ansible-doc
Display information on modules installed in Ansible libraries.
TLDR
List available action plugins (modules)
$ ansible-doc --list
List available plugins of a specific type
$ ansible-doc --type [plugin_type] --list
Show information about a specific action plugin (module)
$ ansible-doc [plugin_name]
Show information about a plugin with a specific type
$ ansible-doc --type [plugin_type] [plugin_name]
Show the playbook snippet for action plugin (modules)
$ ansible-doc --snippet [plugin_name]
Show information about an action plugin (module) as JSON
$ ansible-doc --json [plugin_name]