Anthropic releases Claude Fable 5.2 and Mythos 5.2, citing gains in coding, science, and speed

Anthropic says Fable 5.2 and Mythos 5.2 are the same underlying model, with Fable carrying cybersecurity and biology safeguards for general availability while Mythos requires verification-program access. Outputs are up to 30% faster than 5.1, priced at $8/$40 per million tokens, with an optional 2.5x fast mode at $16/$80. In prerelease testing the models reportedly completed a Python-to-Rust migration, solved two open black-hole physics problems, and formalized Fermat's Last Theorem in 30 hours. Benchmarks place it above Opus 5.5 on most measures.

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