How to add a UI element on a GameObject through Custom Inspector code example

Example 1: unity change tag in script

gameObject.tag = "NewTagName"

Example 2: on hover add class on children jquery

$(document).ready(function()
  {
    $('li.active').hover(
      function(){ 
        $(this).children("a").addClass("icon-white"); //Add an active class to the anchor
      },
      function() {
        $(this).children("a").removeClass("icon-white"); //Remove an active class to the anchor
      }
   )
 });