Start here. This is the direct spoken answer to practice first.
Why this question matters
Design and debug rate limiting while protecting the API without blocking legitimate users and integrations. It matters in real backend work because the team needs observability, ownership, and rollback room to recover without guessing. The practical angle is abuse protection, client fairness, rollout safety, distributed enforcement, and operational behavior, tied to a concrete production decision.
This follow-up starts after a rate-limit policy has been designed. I observe real request rates and cost by client and endpoint, identify legitimate bursts and batch workloads, and run the proposed rules in report-only or generous mode first. The rollout dashboard shows which known clients would receive 429, how often, and whether retry guidance is usable before enforcement can break them.