An agent that runs tests locally and reports green is telling the truth — but only on its machine, where the .env, the local DB, and the cached node_modules exist. CI runs a clean checkout. The gap shows up in your pipeline.
Agents edit Dockerfiles and CI YAML like application code. They miss layer cache order, build-arg scoping, and the gap between your laptop and the runner.
Versioning is less about where the number goes than about knowing what actually breaks a client and communicating the sunset. Here is the honest tradeoff between path and header versioning, a breaking-change checklist, and how to enforce it with OpenAPI diffs in CI.
