Asked about Fixing the query, not just the ranking
How do you decide which query techniques to keep?
An answer that works
Build a small labelled set: twenty or so real turns from a chat log with the chunks that answer them. Measure recall@k and MRR for each technique added one at a time, and record the extra model calls and latency beside them. Keep the ones that move a number you care about. On most chat corpora the standalone rewrite moves recall a long way and the rest move it very little, and you cannot tell which case you are in without the measurement.
Reading an answer is not being able to give one. The section that teaches this is Fixing the query, not just the ranking, 4 hours of Reranking & hybrid search.
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