Transition states - Advanced features - Mercado Pago Developers
Which documentation are you looking for?

Do not know how to start integrating? 

Check the first steps

Transition states

In addition to handling conventional payment statuses (pending, approved or rejected), the Status Screen Brick also provides an additional experience for pending payments by Challenge, in the case of 3DS 2.0, or other cases that require redirection to external domains.

status-screen-transition-states

The integration process follows the same structure as the other states. Check out here for more details on the process.