Say hello to text-to-cad, an open source tool for generating 3D models in Codex! Prompt and edit complex 3D models. Export STEP, STL, GLB, DXF and URDF files. Built for CAD newbies. Link to github below. CAD is hard. As a software engineer getting back into robotics, I’ve been... humbled by new tools like Onshape. Struggling to kick old habits, I started prompting Codex to generate 3D models and had some limited succes. After a few iterations I found a recipe that actually works: 1. Generate a python script for every STEP file. The agent can easily edit each part’s source without touching the raw STEP file. Use build123d > cadquery. 2. Reference specific faces and edges in prompts for precise edits. I built a basic local ui to inspect / cache STEP B-reps to make this easier. 3. Maintain markdown explaining important part features in plain English so the model can index on project context quickly. 4. Verify results with screenshots and geometry. Models don’t have great spatial awareness, but they can interpret images and verify constraints very well. For the best results I’ve been using GPT 5.4 xhigh / Opus 4.6+. Fair warning, this will burn through tokens, I recommend the Pro/Max plans if you’re planning on building anything serious. PRs welcome!show more

nice, we can help add joint to have more 4D effects,

PRs welcome! Here’s the repo:

will do

I think you’ll find if you make more complex things with more than a few knobs to turn with this the model will just shit out

I've got it managing a reasonably complex project at the moment, the secret sauce is in the reference system that helps me guide the agent to look at specific parts of STEP file topology, and ignore the rest

@curtisfloras can u explain a little further , how do you set up your codex agents. the workflow ?

@curtisfloras Yep! All you have to do is ask Codex or Claude Code to clone this repo into your project, then you’re good to go. The agent will read the AGENTS/SKILL files which tell it how to generate 3D models. Nothing fancy or opinionated.

너무 멋진데? 이런걸 공유해줘서 너무 고마워!!! 한 번 써볼께!!!👍

MIT now we takin

I am building my own autonomous system and CAD has been my biggest pain point. I will be over the moon if this works!

I was working on something like this a couple days ago! Nice.

sweet! I’ll give it a try tonight

Nice! I’m trying to connect freecad through mcp to an llm, but till now had been a huge pain…

@amypretzel

🔥🔥🔥

@MechPete scope this

Wow looks awesome Jake!

Cool work! I’ve also been also exploring Text-to-CAD and some Python libraries recently, but I’ve encountered a real-world feedback from enterprises: what they need is the 2D CAD engineering drawings acutally, with detailed dimensioning (including tolerances), chamfers/fillets,

Why build123d instead of CadQuery?

never a lack of software engineers building baby CAD software

Very cool! Curious how come build123d > cadquery?

build123d has good state management and leans into modern Python standards that the models have lots of training data on!

@zachdive

Nice

PRs welcome, let's see

wow this is really cool

then you can easily annotate any of these step files in your browser and send a link to your factory, without the hassle of making engineering drawings using OnyxCAD

I puked 3 times while watching this

@earthtojake This is cool! Can it produce x-wing drone bodies? OnShape is awful. It can’t produce rounded edges. They look like huge steps. No smooth gradient for wing angles running into drone body. Would this potentially be able to create that? I attached one for context.

Bruh you can use it with Claude code too why just codex lol

Going to test with claude soon, just been loving codex this month