Fable 5 costs 10 dollars per million input tokens against 5 for Opus 4.8, output is 50 vs 25
SWE-Bench Pro gap is 11.1 points, and FrontierCode more than doubles at 29.3 vs 13.4
Same API surface with one new 400: explicit thinking disabled rejects on Fable 5, omit the field
Cache minimum drops to 2048 tokens on Fable 5 while Opus 4.8 needs 4096 to...