Anthropic released Claude Sonnet 5 on Tuesday, positioning the model as a budget-friendly alternative to its flagship Opus line just as the AI lab barrels toward a long-anticipated initial public offering. The company is calling Sonnet 5 its “most agentic Sonnet model yet,” capable of building plans, operating browsers and terminals, and running autonomously at…
Claude Fable 5 and Claude Mythos 5 are, by Anthropic’s own description, the same underlying model. One is available to anybody with a Claude subscription or API key. The other is restricted to a vetted group of cybersecurity firms, critical infrastructure providers, and selected biology researchers. For the first time, a frontier AI lab has…