Anthropic rolls out Claude Fable 5, but it's available for a limited time

Anthropic has begun rolling out Fable 5, a guarded version of its powerful Mythos-class model that includes strict safeguards to block sensitive queries (e.g., offensive cybersecurity, biology, chemistry). The article explains Fable 5's limited availability to vetted partners, its high compute/token consumption (noting rapid exhaustion in testing), and the company's rationale for restricting broader access due to potential misuse, but it does not report an actual cyber incident or active exploitation.