Ansible is an agentless automation and configuration-management platform. It normally connects to managed network devices through protocols such as SSH, NETCONF, or HTTP APIs, eliminating the requirement to install an agent on each target. Ansible playbooks use YAML, a human-readable declarative language that describes the desired configuration state. Its modules are primarily developed in Python, allowing the engineering team to create custom modules when built-in functionality is insufficient. Chef and Puppet traditionally use agent-based architectures in which software runs on managed nodes, making them inconsistent with the agentless requirement. NX-API is a programmable interface provided by Cisco NX-OS; it can execute commands and return structured data, but it is not a complete configuration-management platform offering declarative playbooks, inventory management, and extensible automation modules.