Do not judge a relay by one request. Test short connectivity, sustained requests, long-task recovery, billing behavior, and provider rules.
Sustained test
Run 10 to 20 requests and at least one real coding task before increasing budget.
Record model names, errors, latency feel, and billing changes.
Short test
JuCodex: 100% availability, 1638 ms average latency, current status up.
YunDou: 100% availability, 1983 ms average latency, current status up.
linkapi: 99.9% availability, 2308 ms average latency, current status up.