Of AI Coding Agents Context Management "Lost in the middle" despite 200K+ token windows Multi-File Coordination No real-time dependency graphs, missed instructions Silent Failures Removes safety checks, generates fake data silently Architecture Decisions Sees structure but doesn't understand trade-offs Enterprise Context Missing implicit business logic and unwritten rules
to TDD and BDD SDD What & Why Intent Level Human writes intent BDD System Behavior Feature Level Given / When / Then TDD Code Correctness Unit Level Red / Green / Refactor
Implementation 250k Developers in 3 Months AWS Kiro - The New Stack 94% Satisfaction Score Delta Airlines (re:Invent) 16k+ Spec Kit Stars in Week 1 GitHub (Sept 2025) Specs are the new code. 80-90% of our work as programmers is structured communication Sean Grove, OpenAI Sources: AWS Kiro, AWS re:invent (2025), The New Code – AI Engineer (2025)
Greenfield Projects Spec becomes single source of truth Complex Features Agents need structure to avoid breaking contracts Multi-Agent Coordination Specs prevent conflicting implementations Compliance & Audit Specs as traceable control surfaces Rule of thumb: If it takes 2+ prompts to explain, write a spec.
When NOT to Use SDD Small Bug Fixes Spec overhead exceeds the change Rapid Prototyping Uncertain requirements — specs need clarity UI-Heavy / Creative Work Visual design needs iteration, not specs One-Off Scripts Throwaway code — just vibe code it Rule of thumb: If you can explain the task in one sentence, skip the spec.