How auto-complete works?

Just tried to press TAB/arrows etc  to complete @playername, but did not see any reaction...

I would assume it assumes based on potential partial matches.

I have player with 3 letters long name, I tried to enter 2 letters from his name and than press TAB/arrows and nothing happened

That isn't how it works. It works by looking for players based on that partially typed name, it has to way to handle 
conpletion using the client.

I don't get it... Can you explain this with example?

QZgYNTRCXGzxFud.jpg zloyadmin

I don't get it... Can you explain this with example?

@zloy -> plugin looks for any names that start with that and mentions the first matching, connected player.

oh, thanks, I will try this