Inventory feature (only in 2.x builds, working on a new version for 3.x):

What is it?
HackedServer is a spigot and bungeecord plugin which
allows servers' owners to detect and automatically block
or punish players using unwanted mods. The plugin is ex-
tremely inexpensive in resources and runs on almost any
server without decreasing performance and although
there are bypass, HackedServer helps you to save a lot of
time by significantly reducing the number of cheaters.

How does it work?
When a player logs into your server he sends hidden
messages using a plugin messaging system, these mes-
sages are sent on different channels & if HackedServer
knows the channel - Then he can instantlv intercept and
analyze the message!