Claude Fable 5 can run for days. When does a solo dev actually want that?

Claude Fable 5 shipped this morning. The headline is that it runs for days on its own, sustaining long, asynchronous tasks earlier models couldn't. Reading the announcement, my first thought wasn't "impressive," it was "when would someone like me, a solo plugin developer, actually use this, and what happens to my bill if I do?" This post is that question. It isn't a feature tour, and it isn't a hands-on review. The model came out today and I haven't run it for days yet. It's the facts as announ...