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Is there a command line interface for Rational Team concert to create user stories, tasks, .... ?

Accepted answer

There currently is no command line client for creating / managing work items.
This enhancement request is tracked in: Command line interface for work items (83846)
This enhancement request is tracked in: Command line interface for work items (83846)
Comments

I'll add the workaround here that Ralph already provided:
You can use the Eclipse CSV import. If you are willing to do some of your own coding you can try https://rsjazz.wordpress.com/2015/11/03/a-rtc-workitem-command-line-version-3-0/