This is a placeholder. It exists so the MDX pipeline has something to compile, the index page has something to list, and the metadata schema has something to validate.
Posts export a metadata object rather than carrying YAML frontmatter. That
comes free with @next/mdx, avoids a frontmatter parser, and means the shape is
validated by Zod at build time instead of trusted at runtime.
Because MDX is JSX, a post can import and render real components — an interactive demo sits inline in the prose rather than living in a separate sandbox. That is the reason this site uses MDX in the repo instead of a CMS.