A Tiny First-Call Checklist Before Trusting Any LLM Gateway

I usually do not trust a new LLM gateway from the pricing page alone. My first test is intentionally small and boring. Here is the checklist I use before sending real traffic: Create a fresh API key. Run one tiny chat request. Confirm the requested model is visible in the logs. Confirm the served/provider model is also visible. Check input tokens, output tokens, latency, timestamp, and final cost. Force one wrong-model or invalid-key error. Check whether the error path is logged clearly. Only then test streaming, tool calls, retries, and fallback.