[Question] What Are the X and Y Trainer AI Levels and how do they work?

[ClapSimulator]

Hey people, so I'm currently messing around with Pokemon X rom hacking using pk3DS and theres an option for trainers' "AI Level" which ranges from 0 to 255 and I haven't been able to find any info online for this in gen 6. I figure since I'm essentially making a difficulty hack, I want champion level AI, so I'm setting all the trainers to 7 since thats what Diantha's AI is normally. My problem is that there is no explaination as to what the different levels do and it doesn't seem like "bigger number equals better trainer" necessarily, since some trainers have AI of 128, 131, 133 (all double battles are like this, as well as 1 or 2 other single battles). And are the higher levels like 255 actually used? Because I find it hard to believe they programmed 255 different battle AI scripts. If anyone has any knowledge on what the AI Levels do and/or an explaination on how the AI Levels work in X and Y, it would be very appriciated. Thanks :)