Anthropic Apologizes to the invisible Claude Fable Guardrail

Korean Alpha EN (@korean_alpha_en), Jun 13, 2026, 00:52 UTC

Anthropic Apologizes to the invisible Claude Fable Guardrail - The Claude Fable 5 is the first widely available model in the Mythos family of Anthropic and has applied hidden restrictions to prevent distillation attempts used to develop competitive systems - Anthropic has decided to withdraw the existing method of changing and downgrading the response without informing the user of the request determined as distillation, and to be more transparent when restricted - In the new method, distillation-related requests are switched to Claude Opus 4.8 instead of Claude Fable, which users can see when…

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