How AI Agents Verify Cross-Service Integrations: The 4-Step Verification Pattern

The Bug Code Review Often Misses Imagine implementing a feature perfectly — clean code, passing tests, approved PR. Now imagine that feature is completely unreachable because the service that was supposed to call it never did. No error. No failing test. Just silent, dead code sitting in production. This is the class of bug that lives at integration boundaries — between repositories, services, teams, async producers and consumers, or config layers. It's largely invisible to traditional code review because reviewers usually operate closer to the PR boundary than the architectural boundary. The failure often isn't obvious in any one file — it's in the missing link between pieces of code that each look correct in isolation. What I want to dig into here is a structured verification pattern I've found effective for AI-assisted audits of these gaps. You can apply the same logic manually or build tooling around it. Why Grep Isn't Enough (But You Still Need It) When auditing integration boundar