We should create some basic overview for every script we ship, this should contain description of service provided by script, list of switches, list of possible arguments and some examples with expected output. add-user script is mentioned in Chapter 4 of admin guide: http://documentation-devel.engineering.redhat.com/docs/en-US/JBoss_Enterprise_Application_Platform/6.2/html-single/Administration_and_Configuration_Guide/index.html#chap-User_Management
*** Bug 1014127 has been marked as a duplicate of this bug. ***
There is already quite good content inside A&C guide http://documentation-devel.engineering.redhat.com/site/documentation/en-US/JBoss_Enterprise_Application_Platform/6.3/html-single/Administration_and_Configuration_Guide/index.html#chap-User_Management