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