Anthropic announced the release of its new Claude Fable 5.1 and Claude Mythos 5.1 models on September 1, referring to them as “the world’s most advanced models for coding and knowledge work.”

In June, Anthropic first released Fable 5, its Mythos-class AI model for Claude. Three months later, Anthropic is enhancing Claude...

Anthropic releases Claude Fable 5.1 broadly and Mythos 5.1 to vetted Project Glasswing users, with 1M token context and reduced cache costs.