Anthropic says Fable 5.2 and Mythos 5.2 are the same underlying model. Fable carries cyber and biology safeguards and is available to everyone as claude-fable-5-2; Mythos is open by application through Anthropic's verification programs.
In the News: November 9, 2026 (Extra 2)
Anthropic released Claude Fable 5.2 at a lower price than 5.1 and says 1,000 agents formalized Fermat's Last Theorem in 30 hours. The figures are Anthropic's own.
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