Gauntlet is a framework to run sessions of projects in Unreal Engine that perform tests and validate results. It is specifically designed for, but not limited to, running Unreal sessions on a variety of platforms. An Unreal session is all of the processes needed to execute a game with the Unreal engine. For example, a multiplayer game may require four clients and a server.
Gauntlet does not require any specific game-side automation code or test framework — how your game performs tests is entirely up to you. There is however a Gauntlet Plugin that provides a useful TestController class to assist with puppeteering and monitoring a game instance. It is well suited to smoke tests that require several steps to execute, but it is entirely optional.