You can use these commands for working with requirements:

* View the current status compared to your requirements

fabric:status

* Define requirements on a profile

fabric:require-profile-set --minimum 1 --maximum 3 some-profile-id

* List the current requirements for the profiles

fabric:require-profile-list

* Delete requirements for a profile

fabric:require-profile-delete some-profile-id

Or you can define the requirements in a file called org.fusesource.fabric.requirements.json in the /fabric/configs directory of the registry if you prefer.