When processing files it’s often a good idea to specify a ‘root’ folder. The file path is then calculated as being relative to this root folder which can result in shorter file paths. For example, if you have an original file in /Volumes/Media/Online Media/Project/ and want to build a proxy of that file in /Volumes/Media/Proxies then you should specify /Volumes/Media/Online Media as the root folder or the proxy will be /Volumes/Media/Proxies/Volumes/Media/Online Media/Project/ rather than /Volumes/Media/Proxies/Project/

If you use a watch folder files are taken relative to the watch folder itself but when dragging files on the worker icon you need to specify a root unless you want the entire original file path to be used. For server-triggered actions the path is taken relative to the root specified by any applicable path mapping. (To specify a root even though the original file path is already correct, specify a dummy path mapping from the root to itself.)