Claude Fable 5.1 and Claude Mythos 5.1 launched

Anthropic@claudeaiSep 1, 2026

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. https://t.co/8P9PSrWPi3

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Launched Sep 1, 2026View post
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#3 Launch This Week on Launch Archive

Claude Fable 5.1 and Claude Mythos 5.1 launched ranked #3 this week.

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