Anthropic loosens Fable 5's biology restrictions but keeps the guardrails on for virology and toxicology

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Anthropic has cut false positives in its biology safety filters for Fable 5 by about 85 percent.

Previously, nearly all biology-related queries got blocked and rerouted to the less capable Opus 5.

The restrictions stay in place for sensitive dual-use topics like virology and toxicology.


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