An improvement for one query group should not damage strong existing routes.

Golden queries

Test critical examples for each relevant release.

Exact matches

Check SKU, EAN and brand terms separately.

Relevance metrics

Compare the same judgments and query set with the baseline.

Zero-result searches

Make sure that the number of empty results does not grow unexpectedly.

Performance

Take query latency and index freshness with you as a guardrail.