In my experience the MCP is not needed, it just runs headless FreeCAD using CLI. The MCP can be useful if you want to run FreeCAD on a VPS, and then use ChatGPT e.g. on your phone (optionally via voice). But for local I'd go with the CLI. But they'll do just fine with the MCP, which probably wraps the Python API anyway (ideally, otherwise it could lack some features).