format-markdown-mkdocs

Summarize and format markdown files, then apply mkdocs/material-compatible structural spacing fixes for math, list, and table blocks. Outputs to {filename}_f...

Security Scan

The skill's purpose (markdown formatting and mkdocs spacing fixes) matches the code and instructions, but there are notable inconsistencies: it ships Node code and a package.json but declares no runtime/install requirements, and the runtime will read/write files (including in-place edits and home-directory config), which the SKILL.md does not fully surface.

Purpose & Capability

The skill's name, description, SKILL.md, and scripts all describe a markdown formatter and structural fixer (coherent). However the package.json requires Node >=18 and several npm packages, yet the skill metadata declares no required binaries or install steps — an inconsistency. A consumer would reasonably expect the skill to require Node and to install dependencies (npm/yarn), so the lack of declared runtime/install requirements is disproportionate and confusing.

Instruction Scope

The SKILL.md workflow is focused on reading and formatting the user-specified file, generating an analysis file, possibly creating backups, and optionally editing the original file in-place. Those actions are within the stated purpose, but the instructions and code also permit in-place modification (user option 3) and writing new files ({filename}-analysis.md, backups). The runtime script also looks for EXTEND.md in several locations (cwd .claude path, $HOME, skillDir) and will apply those config values, which is expected for configurable behavior but may surprise users if they are unaware of that lookup.

Install Mechanism

There is no install spec (instruction-only), but the repo includes package.json and package-lock.json with dependencies (unified, remark-parse, remark-math, remark-gfm, unist-util-visit, etc.) and a Node script. To run the provided script you will need Node >=18 and to install those packages. The lack of an install mechanism or declared required binary (node) is a mismatch that can lead to silent failures or to someone installing dependencies manually from npm without guidance.

Credentials

The skill requests no credentials or secret environment variables. The code reads process.env.HOME (standard) to search for an EXTEND.md config; reading $HOME is reasonable for per-user config. No network access or external credentials are requested or implied.

Persistence & Privilege

The skill does not request persistent platform-level privileges (always is false). It reads and writes files only within the user's specified files, writes backup copies, and reads potential local EXTEND.md configuration files; it does not modify other skills' configs or request system-level persistence.

What to consider before installing

This skill appears to do what it says (format markdown and apply mkdocs/material spacing fixes), but there are important practical mismatches you should address before using it: - Runtime requirement: The package.json requires Node >=18 and npm packages. The skill metadata does not list Node as a required binary or provide an install step. You should only run this in an environment with Node 18+ and after running npm ci (preferably in a sandbox or isolated environment). - File writes and in-place edits: The tool can create analysis files, backup files, and — if you choose the 'structural fixes only' option — modify the original file in-place. If you care about your originals, run it on copies or ensure backups are enabled. - Local config lookup: The script will look for EXTEND.md in the cwd under .claude/skills/format-markdown, in $HOME/.claude/skills/format-markdown, and in the skill directory. Review any such EXTEND.md files before running to avoid unexpected configuration changes. - Safety steps: Inspect EXTEND.md and the script (scripts/format-structure.mjs) yourself. Run the script first with a small test file and with a dry-run (if supported) or on copies. If you need the skill to be more transparent, ask the maintainer to add a clear install spec (node binary requirement and npm install instructions) and to document whether any network access or additional file paths will be used. Given these inconsistencies (missing runtime/install declaration and in-place editing capabilities), treat the skill as suspicious until you confirm runtime environment and review the config/backup behavior.

Markdown Formatter

Markdown formatting skill with two layers of processing:

1. Content formatting: analyze content, improve readability, and add metadata or structural aids when needed.
2. Structural compatibility fixing: apply mkdocs/material-safe spacing fixes for math, list, and table blocks without rewriting text content.

You MUST follow the workflow in the Workflow section below and must not skip required steps.

Core Principles

• Preserve original meaning and wording as much as possible.
• In content-formatting mode (Steps 2-5), metadata and structural aids may be added, such as title, summary, headings, emphasis, lists, tables, and admonitions.
• In Step 6 structural-fix mode, the script performs whitespace-only changes and never rewrites text content.

Principle	Requirement
Meaning Preservation	Preserve the author's meaning, tone, and wording as much as possible.
Structural Additions	In formatting mode, only add metadata or formatting structures that improve readability.
Whitespace-Only Script	Step 6 may only modify whitespace, empty lines, and structural spacing.
Rendering Safety	Ensure all changes improve markdown rendering stability in mkdocs/material style.
Traceability	Every meaningful change must be summarized in the final report.

---

Usage

The workflow has two phases:

1. Analyze and format content (Steps 1-5)
2. Apply structural compatibility fixes for mkdocs/material rendering (Step 6)

Claude performs content analysis and formatting first, then runs the structural compatibility script as the final cleanup step.

Workflow

Step 1: Read & Detect Content Type

Read the user-specified file, then detect content type:

Indicator	Classification
Has --- YAML frontmatter	Markdown
Has #, ##, ### headings	Markdown
Has **bold**, *italic*, lists, code blocks, blockquotes	Markdown
None of above	Plain text

If Markdown is detected, ask the user:

Detected existing markdown formatting. What would you like to do?

1. Optimize formatting (Recommended)
   - Analyze content, improve headings, bold, lists, tables, and readability
   - Run structural compatibility script afterward
   - Output: {filename}_formatted.md

2. Keep original formatting
   - Preserve existing markdown structure
   - Run structural compatibility script only on the copied file
   - Output: {filename}_formatted.md

3. Structural fixes only
   - Run the structural compatibility script on the original file in-place
   - No copy created; modifies the original file directly

Based on user choice:

• Optimize: Continue to Step 2 (full workflow)
• Keep original: Skip to Step 5, copy file, then run Step 6
• Structural fixes only: Skip to Step 6 and run on the original file directly

---

Step 2: Analyze Content (Reader's Perspective)

Read the entire content carefully. Think from a reader's perspective: what would help them quickly understand and remember the key information?

Produce an analysis covering these dimensions:

2.1 Highlights & Key Insights

• Core arguments or conclusions the author makes
• Surprising facts, data points, or counterintuitive claims
• Memorable quotes or well-phrased sentences (golden quotes)

2.2 Structure Assessment

• Does the content have a clear logical flow? What is it?
• Are there natural section boundaries that lack headings?
• Are there long walls of text that could benefit from visual breaks?

2.3 Reader-Important Information

• Actionable advice or takeaways
• Definitions and explanations of key concepts
• Lists or enumerations buried in prose
• Comparisons or contrasts that would be clearer as tables

2.4 Formatting Issues

• Missing or inconsistent heading hierarchy
• Paragraphs that mix multiple topics
• Parallel items written as prose instead of lists
• Code, commands, or technical terms not marked as code
• Obvious typos or formatting errors

Save analysis to file: {original-filename}-analysis.md

The analysis file serves as the blueprint for Step 3. Use this format:

# Content Analysis: {filename}

## Highlights & Key Insights

- [list findings]

## Structure Assessment

- Current flow: [describe]
- Suggested sections: [list heading candidates with brief rationale]

## Reader-Important Information

- [list actionable items, key concepts, buried lists, potential tables]

## Formatting Issues

- [list specific issues with location references]

## Typos Found

- [list any obvious typos with corrections, or "None found"]

---

Step 3: Check/Create Frontmatter, Title & Summary

Check for YAML frontmatter (--- block). Create it if missing.

Field	Processing
title	See Title Generation below
slug	Infer from file path or generate from title
summary	See Summary Generation below
coverImage	Check if imgs/cover.png exists in the same directory; if so, use relative path

Title Generation

Whether or not a title already exists, always run the title optimization flow unless auto_select_title is set.

Preparation — read the full text and extract:

• Core argument (one sentence: "what is this article about?")
• Most impactful opinion or conclusion
• Reader pain point or curiosity trigger
• Most memorable metaphor or golden quote

Generate 3-4 style-differentiated candidates:

Style	Characteristics	Example
Subversive	Deny common practice, create conflict	"All de-AI-flavor prompts are wrong"
Solution	Give the answer directly, promise value	"One recipe to make AI write in your voice"
Suspense	Reveal half, spark curiosity	"It took me six months to find how to remove AI flavor"
Concrete number	Use numbers for credibility	"150 lines of docs taught AI my writing style"

Present to the user:

Pick a title:

1. [Title A] — (recommended)
2. [Title B] — [style note]
3. [Title C] — [style note]

Enter number, or type a custom title:

Put the strongest hook first and mark it as recommended.

Title principles:

• Hook in the first 5 chars: create an information gap or cognitive conflict
• Specific > abstract: "150 lines" beats "a document"
• Negation > affirmation: "you're doing it wrong" beats "the right way"
• Conversational: like chatting with a friend, not a paper title
• Max ~25 chars: longer titles get truncated in feeds
• Accurate, not clickbait: the article must deliver what the title promises

Prohibited patterns:

• "浅谈 XX"、"关于 XX 的思考"、"XX 的探索与实践"
• "震惊！"、"万字长文"、"建议收藏"
• Pure questions without direction: "AI 写作的未来在哪里？"

If title exists in frontmatter and there is no H1 in the body content, YOU MUST insert the title as the first H1 (# {{title}}). Do not remove it. If frontmatter already has title, include it as context but still generate fresh candidates unless skipped by configuration.

Summary Generation

Generate 3 candidate summaries with different angles. Present to the user:

Pick a summary:

1. [Summary A] — [focus note]
2. [Summary B] — [focus note]
3. [Summary C] — [focus note]

Enter number, or type a custom summary:

Summary principles:

• 80-150 characters, precise and information-rich
• Convey the core value to the reader, not just the topic
• Vary angles: problem-driven, result-driven, insight-driven
• Hook the reader: make them want to read the full article
• Use concrete details (numbers, outcomes, specific methods) over vague descriptions

Prohibited patterns:

• "本文介绍了..."、"本文探讨了..."
• Pure topic description without value proposition
• Repeating the title in different words

If frontmatter already has summary, skip selection and use it.

To make the summary appear visibly, generate it following the Admonition Syntax Rules. Place it after the H1 title:

!!! example "Summary"

    Here is the summary you generated.

EXTEND.md skip behavior: If auto_select: true is set in EXTEND.md, skip title and summary selection and generate the best candidate directly without asking. The user may also set auto_select_title: true or auto_select_summary: true independently.

---

Step 4: Format Content

Apply formatting guided by the Step 2 analysis. The goal is to make the content scannable and the key points easy to grasp.

Formatting toolkit

Element	When to use	Format
Headings	Natural topic boundaries, section breaks	##, ### hierarchy
Bold	Key conclusions, important terms, core takeaways	**bold**
Unordered lists	Parallel items, feature lists, examples	- item
Ordered lists	Sequential steps, ranked items, procedures	1. item
Highlights	Critical details, important comparisons for quick attention	==text==
Color highlight	Colored emphasis where standard bold is insufficient	<span style="color:red;font-weight:bold">text</span>
Tables	Comparisons, structured data, option matrices	Markdown table
Code	Commands, file paths, technical terms, variable names	`inline` or fenced blocks
Blockquotes	Notable quotes, important warnings, cited text	> blockquote
Admonition	Definitions, examples, notable warnings, conclusions	Follow Admonition Syntax Rules below
Separators	Major topic transitions	---

Admonition Syntax Rules

Strict enforcement. When using MkDocs-style admonitions (e.g. !!! note, !!! example, !!! warning), you must follow these indentation rules strictly. Markdown parsers require content inside the block to be indented.

Correct format:

!!! note "Title Text"

    This is the content. It must start with 4 spaces, and the above line is empty.

    This is a second paragraph. It also needs **4** spaces indentation.

    - List items also follow. The end line should have an empty line with no indent below.

This is the line outside admonition (correct).

Incorrect format (DO NOT DO THIS):

!!! note "Title Text"
This content has no indent. (Wrong - breaks indentation rule)

!!! note "Title Text"

    First paragraph ok.

Second paragraph has no indent. (Wrong - breaks the block)

Syntax rules:

1. Indentation: All content belonging to the admonition must be indented 4 spaces relative to the !!! line.
2. Paragraph breaks: Blank lines inside the block must also preserve block structure; ensure the next paragraph starts with 4 spaces.
3. Nested lists/code: If using lists or code inside an admonition, indent them 8 spaces total.
4. Consistency: Do not mix tabs and spaces. Use 4 spaces consistently.

Formatting principles — what NOT to do

• Do NOT add invented facts, explanations, or commentary
• Do NOT delete or shorten valid original content without user intent
• Do NOT rephrase or rewrite the author's wording unless the task explicitly requires it
• Do NOT add headings that editorialize (e.g. "Amazing Discovery"); use neutral descriptive headings
• Do NOT over-format: not every sentence needs bold, and not every paragraph needs a heading

Formatting principles — what TO do

• Preserve the author's voice, tone, and wording as much as possible
• Bold key conclusions and core takeaways — the sentences a reader would likely highlight
• Extract parallel items from prose into lists when the structure is clearly present
• Add headings where the topic genuinely shifts
• Use tables for comparisons or structured data buried in prose
• Use blockquotes for golden quotes, memorable statements, or important warnings
• Fix obvious typos only when the correction is unambiguous

---

Step 5: Save Formatted File

Save the formatted content as a new file. The output filename is built from the original filename plus a suffix defined in EXTEND.md.

• Default suffix: _formatted → {original-filename}_formatted.md
• Override via EXTEND.md: set output_suffix: _formatted → {original-filename}_formatted.md

Backup existing file before overwrite:

if [ -f "{filename}_formatted.md" ]; then
  mv "{filename}_formatted.md" "{filename}_formatted.backup-$(date +%Y%m%d-%H%M%S).md"
fi

After Step 5 saves the formatted file, Step 6 must run on that saved output file in-place.

---

Step 6: Execute Structural Rendering Compatibility Script

Scripts are stored in the scripts/ subdirectory. ${SKILL_DIR} is the root directory containing this SKILL.md.

This script is designed for MkDocs + Material rendering compatibility. It fixes structural spacing around math, list, and table blocks while preserving document content.

Runtime Requirements

• Node.js 18+
• Local npm dependencies installed once in ${SKILL_DIR}

If dependencies are not installed yet:

cd ${SKILL_DIR}
npm install

If package-lock.json already exists, prefer:

cd ${SKILL_DIR}
npm ci

Script

Script	Purpose
scripts/format-structure.mjs	Fixes mkdocs/material-sensitive spacing around math/list/table blocks

Command

node ${SKILL_DIR}/scripts/format-structure.mjs <file.md> [options]

CLI Options

Option	Short	Description	Default
--output	-o	Specify output file path	In-place
--dry-run	-n	Preview changes without writing	false
--no-backup		Skip backup of existing output file	false

What the script fixes

1. Math block spacing

   • Ensures block math has blank lines before and after
   • Handles standalone single-line block math such as $$E = mc^2$$
   • Removes illegal inner blank lines immediately after opening $$ or before closing $$

2. List block spacing

   • Ensures blank lines before and after markdown lists

3. Table block spacing

   • Ensures blank lines before and after markdown tables

4. Safety

   • Uses Markdown AST to detect structural blocks
   • Applies minimal text patches instead of re-stringifying the full document
   • Preserves text content and existing writing style as much as possible

EXTEND.md Rule Toggles

The script reads simple key: value settings from EXTEND.md.

Supported keys:

output_suffix: \_formatted
fix_math_blocks: true
fix_list_blocks: true
fix_table_blocks: true
trim_math_inner_blank_lines: true

Usage in Workflow

• Full workflow: after Step 5 saves the formatted file, run the script in-place on that output file.
• Structural-fixes-only mode: run the script directly on the original file in-place.

Examples:

# In-place fix on already formatted output
node ${SKILL_DIR}/scripts/format-structure.mjs "{output-file-path}"

# Write to a custom file
node ${SKILL_DIR}/scripts/format-structure.mjs article.md -o article_fixed.md

# Preview only
node ${SKILL_DIR}/scripts/format-structure.mjs article.md --dry-run

# Skip backup
node ${SKILL_DIR}/scripts/format-structure.mjs article.md --no-backup

Output and Backup Behavior

Condition	Output Path
Default	Input file modified in-place
With --output custom.md	custom.md
Step 5 + default suffix	{original-name}_formatted.md
With output_suffix: _formatted in EXTEND.md	{original-name}_formatted.md

If the target output file already exists and --no-backup is not set, the script creates a timestamped backup before writing.

---

📋 Step 7: Completion Report

**Formatting Complete**

**Files:**
- Analysis: {filename}-analysis.md
- Formatted: {filename}_formatted.md

**Content Analysis Summary:**
- Highlights found: X key insights
- Golden quotes: X memorable sentences
- Formatting issues fixed: X items

**Changes Applied:**
- Frontmatter: [added/updated] (title, slug, summary)
- Headings added: X (##: N, ###: N)
- Bold markers added: X
- Lists created: X (from prose → list conversion)
- Tables created: X
- Admonitions added: X
- Typos fixed: X [list each: "original" → "corrected"]

**Structural Compatibility Script:**
- Math blocks processed: X
- List blocks processed: X
- Table blocks processed: X
- Empty lines added: X
- Math inner blank lines removed: X
- Backup created: [yes/no]