markdown-post-frontmatter-validation
Markdown Post Frontmatter Validation
Concept of the skill
What it is: The project-specific validation discipline for the YAML frontmatter on markdown posts. Mental model: Frontmatter is a typed interface between content files and the site runtime. Why it exists: Routing, indexes, tags, dates, and previews all depend on frontmatter being complete and unambiguous. What it is NOT: It is not general YAML schema design, parser performance work, or debugging a specific failed build. Adjacent concepts: Content schemas, slug derivation, controlled vocabularies, date normalization. One-line analogy: It is the checklist that makes every post safe for the build to consume. Common misconception: If the markdown renders, the frontmatter is good enough; metadata can break listing pages even when body content renders.