Anthropic's new mid-tier model Claude Sonnet 5 arrives as Fable and Mythos sit boxed up under a U.S. export order.

Claude Sonnet 5 is the most agentic Sonnet model yet, rivaling Opus 4.8 in performance at lower prices, Anthropic said.

Claude Sonnet 5 brings near-Opus 4.8 agentic performance at a mid-tier price, from $2/$10 per million tokens until August 31. Here's what is new.