alt Hacker NewsThe Sonnet 5 comment is spot on. Even Anthropic's own graph initially showed lower performance at higher costs. Only thing I notice about Sonnet 5 is that it does appear to hand off tasks to agents more frequently similar to Fable, but of course nowhere near the quality of Fable. My guess is that Opus 5 will do similar but just isn't ready yet.
Sonnet 5 is a huge regression and many times it performs worst than deepseek. I believe Antrophic staff themself don't use Sonnet and use Fable for everything.