Solid Edge MCP Server

AI-assisted CAD through the Model Context Protocol. Create, analyze, modify, and export Solid Edge models from Claude or any MCP client.

119 tools · 53 resources + 2 guides · 4 prompts · Windows only (COM automation) · MIT

What it does

• Connect to a running Solid Edge, or start one
• Documents: create, open, save, close parts, sheet metal, assemblies, drafts
• Sketch 2D profiles: lines, circles, arcs, rectangles, polygons, splines, constraints
• Features: extrude, revolve, sweep, loft, helix, cutouts, holes, rounds, chamfers, patterns, ref planes, surfaces, sheet metal
• Assemblies: place components, relations, transforms, BOM, interference
• Drafts: drawing views, annotations, dimensions, parts lists
• Query: geometry, mass properties, feature tree, variables, materials
• Export: STEP, STL, IGES, JT, Parasolid, PDF, DXF, images

How much of it works

Every number here is measured, and reference/VERIFICATION_STATUS.md carries the commands that regenerate it.

• 164 of the 213 create_* backend methods verify their own result. The body’s face count and volume, or the COM collection the feature lands in, must change; otherwise the call reports an error instead of status: "created". A call that succeeds and builds nothing was this server’s defining bug, and it can no longer pass silently.
• The other 49 refuse before touching COM, returning unsupported: True with the evidence: a Solid Edge defect, a call that crashes the process, or an object only the UI can select. Each is listed with its evidence in the status document. The largest groups are swept and lofted surfaces, threads on an existing cylinder, ordered flanges and louvers, contour flanges, blends, wires, and assembly patterns and mirrors.
• Every tool has been driven against a real Solid Edge. scripts/live_sweep.py records the outcome of all 119 in reference/LIVE_SWEEP.md: 116 OK, 16 honest refusals and 2 deliberate error probes across 134 cases on Solid Edge 2026.
• 80 integration tests pin the fixes and a known-answer box; the unit tests cover shape, not truth.

Requirements

• Windows 10/11
• Solid Edge installed, licensed, and launched at least once (registers the COM server). Developed against Solid Edge 2025/2026.
• Python 3.11+ and uv

Install

git clone https://github.com/tylerwagler/SolidEdge-MCP
cd SolidEdge-MCP
uv sync --all-extras

Configure your client

Claude Code: copy examples/claude_code.mcp.json to .mcp.json in your project (or run claude mcp add solidedge -- uv --directory C:/path/to/SolidEdge-MCP run solidedge-mcp).

Claude Desktop: merge examples/claude_desktop_config.json into your claude_desktop_config.json.

Both examples use:

{
  "mcpServers": {
    "solidedge": {
      "command": "uv",
      "args": ["--directory", "C:/path/to/SolidEdge-MCP", "run", "solidedge-mcp"]
    }
  }
}

Restart the client, then ask it to connect to Solid Edge.

Environment variables

Troubleshooting

• Server does not start: run uv --directory C:/path/to/SolidEdge-MCP run solidedge-mcp in a terminal and read stderr.
• “Not connected”: call manage_connection(action="connect") first. If Solid Edge was restarted, call it again; the server drops the dead connection and reattaches.
• COM error 0x80070005 (E_ACCESSDENIED) on assembly pattern/mirror: those APIs are blocked for automation in Solid Edge 2025/2026. Pattern at part level instead.
• Feature “created” but nothing visible: the server verifies geometry after every material-changing feature and reports an error when nothing changed. Check the sketch is closed and on the plane you expect.

Conventions the LLM sees

The server publishes these in its MCP instructions and in two resources, solidedge://guide/workflows and solidedge://guide/conventions:

• Lengths in meters, angles in degrees
• Reference planes are 1-based: 1=Top (XY), 2=Right (YZ), 3=Front (XZ)
• Faces, edges, features, components are 0-based
• Every result is a dict; {"error": ...} means failure. COM failures carry hresult.
• Solids need a closed sketch: create_sketch → draw_* → close_sketch → create_extrude

Tools carry MCP annotations (readOnlyHint, destructiveHint) and tags (part, assembly, draft, sheet_metal, query, export, app, document, sketch, diagnostics) so clients can filter the manifest.

Architecture

src/solidedge_mcp/
├── server.py          # FastMCP instance: instructions, registration
├── managers.py        # Global backend manager instances
├── prompts/           # Server instructions, guides, prompt templates
├── tools/             # MCP surface: one module per area, register() each
│   ├── _registry.py   #   register_tool/register_resource: COM thread + annotations
│   ├── features/      #   50 feature tools split by family
│   ├── resources.py   #   53 read-only solidedge:// resources
│   └── guide.py       #   solidedge://guide/* resources
└── backends/          # pywin32 COM automation
    ├── connection.py  # attach/start Solid Edge, liveness + reconnect
    ├── com_thread.py  # single STA worker thread all COM calls run on
    ├── errors.py      # com_error -> readable error dicts
    ├── documents.py   # create/open/save; tracks document switches
    ├── sketching.py   # 2D profiles
    ├── features/      # 3D features (mixin package)
    ├── assembly/      # assembly operations (mixin package)
    ├── query/         # interrogation (mixin package)
    ├── export/        # export, drafting, views (mixin package)
    └── constants.py   # Solid Edge enum values

Every tool and resource is marshalled onto one COM worker thread (CoInitializeEx STA), because FastMCP otherwise runs synchronous tools on a thread pool and COM proxies are apartment-bound.

Development

uv sync --all-extras
uv run pytest              # unit tests (mocked COM); integration tests deselected
uv run pytest -m integration   # needs a running, licensed Solid Edge
uv run pytest --cov        # coverage
uv run ruff check . && uv run ruff format --check .
uv run mypy src/

CI runs lint, format, type check, and unit tests on windows-latest for pushes to master and every pull request. That is a weak gate: the COM audits skip when the gitignored type-library dump is absent, and no runner has Solid Edge, so the audits, pytest -m integration and scripts/live_sweep.py run only on a machine that does. Run them before tagging a release.

COM conformance

Unit tests mock COM with objects that answer to any attribute, so a misspelled member or a wrong argument count passes them and only fails against real Solid Edge. Six checks close that gap using the scraped type libraries, and four more need none:

uv run python scripts/audit_com_signatures.py --by-file
uv run python scripts/audit_com_signatures.py --filter backends/features/_holes.py
uv run python scripts/audit_com_receivers.py
uv run python scripts/audit_com_writes.py
uv run python scripts/audit_com_hasattr.py
uv run python scripts/audit_reported_writes.py
uv run python scripts/audit_com_enum_args.py
uv run python scripts/audit_dead_params.py

tests/unit/test_constants_typelib.py verifies every COM enum value in constants.py. tests/unit/test_com_members.py fails on any COM member name absent from the type libraries. tests/unit/test_com_receivers.py goes further: it infers what each receiver is by following declared types and fails when a member is read off an interface that does not have it, which is invisible to a name check when the name is real somewhere else. tests/unit/test_com_writes.py covers the other direction: a write to a member that is a method, or to a property the type library marks read-only. Solid Edge answers “Property ‘Item.X’ can not be set.” and a try/except around it turns the dead feature into a reported success. All skip when the dump is missing, so a fresh clone and CI stay green.

Four checks need no type library. tests/unit/test_reported_writes.py fails when a COM write is swallowed by a suppress and the value is then reported as applied – the shape behind most of the silent no-ops found in this codebase, from text heights that never changed to a variable rename that reported “not found”. tests/unit/test_com_hasattr.py fails on hasattr used to test what a COM proxy can do: the probe reads False both for a member that is absent and for one whose getter raised, which is how every layer call came to refuse draft documents, whose layers live on the sheet rather than the document. tests/unit/test_manager_mro.py fails when two mixins define the same method on a manager, which leaves one of them unreachable.

tests/unit/test_dead_params.py fails when a parameter is declared and never read, in a tool or a backend method. Nothing downstream can catch that: Solid Edge is never told the value, so it has nothing to reject, and the call returns a cheerful success. Three shipped that way – a component position that always placed at the origin, a table position Solid Edge chose for itself, and a revolve axis setting nothing consulted. A parameter that genuinely has nowhere to go says so with del .

scripts/scrape_typelibs.py regenerates reference/typelib_dump.json (gitignored, ~20 MB) from the installed Solid Edge type libraries. reference/typelib_summary.md is the committed digest. scripts/manual/ holds hand-run COM experiments; they are not tests.

License

MIT