FreeCAD MCP server: let Claude design 3D models in FreeCAD

• Adds a new shape or part to a FreeCAD document

  Creates a new object, such as a box, cylinder or sketch-based feature, in an open document and can send back a screenshot of the result.

  Try: “Add a 40 x 20 x 10 mm box to my bracket document”

  Write · create_object

• Changes the size, position or other settings of a part

  Updates the properties of an existing object, like its dimensions or placement, and can return a screenshot so you can see the change.

  Try: “Make the mounting holes 5 mm wide instead of 4”

  Write · edit_object

• Takes a screenshot of the 3D view from a chosen angle

  Captures the current FreeCAD view as an image, from angles like front, top or isometric, so the assistant can check what it built.

  Try: “Show me the part from the top”

  Read · get_view

• Lists every object in a document with its settings

  Returns all objects in a document with their properties, so the assistant knows what is already in the model.

  Try: “What parts are in the gearbox document?”

  Read · get_objects

• Shows the details of one object

  Returns the properties of a single object in a document, such as its size and position.

  Try: “What are the dimensions of the lid?”

  Read · get_object

• Lists the documents open in FreeCAD

  Returns the names of all documents currently open in FreeCAD.

  Try: “Which FreeCAD files do I have open?”

  Read · list_documents

• Starts a new, empty FreeCAD document

  Creates a new document in FreeCAD to build a model in.

  Try: “Start a new document called phone-stand”

  Write · create_document

• Runs Python code inside FreeCAD to build or change a model

  Runs any Python script inside the FreeCAD window. This is how the assistant does most complex modelling, and it has the same access to your computer as you do.

  Try: “Write and run a script that makes a gear with 24 teeth”

  Runs code · execute_code

• Adds a ready-made part from the FreeCAD parts library

  Inserts a standard part, such as a screw or bearing, from the FreeCAD parts library into your document.

  Try: “Insert an M3 screw from the parts library”

  Write · insert_part_from_library

• Lists the parts available in the FreeCAD parts library

  Returns the parts you can insert from the FreeCAD parts library.

  Try: “What fasteners are in the parts library?”

  Read · get_parts_list

• Runs a stress analysis and reports peak stress and movement

  Runs FreeCAD's CalculiX solver on an analysis you have set up and reports the maximum stress, the largest movement and the mesh size.

  Try: “Run the stress analysis on the cantilever and tell me the peak stress”

  Runs code · run_fem_analysis

• Removes an object from a document

  Deletes an object from an open document.

  Try: “Delete the test cube”

  Delete · delete_object

• Reopens a saved document to show changes made outside FreeCAD

  Closes and reopens a saved document so FreeCAD shows changes written to the file by a separate script.

  Try: “Reload the bracket document so I can see the new threads”

  Read · reload_document

• Runs heavy scripts in a separate FreeCAD process so a crash stays contained

  Runs a Python script in a separate, windowless FreeCAD process, useful for heavy geometry that might crash, and returns what it printed.

  Try: “Generate the threaded rod in a separate process so FreeCAD does not freeze”

  Runs code · execute_code_headless

• Starts a long calculation in the background

  Starts Python code running in the background and returns a job number, so long geometry work does not block FreeCAD.

  Try: “Compute the loft in the background and add it when it is done”

  Runs code · execute_code_async

• Used by the assistant behind the scenes

  Checks whether a background job finished or failed

  Reports whether a background job is still running, done or failed, with the error if it failed.

  Read · get_async_status

• Checks the connection to FreeCAD and the add-on version

  Reports whether the connection to the FreeCAD add-on is healthy, which add-on version is installed and whether it matches the server.

  Read · get_rpc_status

Watch out for

• It can run any Python code on your computer

  Its code tools run Python with your user's permissions, not only CAD actions. Read what the assistant plans to run and keep backups of important files. github.com

• Old add-on copies let web pages run code

  A web page open in your browser could send code to the add-on while its server was on, and the advisory names no fixed version. The add-on does not update itself, so copy in the current FreeCAD MCP folder and keep its server off when you are not using it. github.com

• Remote mode sends traffic unencrypted

  With remote connections on, there is no sign-in unless you set a token and nothing is encrypted. Use an SSH tunnel, or set a token and allow only the machines you need. github.com

• It can delete objects in your open files

  It edits and deletes objects in open documents directly. Save before long sessions so you can go back. github.com

• Turn off auto-start when you do not need it

  The add-on's server listens while it runs. Start it by hand when you need it and stop it afterwards. github.com

Security advisories

In their words