What Is Claude Mythos and Project Glasswing (Everything We Know)
Claude Mythos is Anthropic’s most powerful AI model ever built. Here’s everything we know about the leaked model, its capabilities, the Capybara codename, and when you can use it.
タグ: Mythos
Meet Claude Fable 5, Anthropic’s New Mythos-Class Model
On June 9, 2026, Anthropic released Claude Fable 5, the first model in a brand new top tier the company calls the Mythos class. Seven weeks later it still sits at number one on Arena’s text leaderboard, the largest human-preference board in AI, with 16,056 votes behind a 1507.6 rating. What changed since launch is the competition inside Anthropic’s own lineup. Claude Opus 5 arrived on July 24 at half the token price, and on most agentic and coding work it now matches or beats Fable 5. This article covers what Fable 5 is, how the Mythos class works, the full benchmark picture, the safeguard system, pricing, and the 18-day […]
