Is every rerank useful?
Compare always reranking with a conditional decision that uses first-stage retrieval signals.
02INDEPENDENT UNDERGRADUATE RESEARCH
Ask carefully.
Measure honestly.
My research investigates when retrieval systems can do less work while staying within a quality tolerance fixed before the experiment.
RETRIEVAL / 2026
ToolRet
When does reranking earn its cost?
A learned router chooses when to run an expensive cross-encoder over a 37,292-tool catalog. Development, calibration, and confirmation are separated by relevant-tool components.
Independent undergraduate work at Cornell Engineering. This is an empirical study, not a peer-reviewed publication.
UNTOUCHED CONFIRMATION23.4%
fewer cross-encoder calls
CROSS-ENCODER CALLS · 1,500 QUERIES
Always rerank1,500
Conditional router1,149
351 fewer calls on untouched confirmation queries.
Predeclared tolerance: 0.01 nDCG@10 loss. Quality superiority was not established.
Freeze before confirmation.
Separate relevant-tool components across development, calibration, and 1,500 untouched confirmation queries.
Keep the result inspectable.
Retain configurations, random controls, the report, and an independent audit in the public repository.