Cross-encoders as a precision stage: cheap recall first, expensive relevance second.
Skip to solutionKEEP THE
mediumAI Engineering
What is reranking and why add it after retrieval?
443 views
01
Understand the problem
rerankingcross-encoderretrievalrag
02
Attempt it yourself
Sketch your approach before reading the solution — that's what interviews test.
Nudge consolestandby
Stuck? Beam a request up — the console returns a conceptual nudge that guides your logic without spoiling the implementation.
03
Study the solution
A reranker is a cross-encoder model that scores each (query, document) pair jointly — far more accurate than comparing precomputed embeddings, but too slow to run over the whole corpus. So RAG pipelines do two stages: fast ANN/hybrid retrieval pulls top-50/100 candidates (recall), then the reranker reorders them and yo
Solution ready — 2 min read
Classified // press E to declassify
04
Read the code
Two-stage retrieval with a score floor
const candidates = await hybridSearch(query, { limit: 80 });
const scored = await reranker.rank({
query,
documents: candidates.map((c) => c.text),
topN: 8,
});
const kept = scored.filter((r) => r.relevance > 0.35); // calibrated floor
if (kept.length === 0) return abstain(); // no junk context
return kept.map((r) => candidates[r.index]);05
Join the discussion
Discussion (0)
Sign in to join the discussion.
No responses yet. Be the first to share what you think.
Transmission complete // awaiting log
KEEP THE
STREAK ALIVE.
Dossier 44 of 80 decoded in the AI Engineering track. One more won't hurt.