Edge Case Behavior

Edge case behavior is what happens when things get weird — when a user makes an unusual request, combines topics in unexpected ways, or pushes against the limits of what the model is intended to do. Models that perform beautifully on typical inputs often degrade unpredictably at the edges: they become overly cautious, give contradictory responses, or produce outputs that don’t match any reasonable interpretation of their intended behavior. For behavior architects, edge cases are both the most challenging and the most revealing part of model evaluation — they expose gaps in behavioral specifications, inconsistencies in training data, and assumptions that seemed reasonable until they weren’t. Edge case libraries, built up over time from real-world usage, are among the most valuable assets a behavior team can maintain.