Claude Fable 5 and Claude Mythos 5
Anthropic
Claude Fable 5 is a powerful, new state-of-the-art AI model launched alongside the specialized, restricted-access Mythos 5 variant for cybersecurity and research.Summary
The article introduces Claude Fable 5, a high-performance, Mythos-class AI model capable of state-of-the-art results in software engineering, vision, and scientific research. Due to safety concerns, Fable 5 includes conservative safeguards that trigger a fallback to the Claude Opus 4.8 model for sensitive cybersecurity or biological queries. Simultaneously, the company is launching Claude Mythos 5 for authorized cyberdefenders and life science researchers, offering full capabilities without these specific restrictions. Both models are available via API with a focus on responsible deployment through a trusted access program and enhanced data retention policies.
(Source：Anthropic)