Fable 5 is WAY better than Opus 5. It is not even close.
Opus 5 is slow and it is lazy. It stops early, skips steps, and tells you it is done when it is not.
I now launch three subagents on tasks Fable 5 one shots. That is my actual workflow.
I called Opus 5 the best model in the world two weeks ago. I was wrong.
Anthropic dropped it on a Friday out of nowhere. That said everything.
Fable 5.1 is the one I am waiting for.