Claude Fable 5.1 Just Found a Bug Four Years of Engineers Couldn’t
Anthropic released Claude Fable 5.1 and Claude Mythos 5.1 on September 1, with Fable 5.1 scoring 52.6% on Terminal-Bench-Science 0.1, up from Fable 5's 24.7%, and cutting cache read prices by 75% to $…