Season rice in Zojirushi
Rice cookers excel at just making plain rice, and all you need is uncooked rice and water. If you go beyond that, though, there are possibilities galore. For instance, I like adding a couple tablespoons of olive oil to my rice cooker at the start of cooking; I find that it makes the rice softer and more interesting. Salt can be added as well, or you can substitute various liquids for some of the water.

So, if you just want plain rice, start with rice and water. If you want something else, then what you should start with depends completely on what the "something else" is. Experiment! The worst that can happen is that you waste some rice.