dedupe-frontmatter-links

name	dedupe-frontmatter-links
description	Deduplicate wikilinks in any YAML frontmatter property that contains multi-line wikilink arrays. Removes case-insensitive duplicates like [[ml]] and [[ML]], keeping the version with more capital letters. Use when cleaning up frontmatter, fixing duplicate links, or normalizing link casing.
allowed-tools	Read, Grep, Glob, Bash

Dedupe Frontmatter Links

Deduplicate wikilinks in YAML frontmatter properties using case-insensitive comparison.

Problem

In Obsidian, users may accidentally add duplicate wikilinks to frontmatter properties that differ only in case:

RELATED_TO:
  - "[[ml]]"
  - "[[ML]]"
  - "[[Machine Learning]]"

These duplicates clutter the frontmatter and can cause issues with queries and navigation.

Solution

This skill identifies and removes case-insensitive duplicate wikilinks, keeping the version with the most capital letters (as it's typically the more "canonical" form):

• Before: [[ml]], [[ML]], [[Ml]]
• After: [[ML]] (most capitals wins)

Instructions

Use the Python helper script at .claude/skills/dedupe-frontmatter-links/scripts/dedupe_links.py:

uv run --with pyyaml .claude/skills/dedupe-frontmatter-links/scripts/dedupe_links.py <command> [args]

Helper Script Commands

# Scan directory for duplicate links (dry-run, shows what would be changed)
uv run --with pyyaml .claude/skills/dedupe-frontmatter-links/scripts/dedupe_links.py scan <directory>

# Fix all duplicate links in directory
uv run --with pyyaml .claude/skills/dedupe-frontmatter-links/scripts/dedupe_links.py fix <directory>

# Check single file for duplicate links (dry-run)
uv run --with pyyaml .claude/skills/dedupe-frontmatter-links/scripts/dedupe_links.py check <file_path>

# Deduplicate links in single file
uv run --with pyyaml .claude/skills/dedupe-frontmatter-links/scripts/dedupe_links.py dedupe <file_path>

Examples

Scan SlipBox for duplicate links

uv run --with pyyaml .claude/skills/dedupe-frontmatter-links/scripts/dedupe_links.py scan "02-SlipBox"

Fix all duplicates in the vault

uv run --with pyyaml .claude/skills/dedupe-frontmatter-links/scripts/dedupe_links.py fix "."

Check a single note

uv run --with pyyaml .claude/skills/dedupe-frontmatter-links/scripts/dedupe_links.py check "02-SlipBox/Machine Learning.md"

Deduplication Rules

1. Case-insensitive matching: [[ml]] and [[ML]] are considered duplicates
2. Prefer more capitals: When duplicates exist, keep the version with most uppercase letters
3. Tie-breaker: If capital count is equal, keep the first occurrence
4. Any wikilink array property: Processes any frontmatter property that contains multi-line wikilink arrays
5. Preserves order: Non-duplicate links maintain their original order

Output Format

The script outputs JSON with scan/fix results:

{
  "total_files_scanned": 100,
  "files_with_duplicates": 3,
  "total_duplicates_found": 7,
  "files": [
    {
      "file": "02-SlipBox/Machine Learning.md",
      "properties": {
        "RELATED_TO": {
          "before": ["[[ml]]", "[[ML]]", "[[deep learning]]"],
          "after": ["[[ML]]", "[[deep learning]]"],
          "removed": ["[[ml]]"]
        }
      }
    }
  ]
}

Notes

• The script automatically detects any property with multi-line wikilink array values
• The script skips hidden/system directories: .claude, .obsidian, .trash, .git, node_modules
• Always run scan first to preview changes before using fix
• Links with different display text (e.g., [[ML|machine learning]]) are compared by their target only
• Section links (e.g., [[Note#Section]]) compare only the note name portion