Blog · Inventor · 1 Oct 2026 · 5 min read

How to drive Autodesk Inventor from the terminal without an MCP server

There is no official Inventor MCP server, and you do not need one. An AI agent can drive Inventor 2025 over COM from the command line. The method that works, the three that do not, the error codes you will see, and the rules that keep a batch run from breaking.

Short answer: attach to the Inventor that is already open with GetObject, from a VBScript run with cscript. That gives an AI agent working in a terminal, such as Claude Code, the whole Inventor API: open files, create drawings, read geometry, export DXF and PDF. No MCP server, no add-in, no plugin.

Everything below was tested on Inventor 2025 on Windows 11, during months of batch work on hundreds of steel parts.

The method that works

1. Open Inventor yourself and leave it open. The script attaches to it, it does not start it.
2. Write the script as a .vbs file.
3. Attach with GetObject, and stop with a clear message if Inventor is not running.
4. Run it with cscript //nologo script.vbs from the terminal. The agent reads the output and decides the next step.

' attach.vbs - run with: cscript //nologo attach.vbs
Dim oApp
On Error Resume Next
Set oApp = GetObject(, "Inventor.Application")
If Err.Number <> 0 Then
    WScript.Echo "ERROR: Inventor is not running (err " & Err.Number & ": " & Err.Description & ")"
    WScript.Quit 3
End If
On Error Goto 0

oApp.SilentOperation = True          ' no dialogs during Open/Add
WScript.Echo "Attached. Open documents: " & oApp.Documents.Count

SilentOperation = True before Documents.Open or Documents.Add stops the dialogs that would otherwise freeze the script waiting for a click nobody will make.

The three methods that do not work

Rule: GetObject first, CreateObject only as a fallback. Never close or hide an instance you attached to: it is the user's.

When VBScript is not enough: compiled C

Some API methods return arrays by reference: SurfaceEvaluator.GetNormal, Evaluator2D.GetParamExtents, Matrix.AsArray. VBScript cannot call them. We tried every route:

The agent writes a small C# program and compiles it with the csc.exe that ships with .NET Framework:

csc.exe /target:exe /platform:x64 /out:Probe.exe ^
        /reference:"C:\Program Files\Autodesk\Inventor 2025\Bin\Autodesk.Inventor.Interop.dll" Probe.cs

Four traps:

• Copy the Interop DLL next to the .exe, or it fails at run time with FileNotFoundException.
• The .NET Framework csc.exe is an old compiler: no tuples.
• Inventor.File clashes with System.IO.File. Qualify one of them.
• Run csc.exe from PowerShell, not Git Bash. Git Bash turns /nologo into a file path.

Errors you will meet, and what they mean

Do and don't

Do

• Attach with GetObject from cscript.
• Set SilentOperation = True before opening or creating documents.
• Close what you open, in every exit path.
• Copy a style before you change it. Built-in styles are shared by other annotations.
• Leave documents with unsaved changes alone. They belong to the user: close without saving.
• Read API signatures from the Interop DLL by reflection. Enum values written from memory were wrong.

Don't

• Don't start a second Inventor.
• Don't edit title block definitions by script. It corrupted a template.
• Don't use Dim inside a For Each in VBScript: it fails on the second pass.
• Don't use CInt for counts or IDs: it overflows at 32767. Use CLng.
• Don't trust "no error". AddTitleBlock with prompt strings returned success and left every field empty.

Questions people ask

Is there an official Inventor MCP server? Not as of October 2026. Autodesk has an official MCP server for Revit and one for its product help pages, which only reads documentation. For Inventor there are community projects, and they wrap the same COM API shown here. You can use that API directly: the terminal is the interface.

Can Python drive Inventor? Python can call COM, but we do not use it for that. We use VBScript and compiled C# for Inventor, and Python for reading the DXF and PDF files Inventor produces.

Does Inventor have to be open? Yes. The script attaches to the running application.

Can it run iLogic rules from outside? Not directly. That needs a bridge: how to run an iLogic rule from outside Inventor.

How do you know a run worked? By opening what it produced. A script that ends without errors has not proved anything. See Inventor API errors and what they mean.