NO DEVELOPMENT BOOKS?

I am using 1.5.8 on a server 1.12.2 but I want to migrate everything I have to 1.13.1 but I have found the unpleasant surprise that there are no development libraries that I need for what we have created and it was the reason to buy this plugin please !!! put back the same libraries we need for development and if they have changed functions etc .. please put examples and update on your website but please! I do not understand why they are not, please we need you to put the libraries back:
import com.kirelcodes.miniaturepets.api.pathfinding.Pathfinder;
import com.kirelcodes.miniaturepets.api.pets.APIMob;
etc .. we hope urgent response thanks friends!
 
They are not or do not exist, I need to know how to do what I could do before please, I would need to know where all this is so I can do the same:
mob.updateObject("hungerLevel", level);
mob.getObject("hungerLevel")).intValue();
mob.getHealth()
mob.setHealth(0)
mob.getInventory().addItem(itemStack);
mob.teleport(lBoss);
onMobDefensa(MobDamagedByEntityEvent event)
public void onMobAttack(MobDamageEntityEvent event)
mobDeath(MobDeathEvent event)
MobContainer mobContainer = new MobContainer(model, "GorilaMob", mobabf.gorilavida, mobabf.gorilavelocidad, EntityType.valueOf(mobabf.gorilatipo), mobabf.gorilatipo);
mob.addObject("hungerLevel", hambre);
mob.addObject("nombremob", "GorilaMob");
Or does it no longer exist? if it is the case please re-implement thanks!