hjbaard/SolidWorks-MCP

Let an AI agent (Claude, or any other MCP client) model real parametric parts and
assemblies in your own SolidWorks — and check its own work. Every
modelling call returns the measured volume, mass and bounding box, so the agent
can compare the result with the spec and correct itself instead of guessing that
it "looks about right".
Built by the tools themselves: a mounting bracket (every step checked against a hand calculation), an M10 bolt with a real thread, a revolved + shelled vase, a swept pipe, a lofted + shelled horn.
## Why this server
It verifies, not just generates. Features report measured geometry;
dimensions and mates are measured back after the rebuild.
Fully defined sketches. Every sketch is constrained the way a designer
would: dimensions from the origin, relations only where the geometry is
exactly horizontal, vertical or on the origin. Tools return their dimensions
by role (width@Sketch1), so the part stays editable, in SolidWorks or
through the agent.
Real CAD, not just primitives. Extrude, revolve, sweep, loft and splines;
holes, counterbores, slots and pockets on any face; rounded polygon corners; ISO holes from the Hole Wizard; real ISO metric threads;
fillets, chamfers, shells, patterns, mirrors, ribs, equations and materials. Assemblies
with mates and interference checks. STEP/STL/3MF export and screenshots.
Engraved and embossed text. Work on existing parts: list, delete, suppress and reorder features; read, extrude and cut a person's sketches; import STEP. Colours per part or component. Joints with concentric and angle mates, checked over their range. Printability checks and dimensioned drawings. Planes at any offset or angle. Several bodies per part, combined and split. Variable fillets and full rounds. Free sketches with tangent arcs and splines. 86 tools in total.
It fails loud. A call that cannot do what was asked returns
{ok: false, error} with the cause, never silently wrong geometry.
A fixed, typed tool surface. There is no "run arbitrary code" tool; the
agent can only do what the tools allow.
Tested against real SolidWorks. 691 tests; each feature's integration test
compares the result with a hand calculation.
Local. It talks to your running SolidWorks over COM; the server itself
makes no network calls.
## Quickstart
1. Install uv.
2. Start SolidWorks and leave it open (the server attaches to the running
instance — it does not launch one).
3. Register the server with your MCP client.
Claude Code:
bash
claude mcp add solidworks -- uvx solidworks-mcp
Claude Desktop (claudedesktopconfig.json) or any other client:
json
"mcpServers": {
"solidworks": {
"command": "uvx",
"args": ["solidworks-mcp"]
It is also listed in the official
MCP Registry
as io.github.hjbaard/solidworks-mcp.
4. Ask for a part, for example:
> Design a 100 × 80 × 8 mm mounting plate with a Ø16 mm centre bore, four
> counterbored M5 holes 12 mm from the corners and R5 corners. Check the
> volume against your own calculation, then export a fine STL.
## Guidelines for agents
The server hands every MCP client short modelling guidelines when it connects
(conventions, verify each step, known pitfalls). The full guide is the resource