# Frontmatter Operator plugin for Obsidian Frontmatter Operator, by pssah4, is a bulk-editing tool for YAML frontmatter in [[Obsidian]]. You first filter the vault down to a target set of notes using property conditions (property exists, equals, contains, is missing, and similar), with a live preview showing exactly which notes match before anything is touched. On the matched set you can then run batch operations: set a property to a value, delete a property, rename a key across every note, or merge properties. Before applying changes the plugin takes a snapshot, so a bulk operation that went wrong can be rolled back — the safety net that makes vault-wide metadata surgery reasonable rather than reckless. This solves the schema-migration problem every structured vault eventually hits: renaming `status` to `state` in 400 notes, backfilling a missing property on all notes of a type, or cleaning out an obsolete key. Done by hand this is hours of error-prone editing; done with scripts it requires writing and testing code. Frontmatter Operator makes it a filtered, previewed, undoable operation inside the app, keeping the metadata layer that [[Dataview plugin for Obsidian|Dataview]] and Bases queries depend on consistent. ## References - Download: https://obsidian.md/plugins?id=frontmatter-operator - Source code: https://github.com/pssah4/frontmatter-operator