An overview of the methods available can be provided by means of the extensions information.
The URL for the overview looks as follows:

http(s)://[Hostname]/(Webapplication)/xml-editor.ashx 

The methods are viewed in XML view.
All extensions are listed by module and namespace. All methods are then displayed in each namespace with the expected parameters and return values. If a method is listed several times, then the signatures of the method are different.

Note:
The methods of the kernel are not listed in this overview however, since these are not extensions and no longer have to be integrated separately in the stylesheet.