Spec-Driven Development: What AWS's Kiro Got Right

AWS introduced Kiro in July, and the notable thing was not that it writes code — everything does now. It was the insistence on producing a specification and a design before implementation.

Why that ordering matters

The failure mode of agentic coding is not bad code. It is confidently building the wrong thing quickly, then generating tests that confirm the wrong thing works. Forcing an explicit requirements step puts a human checkpoint exactly where the cost of being wrong is lowest.

Where it fits

Well-defined features with clear acceptance criteria benefit enormously. Exploratory work, where the point is to discover the shape of the problem, benefits less — a specification you cannot yet write is not a useful gate.

We use the pattern rather than any single tool: write the spec, get it agreed, then let the agent implement against it. It maps neatly onto how client engagements already run.