Ansible "grammar" is so weird.
- "become: true" means you want to execute stuff as super user (root)
- "creates: /some/file.txt" means "do not execute if file exists"
- when creating a cron, "env:yes" tells ansible to add the "job" as an environment variable into crontab
...
I'm a big fan of Ansible (as of now) but it is so weird. Thankfully they have a good documentation so you can at least find out how every module works.