topic Re: AI + GDL in GDL

AI + GDL

Patrick M — Tue, 22 Sep 2026 22:17:17 GMT

I spent way too much time trying to teach chatbots, like chatgpt and gemini, the gdl help manuals/cookbook/etc... every script they threw at me was total garbage.
It turns out the 'full version' of claude is actually really useful for generating scripts, and even includes help guides for setting up parameter lists and trouble shooting bad script!

I threw a complex light fixutre together with a cut sheet, manuf. image, and a basic parameter:
"I need a light fixture from the attached cut sheet and image. It needs hotspots for each arm's angle and length. It needs a parameter for pendant length from the ceiling and a hotspot at the mounting point. max polygon count should be 15,000"

I didn't even need to request a 2d symbol, but I have no doubt it would edit the symbol to be whatever I need it to be given a few revised prompts.

I definitely recommend claude for GDL assistance!

object attached, for anyone curious.

Operating system used: Mac Apple Silicon

Re: AI + GDL

Patrick M — Tue, 22 Sep 2026 22:18:32 GMT

oh, and the object it fed me the script for was only 6,000 poly. If I 'morf barfed' this, it would have been easily 20,000 poly, and would have been static, except the hang height! this is a game changer for me!

Re: AI + GDL

Karl Ottenstein — Thu, 24 Sep 2026 00:54:48 GMT

Awesome!! Just an incredible result, Patrick. Thanks for sharing this and the hours that went into your experiments!

I think Apple gave a hint of who they thought had the best coding assistance in the new XCode which has both agentic and chat coding. Any additional agents or chat providers can be added, but Apple's defaults are Claude Sonnet/Opus and ChatGPT for chat, and Claude Agent, Codex (OpenAI) and Antigravity (Google) for agents.

Re: AI + GDL

David Collins — Wed, 23 Sep 2026 10:17:54 GMT

This is both amazing and terrifying in equal parts.

I was thinking these AI generated objects would all be in binary, but its GDL and the script is clear and concise. It would be easy to go in and tweak anything that needed an adjustment. (or I suppose, just tell Claude to do it).

So many questions:

Are the comments and notations in the script also coming from Claude? He’s actually explaining what he’s done ?

Did he also decide what parameters would be needed?

Was this done in one pass or were there many permutations needed to finish the object?

Thanks for sharing this.

Re: AI + GDL

CosminF — Thu, 24 Sep 2026 15:20:36 GMT

Great idea @Patrick M !

I tried this too with the paid version of Chagpt (by stealing your prompt and image) and it gave me the gsm file directly after one iteration:

It first gave me some instructions on how to copy and paste the scripts and where but then the second time round it just gave me the gsm file.

Neat stuff.

edit so I don't post-spam.
it can make guitars too:

Re: AI + GDL

Patrick M — Wed, 23 Sep 2026 20:16:36 GMT

thats awesome! I didnt ask claude to just give me the .gsm... it seems a little limited in which formats it can take/produce...

it works great for polygon reduction, but only accepts obj
it works great for polyline simplification (surveys), but only accepts DXF

Re: AI + GDL

Patrick M — Wed, 23 Sep 2026 20:20:49 GMT

Hey David!
it did indeed write all comments and gave parameter lists, names, and default values!

this was one pass. I copy/pasted the scripts in (master script, 3d, 2d, and parameter). I had about a dozen errors found in the script. 4 were due to a parameter typo on my part. 5-6 were due to a parameter matrix error, also on my part. the few script errors it fed me, it found and replaced when I gave it the error message and line found on.

...

it became very obvious that I could have fed it any number of revisions; for a custom symbol, symbol text, additional surface break downs, etc.

...

I had been trying for years to get chatGPT to learn GDL. I swear I lost half my hair in that attempt. This was so night and day by comparison!

Re: AI + GDL

Chris Grantham — Wed, 23 Sep 2026 20:26:33 GMT

When you say full version, did you use Opus 5.5 or Fable 5.1?

Re: AI + GDL

Patrick M — Wed, 23 Sep 2026 20:29:39 GMT

I honestly don't know... its the 2.7032.0 desktop app

Re: AI + GDL

Laszlo Nagy — Thu, 24 Sep 2026 15:26:26 GMT

This is also what I wanted to ask: Is this done in the Claude desktop app? Or in the Claade Code part of the app?

And which model are you using? If you go back to the conversation where you asked Claude to create it, you can see it in the bottom right corner. Is it Opus? Sonnet? Fable? And which version? 5.0? 5.1? 5.5? etc. Also, which Effort level? Low, Medium, High, Extra? Max? Different models at different effort levels cost different amount of tokens. It would be good to know if you can achieve these results with less expensive models and effort level or you need to use the best with Max effort.

Re: AI + GDL

Miles Smith — Thu, 24 Sep 2026 16:20:12 GMT

Personally, I really like your file naming convention for this.

Re: AI + GDL

Patrick M — Thu, 24 Sep 2026 17:19:19 GMT

a bit tongue in cheek... as this took almost 0 GDL skills at all (it helped to know the terminology, like: paramater, value, array...)

Re: AI + GDL

Patrick M — Thu, 24 Sep 2026 17:20:27 GMT

it is the desktop app, but I've been told the browser interface may have some advantages. Opus 5.5 medium

Re: AI + GDL

Laszlo Nagy — Thu, 24 Sep 2026 19:13:00 GMT

Thanks. That is pretty good if a non-top-of-the-line model with Middle effort can create such useful GDL library parts. I will need to test it myself. The future looks bright for custom content creation in Archicad.

Re: AI + GDL

Ricardo Heim — Fri, 25 Sep 2026 12:47:11 GMT

Just adding up to the conversation, I'm now starting to mess with the LLM to code some GDL also and I found useful to creata a config file where you give the AI the context of who you are, what are you trying to accomplish and a set o skills to guide it to do all the things needed for a GDL script using less tokens. I'm using the deepseek 4.1 flash API with the deepseek harness as it is most cost effective here in Brazil and I'm getting good results. I told the AI to do all the configuration, creating the config file, the skills...

Re: AI + GDL

Keny90 — Sat, 26 Sep 2026 23:19:09 GMT

AI has advanced tremendously in recent months. I use the Claude desktop application—specifically the "Claude Code" window—running the Opus 5 (now version 5.5) model at the "High" setting. It is connected to Archicad via an MCP connector, allowing it to code in GDL with incredible efficiency. As a side note, it’s brilliant not just at GDL but also at model checking and construction—though GDL is the focus here.
Up until now, I’ve mostly given it existing elements that needed modification or repair. I simply copy the relevant .gsm file over, tell it what I want, and it handles the rest: converting it to .xml, doing the work, converting it back to .gsm, and then notifying me to refresh the library. I don’t have to copy and paste code manually.
I’ve been writing GDL objects for over 20 years; while I’m not a professional developer, I can certainly hold my own. There were a few objects I had abandoned in the past because I’d reached the limits of my expertise. I set the AI to work on some of these elements, and it successfully finished and fixed them. Honestly, I was blown away by how flawlessly it codes. Here are a few examples of what it has done:
I needed a piece of furniture quickly, so I assembled it from slabs and saved it; later, I gave it to the AI to turn into a parametric version. I converted an office chair from Rhino; the result was an ugly object with a massive polygon count and visible edges. In this case, too, it worked with the .gsm file, as the original .obj or .3ds files were no longer available. It optimized the polygon count and removed unnecessary edges.
What really amazed me was when I gave it a standard single-leaf door from the basic ArchiCAD library and asked it to make one of the divided door panels parametric—allowing the height and thickness of the divider to be adjusted. For those unfamiliar with the subject: I consider doors and windows to be among the most complex elements, involving over a thousand parameters and nested macros. To my great surprise, it only messed up a minor detail in the user interface; apart from that, it executed the task flawlessly.
The next step is to have it create a completely new element with complex functionality based on a written description.

Re: AI + GDL

claudiuiancic — Sun, 27 Sep 2026 19:30:16 GMT

I created a Claude Code skill and have achieved surprisingly good results so far. You might want to test or use it yourselves. You can find it here:
https://github.com/claudiuiancic/gdl-skill

Re: AI + GDL

vtomaz — Mon, 28 Sep 2026 07:24:53 GMT

Great. Thank you!

Re: AI + GDL

fabioverissimoTUU — Sat, 03 Oct 2026 17:49:46 GMT

Hi friends,

I went deep on this stuff this afternoon.

I gave Claude the GDL pdf from GS and the manufacture catalog of a Ringlock Scaffolding that i needed. After a few prompts it gave me the XML to make the GSM.

After that, I went deeper and asked for the separated parts.

In the end I've asked for a simplified Ringlock Scaffolding that I could hide parts as I wish. He made me an amazing array to do what i wanted.

This is a game changer for our work.

I'm yet to try the Claude Code skill.

than you all, it's inspiring to see your posts,

Fábio

Re: AI + GDL

PB — Fri, 02 Oct 2026 18:57:26 GMT

Simply amazing.

Many thanks for sharing