System rules are enabled or disabled by the application as necessary. For example, when you create or delete a topology, the application enables or disables the associated system rules. Do not manually enable or disable system rules.
If you are building your own vertical application module or customizing an existing module, you can add feature rule plug-ins to manage the feature rules of your application. Refer to the "Adding Feature Rules" section in the Developer’s Guide for details about how to create a feature rules plug-in, how to write the rules themselves, set rule priorities, and how to install the new plug-in.