It's a Java application, so it's actually OS independent.
Moreover, it is almost DMBS-independent thanks to JDBC technology.
Why would you need to document that?
Java doesn't immediately mean OS independent for what it's worth. Quite close, though.
You should always document this stuff.
I also wondered what databases this tools supported. Java or JDBC is not mentioned in a place I could find. A shame, really. I understand developers prefer development over documentation, but this is underselling it a bit.