This is an extension to Visual Studio 2015 or 2017 that allows to create XML documentation comments. It works like entering three slashes (///) in C# but you can use it also in C++ and it updates existing comments.
To insert XML comments just set the cursor to a function line and invoke the command Tools -Create/update XML comment.
This creates the comment block and you can fill the comment fields.
If the function signature changes later, you just call the command again and the comments gets updated without losing existing text:
Add missing comments and check if exising text needs to be updated.
If you invoke the comment for the first time the options dialog is shown where you can enter your user sign and define the comment block layout.
To change the options open Visual Studio options and go to the section XML Comments.