Fable won’t answer basic biology questions
The Verge·June 10, 2026
Anthropic has released Claude Fable 5, its most powerful AI model, which excels in various skills, including biology. However, Fable is intentionally designed to refrain from answering basic biology questions, instead redirecting queries to its predecessor, Claude Opus 4.8. This limitation is not due to Fable's lack of knowledge, but rather a deliberate design choice made by Anthropic. As a public-facing Mythos-class model, Fable's capabilities are restricted to prevent potential cybersecurity risks associated with its advanced abilities.
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