YAML frontmatter

Change metadata without serializing the file.

Incise edits one frontmatter key at a time while preserving comments, key order, scalar spelling, and every unrelated line.

Inspect before editing

incise keys note.md
incise frontmatter-set note.md \
  --key publish.status \
  --value ready

Nested mappings use dotted paths such as publish.status. Sequence members use indexes such as authors[0].role.

Human context around metadata stays where its author placed it.

Unrelated scalar styles and key order are not normalized through a serializer.

Malformed or unsupported frontmatter produces a concrete refusal instead of a guess.

Incise is intentionally not a general-purpose YAML formatter. It is a narrow mutation layer for Markdown documents.