Arnold's command line renderer is called kick. This reads an .ass file, renders the scene using Arnold and outputs an image file. Kick can also be used to query Arnold nodes for their parameters and default values. It can also be used for scene debugging.
Kick is included in the plug-in downloads. After installation you will find it in the bin subdirectory of the Arnold distribution.
As this is a frequently asked question we have provided both the question and answer in this thread.
Lee Griggs
Arnold rendering specialist
AUTODESK
