You can use extension templates to define extensions in your user interface plug-in module. The vSphere Web Client SDK provides XML templates that you can include in the plugin.xml file. The templates use variable values that you provide to automatically create extension definitions.The vSphere Web Client SDK provides templates for a number of different extension types, including the data views in a vSphere object workspace and for inventory list extensions in the Object Navigator. You can find examples of templates among the sample material for each extension type. See Adding to vCenter Object Workspaces, and Extending the Object Navigator.