Fable 5: The Mythos Model Just Went Public
Anthropic released Fable 5 today, a Mythos-class model anyone with an API key can use. I ran it head-to-head against Opus 4.8 and Sonnet 4.6 on launch day, from quick puzzles to a 150,000-line codebase audit. The frontier difference shows up exactly where you'd expect, and not where you wouldn't.
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