Spec-driven development is when you take these AI generated design docs and make it all you as a dev interact with. It's waterfall but make it stupid and AI.
You give AI some guidelines and a feature description, then you twiddle your thumbs while it generates giant specs and occasionally asks you for some inputs, then you attempt to read the thing, give up, and give it to some other agent. Rinse and repeat until you burn a GDP of a small country in tokens and the agents agree that it's going to work, and then you finally pull the lever and hopefully a feature matching all your specs appears. Or it doesn't! And if it didn't, it's surely your fault because you didn't give AI enough context.
I'm tired, boss.