3D CAD Converter MCP server

Lets an AI agent (Claude Code, Claude Desktop/Cowork, Codex, Cursor, VS Code and other MCP clients) use 3D CAD Converter on your Windows PC: converting STEP, IGES, STL, OBJ, FBX, glTF, 3MF and other 3D/CAD files.

3D CAD Converter is a Windows 10/11 desktop app with a free trial: https://www.contenta-software.com/3dcadconverter/download.php

How it works

This package is a small launcher. It finds 3D CAD Converter on your PC (cadconvert.exe, installed per-user in %LOCALAPPDATA%\Programs\CadConverter or on your PATH) and runs the app's own MCP server (cadconvert serve) over stdio. Tools: convert_cad, detect_format, get_file_info, list_formats.

If the app is not installed yet, the launcher serves a single get_started tool that gives your agent the download link and the install steps instead.

Add it to your client

Claude Code (Windows):

claude mcp add cad-converter -- cmd /c npx -y @contentasoft/[email protected]

Claude Desktop, Cursor and other clients that use mcpServers (JSON):

{
  "mcpServers": {
    "cad-converter": { "command": "cmd", "args": ["/c", "npx", "-y", "@contentasoft/[email protected]"] }
  }
}

VS Code (.vscode/mcp.json, note the servers key):

{
  "servers": {
    "cad-converter": { "type": "stdio", "command": "cmd", "args": ["/c", "npx", "-y", "@contentasoft/[email protected]"] }
  }
}

Codex (codex mcp add cad-converter -- cmd /c npx -y @contentasoft/[email protected], or ~/.codex/config.toml):

[mcp_servers.cad-converter]
command = "cmd"
args = ["/c", "npx", "-y", "@contentasoft/[email protected]"]
startup_timeout_sec = 60
tool_timeout_sec = 3600

The first start downloads this small package, which can take longer than a client's default startup timeout (Codex: 10 s; Claude Code: set MCP_TIMEOUT); after that it starts at once. Long jobs such as video encodes can exceed a client's default tool timeout too (Codex: 60 s; Claude Code: MCP_TOOL_TIMEOUT). The app is told to stop a job when the client cancels it.

Once the app is installed you can also skip the launcher: "command": "cadconvert", "args": ["serve"].

What runs and what is sent

• The launcher itself sends nothing over the network and writes nothing to disk. It starts cadconvert.exe.
• The app works on local files on your PC. It sends anonymous usage telemetry (which tools ran, which MCP client connected, trial state) to ContentaSoft; turn it off in the app's settings. Privacy policy: https://www.contenta-software.com/3dcadconverter/privacy.php
• The free trial gives 10 conversions at full quality within 30 days of the first launch; after that STEP/IGES/BREP are meshed at draft quality and every export carries a trial note. Nothing is blocked. Nothing stops working; a licence removes the limits.

License

The launcher is MIT-licensed (see LICENSE). 3D CAD Converter itself is commercial software by ContentaSoft AB.