Design an AI Agent Token Rate Limiter

Published 3 October 2026

Onsite Round 2 — AI Agent Token Rate Limiter

The system design round asked me to design a rate limiter for AI agents whose usage was measured in billing tokens rather than simply request count.

The design needed to control how quickly an agent could consume tokens while still allowing reasonable bursts. The discussion centered on a token-bucket-style model and how token consumption should be enforced in a production system.