obsidian-yaml-frontmatter_skill

Overview

This skill standardizes YAML frontmatter in Markdown files so vault content uses consistent property names, formats, and value types. It helps create or update frontmatter blocks, enforce lowercase keys, normalize tags and dates, and validate link and quoting rules. Use it to ensure predictable metadata across notes and automate cleanup of inconsistent frontmatter.

How this skill works

The skill inspects the top-of-file YAML block and either inserts or updates properties according to a standard property set (title, created, tags, sources, etc.). It enforces a single YAML block at the top, a blank line after the closing ---, lowercase keys, list-form tags without hashtags, YYYY-MM-DD dates, and quoted wiki links or special-character values. It can validate structure and fix common issues like duplicate keys, unquoted colons, or inline tag lists.

When to use it

• Adding frontmatter to new Markdown files so metadata follows vault standards
• Updating existing frontmatter to convert keys to canonical names (e.g., date → created)
• Normalizing tag formatting (remove #, convert to list form)
• Validating and fixing wiki links and values containing special characters
• Preparing notes for automated processing that requires consistent metadata

Best practices

• Keep only one YAML block at the very top and leave a blank line after the closing ---
• Use lowercase, canonical keys (title, created, tags, sources, author, links, attendees)
• Format dates as YYYY-MM-DD and avoid time components in frontmatter dates
• List tags as dash-prefixed items and never include # in YAML tag values
• Wrap wiki links and values containing :, #, or numeric-looking strings in quotes
• Avoid duplicate properties; map synonyms to one canonical key (e.g., date → created)

Example use cases

• Convert a folder of imported articles to use created, source, author, and tags consistently
• Fix meeting notes: add event_date, attendees (quoted wiki links), and meeting tags
• Normalize daily journal files to include title, created, and plain-text tag lists
• Validate and clean frontmatter before running search-and-replace workflows
• Prepare relational pages with sources and links formatted as quoted wiki entries