Anthropic brings Mythos to the masses with Claude Fable 5, its most powerful generally available model ever
Summary
Anthropic today launched two new AI models: Claude Fable 5 and Claude Mythos 5. Fable 5, the version for most users and developers, surpasses all previous generally available Claude models with stronger performance in software engineering, knowledge work, vision, scientific research, and long-running tasks. Mythos 5 is a restricted upgrade for approved users, including cybersecurity partners and select biology researchers. Fable 5 wraps Mythos-class capabilities in new safeguards, routing high-risk requests to Claude Opus 4.8. Over 95% of Fable sessions run on its own responses, with no universal jailbreaks found after 1,000+ hours of testing. Fable 5 is available to the public today; Mythos 5 initially only to existing restricted users.
Why it matters
Anthropic makes its most powerful AI model capabilities broadly available to the public for the first time, marking a key balance between frontier AI safety and accessibility.
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