No one in a sane mind would provoke Rage. Your ally is no idiot
There is entry in AI_politics.txt file that determine how soon it will agree to a new treaty. Some AIs do it faster than others. Ask them later.
Yes, AI diplomacy is very limited. We shall wait for SEV.
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It is forbidden to kill; therefore all murderers are punished unless they kill in large numbers and to the sound of trumpets. - Voltaire