Playbooks are task-based graphical workflows that are used to fully or partially automate the response to an ASM security risk. The playbook for Active Response is authored by a team of Cortex Xpanse security researchers and is based on the the investigation and remediation tactics we see utilized by our most sophisticated Cortex customers.
In practice you should not need to interact directly with the Active Response playbook since it is automatically assigned to applicable alerts and can be tracked and interacted with easily from the Incidents user interface (UI).