#Edit Upvote here for Unity to do it by default: https://issuetracker.unity3d.com/is...ml-files-with-useful-descriptions-are-missing --- I've noticed something interesting. Net dlls provided with Unity installation in for ex. C:\Program Files\Unity\Hub\Editor\2019.2.11f1\Editor\Data\MonoBleedingEdge\lib\mono\4.7.1-api don't include XML files and thus all VERY useful descriptions are missing in Visual Studio. Because of that I used to google every single time I wasn't sure how one of function works. For example just now I was checking if File.Move will safely move my file if destination file already exists. Unity shows only this: It seems that this is very easy to fix simply copy over all .xml files from C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.7.1 (If u don't have them simply install Microsoft .NET Framework Developer Pack - link to 4.7.1v) to Unity folder mentioned at the top. Restart Visual Studio to get this: Even better, select Move click F12 for even more info: Answer to my question is right there "T:System.IO.IOException: The destination file already exists." Btw Windows platform.