📖 YAML Syntax & Validation Guide: Avoiding Indentation Mistakes

YAML Indentation Strictness and Whitespace Rules

YAML (YAML Ain't Markup Language) relies heavily on whitespace and indentation to indicate nesting levels. The official YAML specification strictly forbids tab characters for indentation; only spaces are permitted.

Mixing tabs and spaces or using inconsistent indentation offsets across child elements causes parsing failures in Kubernetes manifests and CI/CD pipeline definitions.