Simon Willison’s Weblog
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Recent articles
Claude Opus 5.5, GPT-6 Sol, GPT-6 Luna, and a new price war - 22nd September 2026
Jev introduces a new shape of LLM - System One, aka Decision Models - 21st September 2026
Generating running routes with GPT-6 Astra and ChatGPT Work - 12th September 2026
This is a beat by Simon Willison, posted on 23rd September 2026 .
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