audit website for SEO, security, performance and 200+ other issues

Website Audit Skill

Audit websites for SEO, technical, content, performance and security issues using the squirrelscan cli.

squirrelscan provides a cli tool squirrel - available for macos, windows and linux. It carries out extensive website auditing by emulating a browser, search crawler, and analyzing the website's structure and content against over 230+ rules.

It will provide you a list of issues as well as suggestions on how to fix them.

Links

* squirrelscan website is at https://squirrelscan.com * documentation (including rule references) are at docs.squirrelscan.com

You can look up the docs for any rule with this template:

https://docs.squirrelscan.com/rules/{rule_category}/{rule_id}

example:

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:

and more

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

When to Use

Use this skill when you need to:

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:

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:

1. Run the audit (saves to database, shows console output) 2. 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  --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  --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:

1. Present the report - show the user the audit results and score 2. Propose fixes - list the issues you can fix and ask the user to confirm before making changes 3. Parallelize approved fixes - use subagents for bulk content edits (alt text, headings, descriptions) 4. Iterate - fix batch → re-audit → present results → propose next batch 5. Pause for judgment - broken links, structural changes, and anything ambiguous should be flagged for user review 6. Show before/after - present score comparison after each fix batch

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:

Parallelizing Fixes with Subagents

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

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 | -f | Output format: console, text, json, html, markdown, llm | console | | --coverage | -C | Coverage mode: quick, surface, full | surface | | --max-pages | -m | Maximum pages to crawl (max 5000) | varies by coverage | | --output | -o | 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 | -n | 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:

Report Command Options

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

Config Subcommands

| Command | Description | |---------|-------------| | config show | Show current config | | config set | 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  --format llm

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

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: 1. Install squirrel: squirrelscan.com/download 2. Ensure ~/.local/bin is in PATH 3. 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

1. Crawl: Discovers and fetches pages starting from the base URL 2. Analyze: Runs audit rules on each page 3. External Links: Checks external links for availability 4. 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

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

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

squirrel command not found

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

Solution: 1. Install squirrel: squirrelscan.com/download 2. Ensure ~/.local/bin is in PATH 3. 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