Claude's strongest Fable 5.1 released! Eight benchmark top rankings, up to 45% price reduction, anti-distillation mechanism launchedClaude最强Fable 5.1发布！8项屠榜，最高降价45%，反蒸馏机制上线
Anthropic released Fable 5.1 and Mythos 5.1.
Model update
Fable 5.1 achieves first place on eight public benchmarks and reduces cache read pricing by up to 75%.
The update also introduces an anti-distillation mechanism that prevents manual editing of context in multi-turn dialogues while preserving chain-of-thought records.