Anthropic releases Fable 5.1 with lower cache-read pricing

Anthropic introduced Claude Fable 5.1, which it says is generally available, alongside the more restricted Claude Mythos 5.1. Anthropic says Fable 5.1 will cost an estimated 25% less than Fable 5 for typical token-billed workloads because of lower cache-read pricing; it estimates savings of up to about 45% for highly agentic work. The company says enterprise safeguards will roll out in phases beginning later this fall, while eligible customers can use zero data retention in the interim.