This is an unashamed quick n dirty standalone version of Visual Studio Syntax Visualizer

https://docs.microsoft.com/en-us/dotnet/csharp/roslyn-sdk/syntax-visualizer?tabs=csharp

I created it because I didn't want to have to open visual studio each time to use the visualizer

The original was created by Sam Harwell (I think) so in essence. ... follow whatever he chose as the licence

To use: Simply paste your code and click that button.