I had a task where I needed to automate some importing and simple cleanup of some PDFs into (hold your breath) AutoCAD files. It has been years since I have done any LISP and even then I wasn’t great. “Golly gee,” I thought. “Wouldn’t it be swell if I could have Claude do it for me?”
A quick search showed the Autodesk official Civil 3D MCP, that could be used on DWGs, of course, but the functionality looked limited and leaned heavily to Civil 3D elements. I found a straight up AutoCAD MCP… but you had to pay for it.
Well, I know a guy that made his own Revit MCP. Leaning on that structure, it took about 30 minutes to have a working AutoCAD MCP.
That Waybacklog Continued
I made sure that ports being used in ACAD and Revit were different, so they wouldn’t step on each other’s toes, and this would allow me to run one Claude chat that could look at both applications.
This would come in very handy.
Another item on the “We get to it when we get to it” to-do list is converting old details. You’ve heard the song, “I have so many amazing details in AutoCAD… that’s why I import!” or “That’s why I can’t use Revit!”
And redoing those details takes time.
If you have some good clean DWGs, Dynamo could certainly help out, but ultimately I would want the linework redrawn, not converted. And that is exactly what we were able to do.
I was given a handful of details that needed to get into Revit. I didn’t want to import and clean up, I wanted nice clean Revit details.
I opened the DWGs up in ACAD, and I opened Revit with our template and started an empty Drafting View. I didn’t tell Claude to start redrawing… I asked Claude how it could get the details from ACAD to Revit. I guess it knew my hatred for DWG imports, because that was never on the table. But no imports, no copy/paste (not sure how that would work) it just examined the coordinates of the geometry and started drawing.
Garbage In / Garbage Out
Two things I should have done at the start, which would have trimmed a good 20 minutes off this task.
First off, I had a typo and told Claude the typical faceplate was 1 3/4″ wide. Scaling from that, every line was wrong. And C did have to scale. The original DWGs were drawn… I don’t know, man. But the faceplates were 11 feet long. So it did the math to shrink it all down to actual size.
The second thing I should have anticipated was lineweights. I asked Claude to take its best guess based on what it was drawing, partly to see if it recognized what the detail was and partly to see what kind of graphic decisions it would make. Honestly, it did an OK job, but there were some oddities. And since this was the magical upside-down AutoCAD universe WHERE COLOR EQUALS THICKNESS I ended up just letting Claude know yellow was Line 5 and red was Line 3, etc. I could have looked at the DWGs more closely and started out sharing that info.
Get Drafting
But this again, opens a whole new pathway to getting the tedious tasks done and more importantly very very consistent. At this point a lot of the old ACAD detail catalogs have already been redone… but I now will be excited when we find some that haven’t.
