Frontmatter

A block of metadata at the very top of a document, set off from the body.

Markdown, MDX, AsciiDoc, and reStructuredText all accept the same fenced block in any of three flavors: YAML (---), TOML (+++), or JSON (;;;). AsciiDoc and rst fall back to a native header when no fence is present, using AsciiDoc attributes or an RST field list. XML and HTML have no fenced form, because their metadata lives in element attributes or head tags. A fenced block must be the first thing in the file, or manni meta won’t recognize it. Whichever flavor or format is used, manni meta reads only the frontmatter, never the body, and normalizes it to the same metadata shape it validates. See Supported formats for the fence flavors and where each format keeps its frontmatter.