Sandbox & test
Test credentials that send without burning Live debit — not production key cutover.
Sandbox traffic must not hit the wallet
A Live key in a test harness is an incident. Detect leaked Live credentials, freeze holds, and rotate before pilot volume.
Sandbox credentials that do not burn Live debit
Issue sandbox API keys that never hold or debit the prepaid wallet. Keep Live keys out of CI and prove cutover under Developers.
Sandbox reach is not production coverage
Sandbox destinations are for tests only. Never quote them as Live zones on a finance sheet or runway score.