This post discusses how to use Kubernetes clusters for CI/CD agents with Buildkite's agent-stack-k8s, which is currently in beta. The author provides detailed instructions on setting up a Kubernetes cluster in four different clouds (kind, AKS, EKS, and GKE) and adding secrets to the pipeline. They also explain how to install the Helm chart for agent-stack-k8s and run a Buildkite pipeline. Finally, they emphasize the importance of cleaning up resources after use to avoid unnecessary costs.