That collaborative loop is what separates spec-driven development from just writing a really detailed prompt. A prompt is static. A spec evolves.
What this means for your workflow
If you are building with AI agents and you do not have a spec layer, start with one thing: generate a structured analysis of the codebase you are working on. Not a summary. A full inventory: modules, dependencies, API surface, data models. Then give your agent that document as context before you ask it to build anything else.
You will notice the difference immediately. The agent stops asking clarifying questions. The output aligns with the real architecture instead of inventing its own. And when the agent does get something wrong, you can point to the spec and say "this is what we agreed on," which makes the correction precise instead of vague.
The spec is not extra work. It is the work that makes all the other work faster.