When RAG Systems Fail: Catching Edge Cases Before Production

RAG systems often break not on typical queries but on edge cases—empty retrievals, conflicting documents, out-of-scope questions, and adversarial inputs. Testing these failure modes is critical for production reliability, as most users will exploit untested edge cases rather than follow the intended happy path. This guide covers five essential edge case tests that distinguish robust RAG systems from those destined to hallucinate and mislead in real-world deployment.