Anthropic: Fable 5.1 and Mythos 5.1 Are Identical
BLUECOW009 · x · 2026-09-02
The System Card confirms that Fable 5.1 and Mythos 5.1 are the exact same model, differing only in their safeguards.
Related event: Anthropic Confirms Fable 5.1 and Mythos 5.1 Share One Base Model(3 posts)→
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