Agentless tool means that no software or agent needs to be installed on the client machines that
are to be managed. Ansible is such an agentless tool. In contrast to agentless tool, agent-based
tool requires software or agent to be installed on the client. Therefore the master and slave nodes
can communicate directly without the need of high-level language interpreter.
An agentless tool uses standard protocols, such as SSH, to push configurations down to a device
(and it can be considered a "messaging system").