A Mouse class object is an object that grants access to a player's mouse and keyboard. This object is only active when a Tool or HopperBin is selected and will disconnect all connections to itself when or if a Player de-selects their Tool or HopperBin that was using the object.

While active, scripts can detect keys pressed, mouse button selection, and the mouse's current target and where it hit in the Workspace.

You can get the Players mouse with the ":GetMouse()" method of the Players, it might not work while it is a newly added function though, you can, however, also get the player's mouse by placing a tool with a handle inside of the player's character. This will grant almost immediate access to the player's mouse.