I would like to amend the above suggestion:

Instead of adding an in-game command list.. Add these toggles to an option in the configuration menu so that players can turn them on and off there. Theres no need for players to have to remember these commands or look up a list to turn them on/off.

What can also be done is adding system messages when improper input has been made.
Ex. I just typed in /eicon

___________
/eicon
The following command is incorrect. /eicon toggles are
on
off
___________