Originally published on AI Tech Connect.
What you need to know One provider is a single point of failure. Every provider returns 429s, 5xx errors and timeouts, deprecates models and has regional outages. If your product calls one API directly, your uptime is capped by theirs. A gateway fixes this structurally. Put a proxy in front of OpenAI, Anthropic, Google and your own self-hosted vLLM, expose one OpenAI-compatible API, and you get failover, load-balancing, central key management, budget caps and observability in one place. Three layers of resilience. Retry the same model with backoff; fall back to the next model in a chain; and circuit-break a model into cooldown when it keeps failing — all driven by a clear error taxonomy. Resilience costs latency. Fallbacks add roughly 200 to 500 ms to p95 because retries are serial. Cap…
