Checks#

Each entry in a collection’s checks: list has a kind and the keys that check type requires. Every check type is documented one per page in the check types reference:

checks:
  - kind: object
    schema: book
  - kind: object_field_type
    field: year
    type: integer
  - kind: markdown_title_matches_h1
  - kind: filesystem_name_matches_field

Text rules#

The text_* check types lint the item body as raw text, independent of markdown structure, and also apply to plain-text items (a .txt file or a markdown file with no frontmatter). Each is evaluated against a set of spans chosen by target:

• text_requires and text_forbids take a Go pattern, matched unanchored (it must appear somewhere in a span: unlike filesystem_name_regex, which anchors with ^...$). text_requires also takes match: any (default, at least one span matches) or match: all (every span must match).
• text_denylist takes values:, a list of literal substrings; regex metacharacters are inert.
• text_forbids may declare a fix:: a replacement template ($1, ${name} capture syntax) applied to the matched text by katalyst fix. The fix re-checks its own work and fails rather than writing a file the rule would still reject. text_requires and text_denylist are report-only.

Object-schema resolution precedence#

When an item is checked against an object schema, the schema is chosen highest-precedence first:

1. --schema <path> flag (applies to every selected item).
2. Inline schema: <name> key in the item’s frontmatter.
3. The collection’s object check (from schema: or an explicit entry), plus the matched variant’s schema: both apply, additively.

Markdown and filesystem checks always come from the collection (and the matched variant), even when --schema is used.