Authorization header:
Test and live data never mix: a test key only sees test payments and test balances.
Allowed IP addresses
Requests are accepted only from the IP addresses you allowed in your dashboard. Add the public IPs of your servers before your first call. A request from another address is refused with403 IP_NOT_ALLOWED, even with a valid key.
Base URL
Errors
A missing key returns401 AUTHENTICATION_REQUIRED, a wrong key 401 AUTHENTICATION_FAILED. Too many requests return 429 RATE_LIMIT_EXCEEDED. See Errors.