Claude Fable 5.1 and Claude Mythos 5.1

Anthropic has released Claude Fable 5.1 and Claude Mythos 5.1, advanced AI models designed for coding, knowledge work, and scientific research, with Mythos 5.1 offering specialized safeguards for cybersecurity and life sciences work. The new models cost approximately 25% less than their predecessor for typical workloads (up to 45% less for complex agentic tasks) and include improved safeguards that reduce false positives by 60% in cybersecurity applications. Additionally, Anthropic is introducing Enterprise Frontier Safeguards for data privacy, allowing customers to store data on their own infrastructure rather than Anthropic's servers.