Ansible currently is broken. As noted by sturm/Guest2732 on #guix, running any `ansible-<command>' commands leads ansible to think that we are calling the `ansible' script directly, instead of via a `ansible-<command>' script.
This is related to [1], and possibly might be solved by [2]. [1]: http://lists.gnu.org/archive/html/bug-guix/2017-05/msg00015.html [2]: http://lists.gnu.org/archive/html/guix-devel/2017-11/msg00017.html