Some questions about the AI...

[Taqwus]

Eh, just infer it and figure that the AIs aren't obligated to tell you how they REALLY feel, just like how a human player might attempt a surprise Alpha Strike.

If they're massing troops onto the border or lobbing Imprint Souls at you, you can pretty much safely infer that they don't like you very much and it may be time to send reinforcements to the weaker provinces, whereas more minor harrassment like Call of the Winds doesn't mean that much other than perhaps probing prior to an attack.

Well, if it were a human it'd be a probe -- to gather province name, check for presence of domes, check local defenses, perhaps roughly estimate what magics your pretender started with in case your guys cast Bless or determine your theme or how much you bother equipping or so forth. It's not a very subtle probe, and you know the caster's nation, but it'd perhaps be informative.

It _might_ be possible for a nasty global to provoke a war; I seem to recall suddenly once being involved in a three-front war in Dom I after casting The Looming Hell, and that seemed to be the obvious trigger. Might have been a coincidence however.