Clear Vehicles Error

[Impaholic]

Hello, I wanted to ask if I'm doing something wrong:

When I type "/clear vehicles 10 empty" or "/clear vehicles empty 10" the command does not go through, and I get the following erro: "Parse error: could not parse 10 / empty to Boolean" - I'm guessing I'm not typing the command correctly, but I haven't exactly been able to find any guides with a proper list of how each command functions, so I'm not super sure what I'm missing. Any help would be appreciated.

[Impaholic]

The normal command, IE "/clear vehicles", when I'm not trying to only clear vehicles in a certain radius / that are empty works fine btw.