The best way to judge an AI API relay is to treat it like production infrastructure. Start with three criteria: first, endpoint consistency; second, transparent model mapping; third, a response path that behaves the same in local development and on a server. A relay that looks simple on paper but breaks standard SDK behavior will slow you down.
For a practical smoke test, configure one environment variable, run a short request, and inspect both the output and the failure mode. Good tests are small: one prompt, one model, one minute. If the relay is stable, you should see normal headers, a usable completion, and no unexpected authentication loop. That applies whether you are wiring a Claude client, an internal app, or a batch script.
Example configuration:
If your SDK prefers ANTHROPIC_BASE_URL, you can map the same relay concept there as well. The key idea is
to keep the app-side changes minimal while validating transport, latency, and model availability. In a small team,
that simplicity matters more than any flashy dashboard.
What to verify after the first request
- The base URL includes the correct path segment, usually
/v1. - The key is accepted without extra proxy headers or custom signing.
- The returned model matches the one you selected in the client.
- Error messages are clear enough to diagnose routing or quota issues.
If everything passes, you can gradually move from a smoke test to a broader integration test: a longer prompt, a second model, and a retry scenario. That gives you a realistic view of how the relay behaves under normal usage. For teams wanting an OpenAI-compatible relay, 59API is one place to compare endpoint behavior and client fit.