Thanks, I check the thread

! But is it possible that AI plots war without being in WHEOOHRN first?
WHEOOHRN (We have enough on our hands right now) or WHEOOH is a denial that occurs when the AI is preparing a certain amount of UNITAI_ATTACK, UNITAI_CITY_ATTACK...in a nutshell certain types of units, not in the form but in the script. It is given a delay before the war is started.
This denial or excuse is implemented simply to make the AI less erratic and manipulated (in the direct sense; perhaps the idea of bribing someone onto them never crossed the devs' minds). If we could bribe the AI while preparing a war, the concept of "Oh my god, the AI is plotting" wouldn't be as scary as it is now.
Also, that restricts the number of simultaneous wars against one AI. The conceptors know their AI coding would incredibly fail against many foes.
Now, is it possible the AI skips the plotting period? Yes.
Dagger is a type of opportunistic war whose preparation duration is simply one turn.
Refusing a tribute may lead to those rare cases of automatic wars. Most of the time, that triggers (if you're unlucky) the sneak attack type of war, which is easily neutralized by a simple begging. Only type of war that can be neutralized by a beg, thus an automatic 10 turns forced peace.
The other particularity of sneak attacks (again triggered by tribute refusal) is even an AP resolution for war was passed and the sneaky AI is now at war, he will still prepare its sneak attack.
There is a urban legend that begging, thus 10 turns of forced peace increases the chance the AI revokes its war planning. Totally false. When an AI returns to its choice and revokes plotting, it's independent of you. Remember the "fixed" war preparation duration and the number of units with such and such scripts thingies. Well, there is a relationship between those two factors and the empire growth (mainly population IIRC). If the the number of units with pertinent scripts is insufficient versus the empire growth, then the AI may revoke the war. Why is it like this? I suspect this has to do if you can grow like a madman and insufficiently build units, the devs concluded the AI is under a phase of expansion and there is no place for a useless war. Just like we teach to noble players, don't war too much if you got plenty of good lands already. It's useless or overkill.
The only factor that "may" help you is to help them in their growth, by raising their happy and health caps.
Now to return to the main subject, WHEOOH is an excuse under the form of a fist in BUG, but doesn't appear when in semi-isolation with someone. Why? Well, BUG team slogan is gives all available information that could be already seen, but was irking in the original method. Originally, to know if some AI plots war, we had to check the diplo table each turn. Annoying for nothing. Thus BUG team eases the job. They don't furnish hidden info. When you see that denial, that is WHEOOH, that means there is a third party on your island...then no semi-isolation. In that situation, given there is no third party, you can't deduce if the AI is plotting and thus no fist ever in BUG.