Demo of ChatGPT Code Interpreter running in o3-mini-high. OpenAI made GPT-4.5 available to Plus ($20/month) users today. I was a little disappointed with GPT-4.5 when I tried it through the API, but having access in the ChatGPT interface meant I could use it with existing tools such as Code Interpreter which made its strengths a whole lot more evident - that’s a transcript where I had it design and test its own version of the JSON Schema succinct DSL I published last week.
Riley Goodside then spotted that Code Interpreter has been quietly enabled for other models too, including the excellent o3-mini reasoning model. This means you can have o3-mini reason about code, write that code, test it, iterate on it and keep going until it gets something that works.

Code Interpreter remains my favorite implementation of the "coding agent" pattern, despite recieving very few upgrades in the two years after its initial release. Plugging much stronger models into it than the previous GPT-4o default makes it even more useful.
Nothing about this in the ChatGPT release notes yet, but I've tested it in the ChatGPT iOS app and mobile web app and it definitely works there.
Recent articles
- Distributing Go binaries like sqlite-scanner through PyPI using go-to-wheel - 4th February 2026
- Moltbook is the most interesting place on the internet right now - 30th January 2026
- Adding dynamic features to an aggressively cached website - 28th January 2026