For the last five weeks, Anthropic's $5 model was beating its $10 model. Today they fixed it. Fable 5 launched June 9 at $10 per million input tokens and $50 per million output. It was the new top tier, above Opus. Then Opus 5 came out July 24 at $5 and $25. Half the price. And it scored higher than Fable 5 on five of the seven benchmarks Anthropic published today. Coding, knowledge work, computer use, business workflows, science. Fable 5 only won on two, by less than a point and a half. So…

Claude@claudeaiSep 1

We’re introducing Claude Fable 5.1 and Claude Mythos 5.1. They're the world’s most advanced models for coding and knowledge work.