How I AI · Tuesday, September 22, 2026
Anthropic's Opus 55 is the first Opus-level model to incorporate Fable-level cyber and bio guardrails, aiming for increased safety. While it can help users fix their own bugs, it will prevent or downgrade certain security and bio-related tasks.
“Opus 55 is the first Opus level model that has shipped with the Fable level kind of like cyber and bio guard rails”
“and so you should be able to fix your own bugs in um in Opus 55 but you won't be able to do cyber security work or bio work like make choices it'll kick you down to Opus 48 or block you”
“Anthropic is saying that this is its most aligned model”