Addressing the challenge of managing API consumption at scale, this blog post discusses the issue of exponential cool-down periods caused by 429 errors, which occur when API rate limits are exceeded. It explains that non-compliance with the "Retry-After" header and concurrent API consumption by multiple services can lead to increased back-off times, affecting service performance and Service Level Agreements (SLAs). The solution proposed is a "Consumer-side 429 Responder Proxy," which maintains a shared state of API traffic across all consuming services, ensuring that API calls are regulated according to a unified policy. This approach prevents exponential increases in cool-down times by simulating 429 responses when necessary, thereby optimizing API performance and maintaining SLA standards. The proxy ensures that cool-down periods remain minimal by managing API calls within defined limits, allowing for improved efficiency and reduced waiting times across services consuming the same API.