Write-MATLAB-plugin.md

@@ -73,6 +73,18 @@ args = anywave('init', varargin);
 disp(args.plugin_option1); % value for plugin_option1 from the command line.   
 disp(args.plugin_option2); % value for plugin_option2 from the command line.
 ````
+However, this is possible only if we inform AnyWave about plugin_option1 and  plugin_option2.   
+Otherwise, an error will occured when using the command line saying that plugin_option1 and plugin_option2 are unknown options.    
+
+#### Register specific options
+To add support for specific command line option, add a file called arg.json in the plugin folder.   
+This is a JSON file that must be like this:    
+````json
+{
+     "Parameters" : ["plugin_option1", "plugin_option2"]
+}
+````
+
 # Compiled plugin
 Using the MATLAB Compiler, you can create a standalone version of your plugin.    
 AnyWave can call the standalone version of your plugin if you add the following line in desc.txt: