RAG Interview Questions #6 - The Reformulation Trap
Why a one-size-fits-all query cleaner quietly shreds multi-hop questions into noise, and the adaptive upstream classifier you actually need to diagnose query shape.
You’re in a Senior ML Engineer interview at Anthropic and the interviewer asks:
“Your RAG system passes the raw user query straight to the retriever. Recall looks fine in your evals, but it collapses on real traffic, ambiguous and multi-hop questions especially. Before you touch the retriever, what does your query layer actually need to decide?”
Don’t say:
