Reranking
62%
Lesson 5 of 8

Reranking

Reranking takes retrieved candidates and scores them again with a stronger relevance signal.

Active reading
Why this matters

Reranking takes retrieved candidates and scores them again with a stronger relevance signal.

Retrieve

Get a broad candidate set.

Rerank

Score query–chunk relevance more carefully.

Trim

Keep only the best evidence.

Understand the working model

Vector similarity is fast and useful, but the nearest chunk is not always the most answerable chunk. A reranker can compare the query and each candidate more directly before context is assembled.

Reranking is especially useful when documents contain overlapping language, many similar sections or short chunks that share vocabulary but differ in meaning.

Example
Retrieve 20 candidates quickly → rerank all 20 → send the best 5 to the answer model.
Practice

Apply the pattern above to one real task you already do. Keep the first version small enough that you can inspect every input and output.

Common mistake

Do not add reranking before you can measure whether basic retrieval is actually failing.

Key takeaway

Use reranking when you need better ordering of a broad candidate set, then keep the final context small.

Next lesson

Grounded Answers

Continue to the next lesson.

Continue →