Which Kubernetes API version does it validate against?

Kubernetes 1.29+ schema by default (configurable). It flags resources using deprecated APIs that will be removed in future versions.

Does it check best practices or just syntax?

Both — syntax validation catches YAML parse errors and missing required fields; best-practice checks flag missing resource limits, missing readiness probes, privileged containers, and hostPath mounts.

Can I validate multi-document YAML (--- separators)?

Yes — paste a file with multiple YAML documents separated by ---. Each document is validated independently and errors are reported per document.

Kubernetes Manifest Validator

DevTools Surf

Example: Kubernetes Manifest Validator

A worked example, rendered from real sample data. Sign in to run the tool on your own input.

Input

apiVersion: v1
kind: Pod
metadata:
  name: nginx-pod
  namespace: default
spec:
  containers:
  - name: nginx
    image: nginx:latest

Output

Kubernetes Manifest Validation
──────────────────────────────────────────────────
Kind: Pod
Name: nginx-pod
Namespace: default
Valid: YES

Issues:
  ✗ Missing labels. Add labels for pod selection.
  ✗ No resource limits/requests defined. Add for proper scheduling.

About Kubernetes Manifest Validator

Kubernetes Manifest Validator preview - Developer Utilities tool

Validate Kubernetes YAML manifests for correctness and best practices. Part of the DevTools Surf developer suite. Browse more tools in the Developer Utilities collection.

Use Cases

Validate Deployment, Service, ConfigMap, and Ingress YAML before applying to a cluster.
Check that resource requests/limits are set on all containers to prevent resource contention.
Verify RBAC permissions follow least-privilege principles before applying to a production cluster.
Detect deprecated API versions (e.g., apps/v1beta1) before upgrading Kubernetes.

Tips

Validate manifests locally before 'kubectl apply' — kubernetes rejects malformed YAML at apply time but doesn't always give clear error messages.
Check resource requests and limits on every container — missing limits allow a single pod to consume all node resources and evict other pods.
Validate RBAC manifests carefully — overly broad ClusterRoleBindings are the most common security misconfiguration in Kubernetes.

Fun Facts

Kubernetes was open-sourced by Google in 2014, derived from Borg, Google's internal cluster management system that had been running since 2003. The Kubernetes API remains remarkably backward-compatible with its 2014 design.
Kubernetes had 1.3 million YAML manifests committed to public GitHub repositories by 2022. 'YAML engineer' became an ironic job title reflecting how much configuration Kubernetes requires.
The CNCF's 2023 survey found that 96% of respondents were using or evaluating Kubernetes, up from 58% in 2018 — making it the fastest-adopted infrastructure technology since Linux.

FAQ

Which Kubernetes API version does it validate against?: Kubernetes 1.29+ schema by default (configurable). It flags resources using deprecated APIs that will be removed in future versions.
Does it check best practices or just syntax?: Both — syntax validation catches YAML parse errors and missing required fields; best-practice checks flag missing resource limits, missing readiness probes, privileged containers, and hostPath mounts.
Can I validate multi-document YAML (--- separators)?: Yes — paste a file with multiple YAML documents separated by ---. Each document is validated independently and errors are reported per document.

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