", press Enter) and paste:

powershell -ExecutionPolicy Bypass -c "irm https://raw.githubusercontent.com/HarrierPigeon/Solidworks-MCP-Server/main/scripts/install.ps1 | iex"

The script installs uv (which provides Python — you don't need Python installed), downloads the latest release, and sets up an isolated environment under %LOCALAPPDATA%\SolidWorksMCP. It auto-detects Claude Desktop and Codex/ChatGPT desktop and registers the server with each confidently detected client.

To choose explicitly, download the script and run one of:

.\install.ps1 -Client Claude
.\install.ps1 -Client Codex
.\install.ps1 -Client Both

Valid selections are Auto (the default), Claude, Codex, and Both. “Codex” covers the local Codex clients and ChatGPT desktop MCP configuration; it does not enable the hosted ChatGPT web app.

Then restart the configured client completely and ask it to "create a 50mm cube in SolidWorks".

To update later: re-run the same one-liner.

To uninstall: delete %LOCALAPPDATA%\SolidWorksMCP, remove the "solidworks" entry from %APPDATA%\Claude\claude_desktop_config.json if configured, and run codex mcp remove solidworks if configured for Codex.

Manual install (for developers)

Prerequisites (in addition to the requirements above):

• Python 3.10 or later — check "Add python.exe to PATH" during install
• Git (or download the repo as a ZIP from GitHub instead)

git clone https://github.com/HarrierPigeon/Solidworks-MCP-Server.git
cd Solidworks-MCP-Server
pip install -r requirements.txt

(Or pip install -e . for an editable package install.)

Tip: clone somewhere that isn't a network drive.

For Claude Desktop, register the server in %APPDATA%\Claude\claude_desktop_config.json (Claude Desktop → Settings → Developer → Edit Config):

{
  "mcpServers": {
    "solidworks": {
      "command": "python",
      "args": ["C:\\path\\to\\Solidworks-MCP-Server\\server.py"]
    }
  }
}

For Codex and ChatGPT desktop, register it with:

codex mcp add solidworks -- python C:\path\to\Solidworks-MCP-Server\server.py

Restart the configured client and you're set. (Microsoft Store installs of Claude Desktop keep its config under %LOCALAPPDATA%\Packages\Claude...\LocalCache\Roaming\Claude instead.)

Try it

The die below was modeled entirely by Claude from this single prompt — and its correctness is checkable: opposite faces sum to 7, and the volume reported by mass properties matches the analytic value for a filleted cube minus 21 pips to five significant figures.

Make a simple dice: 16mm cube, 2mm fillets on all edges, then put the correct
pip pattern (1 through 6) on each face using shallow 2.5mm-diameter cut
circles. Opposite faces must sum to 7. Show me screenshots of three different
views when done so I can check your work.

More prompts to get a feel for it:

Create a 100mm cube in SolidWorks.

Make a bracket: 80x50x6mm base plate with a 40mm tall vertical wall along one
long edge, 5mm fillets where they meet, and four 6mm through-holes in the base.

Model a simple bolt: M10-ish — 10mm shank, 30mm long, hex head. Then show me
an isometric screenshot.

Build a two-part assembly: a plate with a 20mm hole and a 20mm pin, saved as
separate parts, then mate the pin concentric into the hole.

Claude works best when you give real dimensions, but it will make sensible choices if you don't. It can also read what it built (get_faces, get_mass_properties, look_at_model) and fix its own mistakes.

The tools

Every tool is prefixed solidworks_ (e.g. solidworks_sketch_circle). Dimensions are millimeters, angles are degrees — conversion to the COM API's meters/radians happens internally.

How it works

Claude  →  MCP tool call  →  server.py dispatch  →  solidworks/ module  →  SolidWorks COM API

• The server connects to a running SolidWorks instance (or launches one) via COM (pywin32).
• Every created object gets a stable ID (feat:Boss-Extrude1, sketch:Sketch1, comp:bracket-1) tracked per document, so Claude can refer back to things it built — even across multiple parts and an assembly in one session.
• Tools return structured JSON, and geometry-query tools return coordinates that can be fed directly into selection-based tools (fillet this edge, sketch on that face).

Troubleshooting

Claude says it can't connect to SolidWorks

• Make sure SolidWorks is installed and activated; launching SolidWorks before Claude Desktop is the most reliable order.
• If SolidWorks runs elevated, run Claude Desktop as Administrator too (COM won't cross the elevation boundary).

The server doesn't show up in Claude Desktop

• Restart Claude Desktop fully: File → Exit (not just closing the window), then reopen.
• Check the config file for JSON typos: %APPDATA%\Claude\claude_desktop_config.json (Microsoft Store installs: %LOCALAPPDATA%\Packages\Claude...\LocalCache\Roaming\Claude\).

"No Part template found"

• Templates are auto-discovered at C:\ProgramData\SOLIDWORKS\SOLIDWORKS <year>\templates\. If yours live elsewhere, adjust the glob in solidworks/connection.py.

Hole Wizard hangs or errors

• hole_wizard can trigger a blocking SolidWorks dialog on some setups. The reliable fallback is a sketched circle + cut-extrude, which Claude will use if you ask.

Anything else

• Check solidworks_mcp.log next to server.py (easy install: %LOCALAPPDATA%\SolidWorksMCP\app\), then open an issue with the relevant lines.

Development

python test.py            # full test suite (needs a live SolidWorks)
python test.py --list     # list tests; --category / --test / --gui to filter
python dev_server.py      # hot-reload dev server (pip install watchdog)
python clean.py           # close all open SolidWorks documents

There is no mock of the COM layer — tests drive a real SolidWorks instance. tests/agent_capability_tests.md additionally contains 46 copy-paste prompts for end-to-end testing through Claude itself. Architecture notes live in CLAUDE.md.

Contributions welcome — please open an issue or PR.

Known limitations

• Drawing (2D drafting) generation isn't implemented yet.
• hole_wizard may trigger a blocking dialog (see Troubleshooting).
• Design-tree folders are flat, and a folder's membership has to be decided when you create it: SolidWorks rejects MoveToFolder for moving features into an existing folder, and folders can't be nested. create_feature_folder with the full feature list is the path that works.
• recognize_features recovers a partial tree. On real mechanical parts it typically reconstructs holes, fillets and chamfers around a structural core it can't decompose, leaving the remainder in an Imported<n> body — so treat it as a head start, not a full parametric rebuild. It also needs SOLIDWORKS Professional or Premium.
• WIDTH mates aren't implemented; component positioning is mate-driven (direct transform setting isn't available via late-bound COM).
• no PDM / PDM Pro or 3DExperience (Enovia) awareness. If you have extra PDM Pro licenses, or access to the Enovia API docs, please reach out!

License

MIT

Disclaimer: This project is not affiliated with or endorsed by Dassault Systèmes SolidWorks Corporation. "SolidWorks" is a registered trademark of Dassault Systèmes. Generated geometry should be reviewed before usage. May cause happiness or induce wonder. If your session lasts longer than 3 hours consider drinking water and adjusting your chair.