Good question.  The Cluster Agent is the newest agent from AppDynamics to make monitoring the cluster in a micro-services environment for efficient.

I would check out the following link but I put some high level requirements below:

https://docs.appdynamics.com/display/PRO45/Cluster+Agent+Requirements+and+Supported+Environments

The Cluster Agent requires the following:

• AppDynamics Controller versions 4.5.17+ and later.
• Kubernetes version 1.14 or later with the Kubernetes metrics-server deployed and enabled on the cluster.
• A cluster that you have access to and want to monitor.
• Sufficient Server Visibility licenses. The Cluster Agent consumes one Server Visibility license. See License Management.
• A Docker registry from which the AppDynamics Operator will download the Cluster Agent container image. Part of the installation is building the container image, so you need to have permission to read and write to your local Docker registry.

The Cluster Agent is compatible with:

• Kubernetes versions, 1.11, 1.13, 1.14 or later with the Kubernetes metrics-server deployed.
• Amazon EKS version 1.11, 1.13, 1.14 with the Kubernetes metrics-server deployed.
• Azure AKS version 1.11, 1.13, 1.14 with the Kubernetes metrics-server deployed.
• Google GKE version 1.14 with the Kubernetes metrics-server deployed.
• Red Hat OpenShift versions 3.9, 3.11 and 4.x. Please note metrics-server is not shipped with OpenShift, it needs to be deployed separately. The CRI-O container runtime is supported on versions 4.2.7 and above.
• kubectl version 1.11.3 or later.

For more information on this new agent please see here:

https://docs.appdynamics.com/display/PRO45/Monitoring+Kubernetes+with+the+Cluster+Agent