I have set up a machine with Vagrant, and created a basic Ansible playbook for it. Everything works as expected when I run
vm-abla> vagrant provision
I managed:
vm-abla> ansible jon -i provisioning/hosts -a "echo 'TEST'" -vvvv -c ssh --user=vagrant --private-key=~/.vagrant.d/insecure_private_key
But if someone has a more elegant or secure solution, I'm interested.