OpenAI's Codex is the Best Way to Use ChatGPT: A PM's Guide

Here's how to get 10x more out of ChatGPT than your average PM

We had two major new model releases this week, Opus-4.6 and GPT-5.3-Codex. But the most important update in AI, for my money, was neither.

It was the Codex App. It’s the new, most powerful way to use ChatGPT.

And that’s why OpenAI hasn’t even released GPT-5.3-Codex in ChatGPT. It’s only available in Codex.

So that’s today’s deep dive.