Goods transportation

Intermodel traffic you can see if it's loaded or not, Same with coal, logs, ore so on and so forth. General goods on flatcars. What about boxcars? If I send a driver to load or unload, how do I know if it's done?
Thanks in advance.

One way is to right-click on a wagon, then there's an option to display its properties. If usually takes a few seconds to appear. There might be other ways.

John