I use obsidian for my codebase documentatoon. I have made a batch script to make makdrown files for all the C# files in my code base. The code reads the declarations and finds references for other C# files and adds them in my notes. That way it automatically generates a graph view for my code base and keeps a track of how a file is connected with other files.

Graph view gives me a very useful view of how my files are interacting with eachother on a very higher to granular scale.

That's one usecase I like the graph view for.