Anthropic's Claude Fable 5 costs twice as much for 5.7 percent more performance

In three linesClaude Fable 5 scores 64.9 points on the Artificial Analysis Intelligence Index and sets records on 5 of 10 benchmarks. Performance gain over Opus 4.8 is only 5.7% while token costs double. Safety filters with fallback routing further increase expenses.

Summary generated by Claude — human-verified