kubectl

name	kubectl
description	Execute kubectl commands to manage Kubernetes clusters — query pods and deployments, deploy applications, debug containers with logs and exec, update configurations, and monitor cluster health. Use when working with Kubernetes, asking for pod status, container logs, deployment updates, cluster diagnostics, or any kubectl operation.
license	MIT
metadata	{"author":"Dennis de Vaal <[e-mail]>","version":"1.0.0","keywords":"kubernetes,k8s,container,docker,deployment,pods,cluster"}
compatibility	Requires kubectl binary (v1.20+) and active kubeconfig connection to a Kubernetes cluster. Works on macOS, Linux, and Windows (WSL).

kubectl Skill

Execute Kubernetes cluster management operations using the kubectl command-line tool.

Overview

This skill enables agents to:

• Query Resources — List and get details about pods, deployments, services, nodes, etc.
• Deploy & Update — Create, apply, patch, and update Kubernetes resources
• Debug & Troubleshoot — View logs, execute commands in containers, inspect events
• Manage Configuration — Update kubeconfig, switch contexts, manage namespaces
• Monitor Health — Check resource usage, rollout status, events, and pod conditions
• Perform Operations — Scale deployments, drain nodes, manage taints and labels

Prerequisites

1. kubectl binary installed and accessible on PATH (v1.20+)
2. kubeconfig file configured with cluster credentials (default: ~/.kube/config)
3. Active connection to a Kubernetes cluster

Quick Setup

Install kubectl

macOS:

brew install kubernetes-cli

Linux:

apt-get install -y kubectl  # Ubuntu/Debian
yum install -y kubectl      # RHEL/CentOS

Verify:

kubectl version --client
kubectl cluster-info  # Test connection

Essential Commands

Query Resources

kubectl get pods                    # List all pods in current namespace
kubectl get pods -A                 # All namespaces
kubectl get pods -o wide            # More columns
kubectl get nodes                   # List nodes
kubectl describe pod POD_NAME        # Detailed info with events

View Logs

kubectl logs POD_NAME                # Get logs
kubectl logs -f POD_NAME             # Follow logs (tail -f)
kubectl logs POD_NAME -c CONTAINER   # Specific container
kubectl logs POD_NAME --previous     # Previous container logs

Execute Commands

kubectl exec -it POD_NAME -- /bin/bash   # Interactive shell
kubectl exec POD_NAME -- COMMAND         # Run single command

Deploy Applications

kubectl apply -f deployment.yaml         # Apply config
kubectl create -f deployment.yaml        # Create resource
kubectl apply -f deployment.yaml --dry-run=client  # Test

Update Applications

kubectl set image deployment/APP IMAGE=IMAGE:TAG  # Update image
kubectl scale deployment/APP --replicas=3          # Scale pods
kubectl rollout status deployment/APP              # Check status
kubectl rollout undo deployment/APP                # Rollback

Manage Configuration

kubectl config view                  # Show kubeconfig
kubectl config get-contexts          # List contexts
kubectl config use-context CONTEXT   # Switch context

Common Patterns

Debugging a Pod

# 1. Identify the issue
kubectl describe pod POD_NAME

# 2. Check logs
kubectl logs POD_NAME
kubectl logs POD_NAME --previous

# 3. Execute debug commands
kubectl exec -it POD_NAME -- /bin/bash

# 4. Check events
kubectl get events --sort-by='.lastTimestamp'

Deploying a New Version

# 1. Update image
kubectl set image deployment/MY_APP my-app=my-app:v2

# 2. Monitor rollout
kubectl rollout status deployment/MY_APP -w

# 3. Verify
kubectl get pods -l app=my-app

# 4. Rollback if needed
kubectl rollout undo deployment/MY_APP

Preparing Node for Maintenance

# 1. Drain node (evicts all pods)
kubectl drain NODE_NAME --ignore-daemonsets

# 2. Do maintenance
# ...

# 3. Bring back online
kubectl uncordon NODE_NAME

Output Formats

The --output (-o) flag supports multiple formats:

• table — Default tabular format
• wide — Extended table with additional columns
• json — JSON format (useful with jq)
• yaml — YAML format
• jsonpath — JSONPath expressions
• custom-columns — Define custom output columns
• name — Only resource names

Examples:

kubectl get pods -o json | jq '.items[0].metadata.name'
kubectl get pods -o jsonpath='{.items[*].metadata.name}'
kubectl get pods -o custom-columns=NAME:.metadata.name,STATUS:.status.phase

Global Flags (Available to All Commands)

-n, --namespace=<ns>           # Operate in specific namespace
-A, --all-namespaces           # Operate across all namespaces
--context=<context>            # Use specific kubeconfig context
-o, --output=<format>          # Output format (json, yaml, table, etc.)
--dry-run=<mode>               # Dry-run mode (none, client, server)
-l, --selector=<labels>        # Filter by labels
--field-selector=<selector>    # Filter by fields
-v, --v=<int>                  # Verbosity level (0-9)

Dry-Run Modes

• --dry-run=client — Fast client-side validation (test commands safely)
• --dry-run=server — Server-side validation (more accurate)
• --dry-run=none — Execute for real (default)

Always test with --dry-run=client first:

kubectl apply -f manifest.yaml --dry-run=client

Advanced Topics

For detailed reference material, command-by-command documentation, troubleshooting guides, and advanced workflows, see:

• references/REFERENCE.md — Complete kubectl command reference
• scripts/ — Helper scripts for common tasks

Helpful Tips

1. Use label selectors for bulk operations:

   kubectl delete pods -l app=myapp
   kubectl get pods -l env=prod,tier=backend
   

2. Watch resources in real-time:

   kubectl get pods -w  # Watch for changes
   

3. Use -A flag for all namespaces:

   kubectl get pods -A  # See pods everywhere
   

4. Save outputs for later comparison:

   kubectl get deployment my-app -o yaml > deployment-backup.yaml
   

5. Check before you delete:

   kubectl delete pod POD_NAME --dry-run=client
   

Getting Help

kubectl help                      # General help
kubectl COMMAND --help            # Command help
kubectl explain pods              # Resource documentation
kubectl explain pods.spec         # Field documentation

Environment Variables

• KUBECONFIG — Path to kubeconfig file (can include multiple paths separated by :)
• KUBECTL_CONTEXT — Override default context

Resources

• Official kubectl Docs
• kubectl Cheat Sheet
• Kubernetes API Reference
• Agent Skills Specification

---

Version: 1.0.0
License: MIT
Compatible with: kubectl v1.20+, Kubernetes v1.20+