Anthropic launches Claude Fable 5.1 and says it’s up to 45 percent cheaper for agentic work

Anthropic has released Claude Fable 5.1 and Mythos 5.1, addressing customer concerns about pricing, data retention, and overzealous safeguards. Fable 5.1 outperforms its predecessor while costing approximately 25% less typically and up to 45% less for complex agentic workloads due to cheaper cached data pricing. Early testers praise its coding abilities, natural language, and nuanced understanding. The model features refined safeguards that reduce false refusals on basic biology queries, though Mythos 5.1 retains previous restrictions. Anthropic also introduced Enterprise Frontier Safeguards for data privacy, storing data on customer servers, rolling out this fall. Fable 5.1 can now identify software vulnerabilities, but certain cybersecurity tasks remain restricted to Opus models. Fable 5.1 is widely available, while Mythos 5.1 is limited to Project Glasswing participants.

(Source：The Verge)