Anthropic launched Claude Fable 5.1 and Mythos 5.1, claiming Fable 5.1 costs up to 45 percent less for agentic tasks than Fable 5. The release addresses customer criticism of price, data retention, and safeguards. Every CEO Dan Shipper and Box CEO Aaron Levie praised performance, while Lisan al Gaib noted Mythos 5.1 at low reasoning matches its predecessor at Max reasoning. Fable 5.1 is available on all platforms; Mythos 5.1 only in Project Glasswing.
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