Auth with 3DS should be used for payments authenticated with 3DS.
You need to get authorization before you actually capture any funds. An authorization is a response from a financial institution indicating that payment information is valid and funds are available in the payer’s account.
Note that Capture is a separate operation with its own unique endpoint.
An Auth with 3DS call followed by a Capture call is equivalent to using Pay with 3DS (ie. Pay = Auth + Capture).
The request model for Auth with 3DS is Authorize. Objects like agreement, authentication, order, billing and action (each with nested fields) are included.