How do the actions of the king john define him? and what is he unfit to be?

John had the administrative ability of a great ruler but, from the moment he began to rule, rivals and traitors tried to cheat him out of his inheritance. As he wrestled with one problem, more enemies sprang upon his back.

John had potential for great success. He had intelligence, administrative ability and he was good at planning military campaigns. However, too many personality flaws held him back. 
John was a tyrant. He was a wicked ruler who did not behave like a king. He was greedy and took as much money as he could from his people. Hell is too good for a horrible person like him.

according to Richards will king John was unfit to rule

It may be written down (as in the united states) or it may be unwritten (as in great britain). this is the 1787 meeting at which the  constitution of the united states  was debated and agreed upon. this was a 1787 meeting called by congress to amend the articles of the confederation.