How does Sim AI work?

 I have no idea, I think I've seen "world scan" which is the AI scans the whole area that's loaded looking for interactions but it seems like they limit themselves from experimenting and have a strong preference for repeating interactions they've done before.

I'm also curious about the priority of stuff and even traits and moods that can modify priority.

*Interaction objects that have a "fun" rating of 8 or more seem to draw Sims to them obsessively. (For this reason I recommend NEVER getting your Sims nice computers as they will constantly be videogaming).

*Reacting to famous people (Get Famous)seems to have a high priority

*Quirks from Get Famous are high priority

*Club activities from Get Together seem to be low priority if they are present in the AI buffer at all?

*Fire reactions seem to be a top priority

*Going to work also seems pretty high

*React in disgust is at the top with fire reaction

*Dehydration doesn't seem to be a thing(unless mermaid or vampire) but Sims seem to want to drink water all the time?

*I have no specifics on what traits seem to control AI priorities. I think I've seen Evil, Good, and Goofball effect if Sims will do more mean, friendly, and funny interactions?

*Interacting with people they feel strongly about positive or negative.

*Get to Work's NPC employees seem bugged because their priority to do their work tasks is lower than being social with people they feel strongly about or to interact with famous people. There's no way to correct this as the game doesn't consider this "Slacking off".

*Recovering Sim removed items from inventory doesn't have enough priority! One time my Sim took out and set down their homework somewhere by them self and I was never able to find it again.

*Walls, furniture, and other obstructions might not be physically solid but instead Sims have a top priority to not walk through them but on rare occasions they can bug out and ignore this priority

Completing Whims seems almost completely user controlled. A Sim doesn't seem to be aware of their whims which feels disconnected.

The AI seems to remove things from cue if it has to wait too long to attempt to do them. This design is probably to keep from locking up on a task they can never do. This can be problematic when they are being user directed in social situations and just need to wait for social interactions to complete before acting on the cue'd action.

  ^I've also encountered a rare situation in the Magic dueling grounds where the AI was in a failing situation it was locked into and it began to spam the activity cue on it's own with an interaction that was part of the duel while waiting for the other person. It nearly crashed the game for as hard as it was spamming interaction cue until it was able to complete the activity. -A neat side note for AI behavior.

 The AI seems to have it's own segment with in the game engine. I've seen the Sim AIs of a large group lock and all Sims were still while the rest of the game remained unaffected this game behavior persisted for a few minutes and then the Sims seemed to snap out of it and resume their activities. 

 Sim AI seems to scan their path before ever starting their journey to make sure they can accomplish it. Sim AIs can react to another Sim's route even before the sim them self gets there. -I've seen Sims react to my famous Sims who weren't in the room but were on their way to that room(psychic powers? Nope it's a bug!).

**One tip I think I've developed from my observations is that the Sim AI's 'thinking' is different from the activity cue and sometimes it can be slow! BUT it might be independent of pausing time so if you're in a situation (like running a store in Get to Work) you may be able to pause time to give the AI 'time to think'. I am unsure about this and it needs more testing. 

 I have no real idea, I'm just guessing at all of this. Please fill me in! If you don't know either but have noticed your Sims have a high priority for some behavior please let me know.