Welcome to Smogon! Take a moment to read the Introduction to Smogon for a run-down on everything Smogon, and make sure you take some time to read the global rules.
Its a bit annoying that you need to fully type out /tier nationaldex (uu, bh, monotype) when /tier natdex and /tier natdex ag both work. It would be nice to be able to abbreviate all national dex tiers as natdex (whatever)