What the mod does, as the mod name implies, is give the player a free pair of pants.
What exactly does it do? Well, when you make a singleplayer world for the first time or join a multiplayer server for the first time, you automatically obtain a free pair of leather leggings with a random color dye, and if you're lucky enough, a random name with +? modifiers that don't do anything.
The lore names are randomly picked from a list of words, which can all be configured. The mod can be installed just on the server side, as it adds no new items or blocks.
This mod was deemed a small one off mod not fit for public release, but I was asked to put it on here anyway, so here we are.