Display documentation intellisense from <dll>.XML file
Visual Studio (and cs.exe) have the option of generating a .xml documentation file alongside the .dll & .pdb. This file enables documentation intellisense.
Linqpad should be able to provide this intellisense
It should already pick up XML documentation files if you have LINQPad Pro or Premium (i.e. with Intellisense).Make sure the XML files are in the same folder as the DLLs you're referencing.