What is query routing in a RAG/agent system, and how do you decide where a query should go?
Pushing every query through one pipeline wastes latency, money, and precision. A router decides what each query actually needs. The signal is naming the four decisions a router makes and how you stop a misroute from sinking the answer.
Updated Sep 2026 · Grounded in real GenAI, LLM, and AI/ML engineering interview loops and written to a senior-engineer editorial bar.
Pushing every query through one pipeline wastes latency, money, and precision. A router decides what each query actually needs. The signal is naming the four decisions a router makes and how you stop a misroute from sinking the answer.
Lead with where the obvious approach breaks, because that is the judgment they are screening for — most candidates jump straight to the happy path and lose the room.
Then walk the failure back through the pipeline in order, naming the one metric the customer's exec sponsor actually cares about before you propose the fix.