Add a reranker so RAG stops burying the right chunk

My RAG system retrieves twenty chunks and stuffs all of them into the prompt, and the model gets lost in the noise.

IntermediateRead 5 minDoing: an hour or two, once you already have a batch of retrieved candidates and a way to call a reranker6 steps

▶ Start

What you'll have at the end

A reranked top 5 list where the chunk that actually answers your question sits in position one, replacing a plain vector-search ranking that buried it third.

Before you start

You need

A RAG pipeline whose vector search already retrieves a batch of candidate chunks for a question, before anything gets built into a prompt.

Not covered

Changing how the first-stage vector search itself finds candidates, only what happens to the list it already returns.

Leans on

6 steps

Where to go next

RAG's vector search misses exact terms that hybrid search catches

when the miss is an exact term vector search can't see at all, not a chunk that's merely ranked low

Your RAG's retrieval hit rate has never been measured

to check this fix holds across your whole question set with a real measured score, beyond the few you spot-checked here

Checked 15 Aug 2026

Part of the RAG (Retrieval Augmented Generation) cookbook