From what I can tell after some preliminary testing, you have to pass an additional large language model to the OpenAI API when generating SVGs.

I couldn't find this requirement in the documentation, but if you don't pass one in, you get this error:

  400 {"message": "SVG generation requires 'svg.model'.",
     "param": "svg.model", "code": "missing_required_parameter"}

I tried it with Sunburst with both gpt-5.5 and gpt-5.6-sol, and the results were nothing spectacular. It’s something you could already do in the ChatGPT interface by asking it to convert an existing image to an equivalent SVG.

https://imgpb.com/bkUrc

Recraft is probably the only group I know of that had a native text-to-SVG generator pretty early on, but since it’s a closed model, I’m not familiar with what they were doing under the hood technically.

https://fal.ai/models/fal-ai/recraft/v4/pro/text-to-vector