The MindLink API is more of a package-product, meaning it comes with functionality that your bots decide to use or not use depending on the requirements. Functionality here is not so "For my deployment I want X or Y" and is instead "This bot needs to do X." at which point you utilise X. Unlike the other products you don't need to enable X first, you just need to configure the management center and start working with your integrations.
The Management Center section later covers the process of setting up and configuring the API.
Developer references are available too, found here