Simon Willison’s Weblog
Introducing GPT-6 Astra for developers ( via ) Blink and you'll miss it, but there's a familiar creature at 1m59s :
Across the board, Astra has more attention to detail, better understanding of the user's prompt, and can build more sophisticated outputs. In particular, it excels at building 3D models. I've seen it make incredible renderings of gardens, shipyards, animals , cityscapes, even Dyson spheres.
Astra really does believe in putting a red neckerchief on a pelican riding a bicycle.
Recent articles
The Pelican comparison grid for Astra is pretty interesting - 4th September 2026
OpenAI's rogue agents were caught communicating via public wikis - 4th September 2026
Claude's new system prompt really doesn't want to reproduce song lyrics - 2nd September 2026
This is a link post by Simon Willison, posted on 5th September 2026 .
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