Spec-Driven Development: Why Prompting is a Dead End

Let's be honest: the "Prompt Engineering" honeymoon is over. We've all had that moment where we ask an LLM to build a feature, it gives us a beautiful piece of code that looks correct, and then two hours later we're drowning in a sea of subtle bugs and schema mismatches.

The problem isn't that the AI is "stupid." It's that we're asking it to guess our intentions instead of giving it a blueprint. At ASCA, we call this the Hallucination Ceiling. It's the point where vibe coding fails because the system complexity exceeds the model's ability to track hidden constraints across a large context window.