Opus 5.5: Fable's Level at 40% of the Price
Anthropic shipped Opus 5.5 on September 22: by its own numbers, Fable 5.1's level on most work, at $4/$20 per million tokens against Fable's $10/$50, with medium as the new default effort. What the release measures, where the catch is, and how my Claude seat left Fable the same afternoon.