# API Error Response Best Practice
source: https://developer.mastercard.com/mastercard-send/documentation/implementation/error-best-practice/index.md

The information that was on this page has been superseded:

* For API service error codes, see the Error Codes section in the API documentation for the Mastercard Send service you are using.

* For gateway error codes, see [this page](https://developer.mastercard.com/platform/documentation/errors-and-troubleshooting/oauth1-and-mtls-error-codes/).