How does it work?
This function is available in "Conversations" as well as user, company, and deal profiles.
Conversations
On the bottom of your window, choose the mode, Note, instead of Chat (the writing field will turn yellow). Now, type "@".
From the drop-down menu, choose the agent you want to notify about your note.
After adding the note, the agent the will be able to see the notification in the top-right corner of the app.
User, company and deal profiles
This mechanism works in a similar way when adding notes in profiles.