Measuring relevance with the eval CLI
Grade your own search against a golden set of queries, so a change to ranking is measured, not just eyeballed.
suo eval runs a set of judged queries against your index and reports standard relevance metrics, the same way suo's own engine is graded in CI before a ranking change ships.
Writing a golden set
A golden set is a list of queries with graded expected results, 0 (irrelevant) to 3 (exactly right):
Anything not listed for a query is treated as ungraded and excluded from that query's score, not counted as irrelevant — so a golden set does not need to judge every record, only the ones that matter for that query.
Running it
Metrics
Comparing before and after a change
Run suo eval before and after a settings change — a new synonym, a custom ranking rule, a searchable tier reweighted — and compare the two reports directly. This is the same discipline the engine team uses internally: a paired comparison against the previous run, not a single number in isolation.
CI
Add suo eval --set golden-sets/docs.json --index docs --fail-under ndcg=0.75 to your CI pipeline to catch a regression in relevance before it reaches production, the same way a test suite catches a regression in code.