Hi,
You don't need an agent to susccessfuly scan a linux device.
When you want to scan Linux devices with Lansweeper, you have to use ssh.
You can read in this article how to prepare your linux computer: http://www.lansweeper.com/kb/34/How-to-scan-Linux-computers.html
For the rest you have to make sure that you have a ssh credential mapped to a scanning method.