Why Vector Search Never Says "No Results"

Vector search systems are designed to always return nearest neighbors, even when user intent has no meaningful match in the corpus.

In production, this means "always returning something" can easily become "returning misleading results" unless confidence is explicitly modeled.

In our search platform, reliability improved when retrieval included confidence thresholds, keyword overlap checks, metadata validation, and score-gap heuristics.

The key engineering lesson is that retrieval quality is not only about finding relevant results; it is also about knowing when not to answer automatically.