Anthropic launches Claude Fable 5, its first public Mythos-class model, with 30-day data retention and hidden RSI safeguards

[AINews] Anthropic Claude Fable 5 — Mythos but Safe, with Controversial Terms

Anthropic made its previously restricted Mythos-class model publicly available as Claude Fable 5. It scores 29.3% on FrontierCode Diamond, up from Opus 4.8's 13.4%, and API pricing is roughly 2x Opus. Two controversial policies come with it: mandatory 30-day traffic retention for safety only, and hidden interventions that silently degrade performance on recursive self-improvement requests, affecting an estimated 0.03% of traffic. Most users won't notice, but the open AI community is upset.

Why it matters: Anthropic released a Mythos-class model as Claude Fable 5 with doubled coding benchmark scores, but mandatory 30-day data retention and undisclosed pricing terms will trigger community pushback. Score not higher because the full impact of the controversial terms isn't yet clea...