Anthropic launched Claude Fable 5, a new top public tier priced at $10 per million input tokens and $50 per million output tokens — roughly double Opus pricing. Alongside it came Claude Mythos 5, the same model without the safety classifier, restricted to vetted institutions.

The launch was rocky: US export controls briefly halted Fable 5 service from June 12 to June 30, and the pricing drew complaints from developers used to cheaper flagships. Anthropic bet that top-end capability justified a luxury tier.

Fable 5 split Anthropic's lineup in two — a premium Fable line and the mainstream numbered Opus line — a structure the company kept through the 5.1 refresh in September.