Made myself a custom Codex pet today (you'll never guess what it was), and had some fun reverse-engineering how the fea…
By Simon Willison · Developer Tools
Made myself a custom Codex pet today (you'll never guess what it was), and had some fun reverse-engineering how the feature works - it generates animated sprite sheets using gpt-image-2 simonwillison.net/2026/Jul/14/...