The EU4 devs have been using forum suggestions to aid gaps in AI

One fan in particular managed to reverse engineer AI behaviour in a way that was easier to understand than the code itself

Paradox Grand Strategy: From the Carnival of Lust to the Enlightened Times - The Something Awful Forums

Victoria 3 - Dev Diary #99 - Colossus of the South : r/victoria3

Europa Universalis IV - Development Diary 19th of July 2022

Europa Universalis IV - Development Diary 14th of June 2022, Page 5

AI enemy just walks through my fort

Why are the AI provinces never invested in Infrastructure? It is an indispensable investment to develop provinces as early as 15 devs, AI's must be wasting a ton of power developing their

How does the EU4 AI work? Paradox Interactive Forums

PSA : The AI is hardcoded to not regain manpower when disbanding units, even at 100% army professionalism. : r/eu4

Europa Universalis IV: Origins - Announcement Trailer : r/paradoxplaza

Europa Universalis IV - Development Diary 20th of December 2022 - Unit Pips Rebalance, Page 5