Spec-First AI Coding: Making LLMs Build What You Actually Want
Spec-first AI coding replaces vague prompts and chaotic code generation with a simple workflow: clarify requirements, write a spec, then let the AI implement exactly what you approved.
The biggest failure mode in AI-assisted development is letting the model decide what to build. Spec-first coding flips the dynamic: you decide what to build, and the AI decides how to build it.
Instead of tossing a vague prompt at an LLM and hoping for the best, you introduce a lightweight but powerful step: a shared specification that both you and the AI treat as the source of truth.
The Vibe Coding Trap
Most developers using AI tools today follow this pattern: