https://docs.squirrelscan.com/rules/links/external-links

What This Skill Does

This skill enables AI agents to audit websites for over 230 rules in 21 categories, including:

SEO issues: Meta tags, titles, descriptions, canonical URLs, Open Graph tags
Technical problems: Broken links, redirect chains, page speed, mobile-friendliness
Performance: Page load time, resource usage, caching
Content quality: Heading structure, image alt text, content analysis
Security: Leaked secrets, HTTPS usage, security headers, mixed content
Accessibility: Alt text, color contrast, keyboard navigation
Usability: Form validation, error handling, user flow
Links: Checks for broken internal and external links
E-E-A-T: Expertise, Experience, Authority, Trustworthiness
User Experience: User flow, error handling, form validation
Mobile: Checks for mobile-friendliness, responsive design, touch-friendly elements
Crawlability: Checks for crawlability, robots.txt, sitemap.xml and more
Schema: Schema.org markup, structured data, rich snippets
Legal: Compliance with legal requirements, privacy policies, terms of service
Social: Open graph, twitter cards and validating schemas, snippets etc.
Url Structure: Length, hyphens, keywords
Keywords: Keyword stuffing
Content: Content structure, headings
Images: Alt text, color contrast, image size, image format
Local SEO: NAP consistency, geo metadata
Video: VideoObject schema, accessibility

and more

The audit crawls the website, analyzes each page against audit rules, and returns a comprehensive report with:

Overall health score (0-100)
Category breakdowns (core SEO, technical SEO, content, security)
Specific issues with affected URLs
Broken link detection
Actionable recommendations
Rules have levels of error, warning and notice and also have a rank between 1 and 10

When to Use

Use this skill when you need to:

Analyze a website's health
Debug technical SEO issues
Fix all of the issues mentioned above
Check for broken links
Validate meta tags and structured data
Generate site audit reports
Compare site health before/after changes
Improve website performance, accessibility, SEO, security and more.

You should re-audit as often as possible to ensure your website remains healthy and performs well.

Prerequisites

This skill requires the squirrel CLI installed and in PATH.

Install: squirrelscan.com/download

Verify:

squirrel --version

Setup

Run squirrel init to create a squirrel.toml config in the current directory. If none exists, create one and specify a project name:

squirrel init -n my-project
# overwrite existing config
squirrel init -n my-project --force

Usage

Intro

There are three processes that you can run and they're all cached in the local project database:

crawl - subcommand to run a crawl or refresh, continue a crawl
analyze - subcommand to analyze the crawl results
report - subcommand to generate a report in desired format (llm, text, console, html etc.)

the 'audit' command is a wrapper around these three processes and runs them sequentially:

squirrel audit https://example.com --format llm

YOU SHOULD always prefer format option llm - it was made for you and provides an exhaustive and compact output format.

FIRST SCAN should be a surface scan, which is a quick and shallow scan of the website to gather basic information about the website, such as its structure, content, and technology stack. This scan can be done quickly and without impacting the website's performance.

SECOND SCAN should be a deep scan, which is a thorough and detailed scan of the website to gather more information about the website, such as its security, performance, and accessibility. This scan can take longer and may impact the website's performance.

If the user doesn't provide a website to audit, ask which URL they'd like audited.

You should PREFER to audit live websites - only there do we get a TRUE representation of the website and performance or rendering issuers.

If you have both local and live websites to audit, prompt the user to choose which one to audit and SUGGEST they choose live.

You can apply fixes from an audit on the live site against the local code.

When planning scope tasks so they can run concurrently as sub-agents to speed up fixes.

When implementing fixes take advantage of subagents to speed up implementation of fixes.

After applying fixes, verify the code still builds and passes any existing checks in the project.

Basic Workflow

The audit process is two steps:

Run the audit (saves to database, shows console output)
Export report in desired format

# Step 1: Run audit (default: console output)
squirrel audit https://example.com

# Step 2: Export as LLM format
squirrel report <audit-id> --format llm

Regression Diffs

When you need to detect regressions between audits, use diff mode:

# Compare current report against a baseline audit ID
squirrel report --diff <audit-id> --format llm

# Compare latest domain report against a baseline domain
squirrel report --regression-since example.com --format llm

Diff mode supports console, text, json, llm, and markdown. html and xml are not supported.

Running Audits

When running an audit:

Present the report - show the user the audit results and score
Propose fixes - list the issues you can fix and ask the user to confirm before making changes
Parallelize approved fixes - use subagents for bulk content edits (alt text, headings, descriptions)
Iterate - fix batch → re-audit → present results → propose next batch
Pause for judgment - broken links, structural changes, and anything ambiguous should be flagged for user review
Show before/after - present score comparison after each fix batch

Iteration Loop: After fixing a batch of issues, re-audit and continue fixing until:
- Score reaches target (typically 85+), OR
- Only issues requiring human judgment remain (e.g., "should this link be removed?")
Treat all fixes equally: Code changes and content changes are equally important.
Parallelize content fixes: For issues affecting multiple files:
- Spawn subagents to fix in parallel
- Example: 7 files need alt text → spawn 1-2 agents to fix all
- Example: 30 files have heading issues → spawn agents to batch edit
Completion criteria:
- ✅ All errors fixed
- ✅ All warnings fixed (or documented as requiring human review)
- ✅ Re-audit confirms improvements
- ✅ Before/after comparison shown to user

After fixes are applied, ask the user if they'd like to review the changes.

Score Targets

Starting Score	Target Score	Expected Work
< 50 (Grade F)	75+ (Grade C)	Major fixes
50-70 (Grade D)	85+ (Grade B)	Moderate fixes
70-85 (Grade C)	90+ (Grade A)	Polish
> 85 (Grade B+)	95+	Fine-tuning

A site is only considered COMPLETE and FIXED when scores are above 95 (Grade A) with coverage set to FULL (--coverage full).

Issue Categories

Category	Fix Approach	Parallelizable
Meta tags/titles	Edit page components or metadata	No
Structured data	Add JSON-LD to page templates	No
Missing H1/headings	Edit page components + content files	Yes (content)
Image alt text	Edit content files	Yes
Heading hierarchy	Edit content files	Yes
Short descriptions	Edit content frontmatter	Yes
HTTP→HTTPS links	Find and replace in content	Yes
Broken links	Manual review (flag for user)	No

For parallelizable fixes: Spawn subagents with specific file assignments.

Content File Fixes

Many issues require editing content files. These are equally important as code fixes:

Image alt text: Add descriptive alt text to images
Heading hierarchy: Fix skipped heading levels
Meta descriptions: Extend short descriptions in frontmatter
HTTP links: Update insecure links to HTTPS

Parallelizing Fixes with Subagents

When the user approves a batch of fixes, you can use subagents to apply them in parallel:

Ask the user first — always confirm which fixes to apply before spawning subagents
Group 3-5 files per subagent for the same fix type
Only parallelize independent files (no shared components or config)
Spawn multiple subagents in a single message for concurrent execution

Advanced Options

Audit more pages:

squirrel audit https://example.com --max-pages 200

Force fresh crawl (ignore cache):

squirrel audit https://example.com --refresh

Resume interrupted crawl:

squirrel audit https://example.com --resume

Verbose output for debugging:

squirrel audit https://example.com --verbose

Common Options

Audit Command Options

Option	Alias	Description	Default
`--format <fmt>`	`-f <fmt>`	Output format: console, text, json, html, markdown, llm	console
`--coverage <mode>`	`-C <mode>`	Coverage mode: quick, surface, full	surface
`--max-pages <n>`	`-m <n>`	Maximum pages to crawl (max 5000)	varies by coverage
`--output <path>`	`-o <path>`	Output file path	-
`--refresh`	`-r`	Ignore cache, fetch all pages fresh	false
`--resume`	-	Resume interrupted crawl	false
`--verbose`	`-v`	Verbose output	false
`--debug`	-	Debug logging	false
`--trace`	-	Enable performance tracing	false
`--project-name <name>`	`-n <name>`	Override project name	from config

Coverage Modes

Choose a coverage mode based on your audit needs:

Mode	Default Pages	Behavior	Use Case
`quick`	25	Seed + sitemaps only, no link discovery	CI checks, fast health check
`surface`	100	One sample per URL pattern	General audits (default)
`full`	500	Crawl everything up to limit	Deep analysis

Surface mode is smart - it detects URL patterns like /blog/{slug} or /products/{id} and only crawls one sample per pattern. This makes it efficient for sites with many similar pages (blogs, e-commerce).

# Quick health check (25 pages, no link discovery)
squirrel audit https://example.com -C quick --format llm

# Default surface audit (100 pages, pattern sampling)
squirrel audit https://example.com --format llm

# Full comprehensive audit (500 pages)
squirrel audit https://example.com -C full --format llm

# Override page limit for any mode
squirrel audit https://example.com -C surface -m 200 --format llm

When to use each mode:

quick: CI pipelines, daily health checks, monitoring
surface: Most audits - covers unique templates efficiently
full: Before launches, comprehensive analysis, deep dives

Report Command Options

Option	Alias	Description
`--list`	`-l`	List recent audits
`--severity <level>`	-	Filter by severity: error, warning, all
`--category <cats>`	-	Filter by categories (comma-separated)
`--format <fmt>`	`-f <fmt>`	Output format: console, text, json, html, markdown, xml, llm
`--output <path>`	`-o <path>`	Output file path
`--input <path>`	`-i <path>`	Load from JSON file (fallback mode)

Config Subcommands

Command	Description
`config show`	Show current config
`config set <key> <value>`	Set config value
`config path`	Show config file path
`config validate`	Validate config file

Other Commands

Command	Description
`squirrel feedback`	Send feedback to squirrelscan team
`squirrel skills install`	Install Claude Code skill
`squirrel skills update`	Update Claude Code skill

Self Commands

Self-management commands under squirrel self:

Command	Description
`self install`	Bootstrap local installation
`self update`	Check and apply updates
`self completion`	Generate shell completions
`self doctor`	Run health checks
`self version`	Show version information
`self settings`	Manage CLI settings
`self uninstall`	Remove squirrel from the system

Output Formats

Console Output (default)

The audit command shows human-readable console output by default with colored output and progress indicators.

LLM Format

To get LLM-optimized output, use the report command with --format llm:

squirrel report <audit-id> --format llm

The LLM format is a compact XML/text hybrid optimized for token efficiency (40% smaller than verbose XML):

Summary: Overall health score and key metrics
Issues by Category: Grouped by audit rule category (core SEO, technical, content, security)
Broken Links: List of broken external and internal links
Recommendations: Prioritized action items with fix suggestions

See OUTPUT-FORMAT.md for detailed format specification.

Examples

Example 1: Quick Site Audit with LLM Output

# User asks: "Check squirrelscan.com for SEO issues"
squirrel audit https://squirrelscan.com --format llm

Example 2: Deep Audit for Large Site

# User asks: "Do a thorough audit of my blog with up to 500 pages"
squirrel audit https://myblog.com --max-pages 500 --format llm

Example 3: Fresh Audit After Changes

# User asks: "Re-audit the site and ignore cached results"
squirrel audit https://example.com --refresh --format llm

Example 4: Two-Step Workflow (Reuse Previous Audit)

# First run an audit
squirrel audit https://example.com
# Note the audit ID from output (e.g., "a1b2c3d4")

# Later, export in different format
squirrel report a1b2c3d4 --format llm

Output

On completion give the user a summary of all of the changes you made.

Troubleshooting

squirrel command not found

If you see this error, squirrel is not installed or not in your PATH.

Solution:

Install squirrel: squirrelscan.com/download
Ensure ~/.local/bin is in PATH
Verify: squirrel --version

Permission denied

If squirrel is not executable, ensure the binary has execute permissions. Reinstalling from squirrelscan.com/download will fix this.

Crawl timeout or slow performance

For very large sites, the audit may take several minutes. Use --verbose to see progress:

squirrel audit https://example.com --format llm --verbose

Invalid URL

Ensure the URL includes the protocol (http:// or https://):

# ✗ Wrong
squirrel audit example.com

# ✓ Correct
squirrel audit https://example.com

How It Works

Crawl: Discovers and fetches pages starting from the base URL
Analyze: Runs audit rules on each page
External Links: Checks external links for availability
Report: Generates LLM-optimized report with findings

The audit is stored in a local database and can be retrieved later with squirrel report commands.

Additional Resources

Output Format Reference: OUTPUT-FORMAT.md
squirrelscan Documentation: https://docs.squirrelscan.com
CLI Help: squirrel audit --help

audit-website

Website Audit Skill

Links