Use Custom Headers with Credentials

Custom headers are a way for a remote system to define parameters it needs as input to respond to a request. Using a custom header is similar to having a function in a piece of code and defining input parameters or arguments that allow the caller to provide input.

You can add custom headers to named credentials and external credentials. In most cases, it’s best to associate headers with the external credential, rather than the named credential, because external credentials are meant to encapsulate authentication details. For example, define custom authorization headers in an external credential to use consistent authentication across all named credential endpoints using the same external credential.