In the rich text editor:
@agrohimerz
In a comment:
[agrohimerz](https://chowlings.com/user/agrohimerz)
For Names and Avatars:
In the rich text editor:
%agrohimerz
In a comment:
[![agrohimerz's Avatar](https://chowlings.com/images/avatars/default.jpg)](https://chowlings.com/user/agrohimerz) [agrohimerz](https://chowlings.com/user/agrohimerz)