verification

End-to-end verification traces the flow from the UI trigger through the client request, API route handler, external dependencies, and back to the rendered response. Each boundary is checked with evidence such as screenshots, console output, and server logs, stopping at the first broken boundary.

Start by inferring the feature's data flow, then gather evidence at each layer: browser console, dev server terminal, runtime logs, and environment variables. Common breaks include missing awaits, wrong HTTP methods, and env vars absent at runtime.

Yes, it triggers on dev server commands including next dev, vite, astro dev, vercel dev, and package manager variants like pnpm dev and bun run dev. The verification approach applies to any framework with routes, API endpoints, and data sources.

It catches missing await on async operations, HTTP method mismatches between client and handler, environment variables present in .env.local but absent at runtime, server modules imported in client components, and type mismatches between API responses and client expectations.

Use flow verification when a feature partially works or behaves unexpectedly across layers, since unit tests only cover isolated logic. It is designed for integration-level issues spanning browser, API, and data boundaries, not for replacing jest or vitest suites.