Guide · Agent skill
How to use the External Links Audit agent skill
Updated · written with AI from the project's own documentation and checked against our catalogue data
The External Links Audit is an agent skill that tells an AI agent how to review a web page's outbound links. It checks whether factual claims are backed by authoritative sources, whether external links carry rel="noopener noreferrer", and whether paid or affiliate links are marked correctly. This guide explains what agent skills are, how to install this one, how to ask for an audit in plain language, and where its limits are.
External Links Auditthedaviddias/Front-End-Checklist · MIT Download the skill Quick start
- 1Download the ZIP. Get the external-links skill ZIP from its page on the directory.
- 2Unzip into a skills folder. Extract it into ~/.claude/skills/ for personal use or into a project's .claude/skills/ folder.
- 3Or upload in the Claude apps. Go to Settings → Capabilities → Skills and upload the ZIP.
- 4Send a plain request. Describe the page and the task, such as checking citations or link attributes.
- 5Review the findings. Read the flagged links and suggested sources, then verify each source before editing.
- 6Apply the fixes. Add rel="noopener noreferrer", sponsored or nofollow attributes, and source links where the audit recommends them.
What is an agent skill and what does this one do?
An agent skill is a folder of instructions that an AI agent can load when a task matches the skill's description. This skill lives in the skills/external-links folder of the Front-End-Checklist project and is licensed under MIT. Its main file is SKILL.md, and it also includes references/rule.md with fuller details.
When the skill is active, the agent checks a page's outbound links. It looks at three things: whether factual claims are supported by links to authoritative sources such as government sites, peer-reviewed research or official documentation; whether external links have rel="noopener noreferrer"; and whether paid or sponsored links are marked rel="sponsored" or rel="nofollow". The agent can also suggest where to add a source link and show an example rewrite.
How to install the External Links skill
You can install the skill in one of three ways. For a personal setup, download the ZIP from the skill's page on our directory and unzip it into ~/.claude/skills/. For a single project, unzip it into that project's .claude/skills/ folder. You can also upload the ZIP in the Claude apps under Settings → Capabilities → Skills.
- Personal install: unzip into ~/.claude/skills/
- Project install: unzip into the project's .claude/skills/ folder
- Claude apps: Settings → Capabilities → Skills, then upload the ZIP
How to trigger the skill with natural requests
You do not need a special command. The skill is meant to activate when your request matches its description, so describe the task in plain words. The skill's description names three situations: auditing content pages for citation quality, suggesting authoritative sources for factual claims, and reviewing whether a page's external link attributes such as nofollow and noopener are set correctly.
- Check whether the claims in this article are backed by credible sources.
- Review the external links on this landing page for noopener and noreferrer.
- Find places in this blog post where a source link should be added.
- Check that our affiliate links are marked sponsored or nofollow.
What to expect from an audit
For each content page, the agent counts external links, meaning links to domains other than the current site. It then checks each external link's attributes and flags problems. The skill's Fix steps ask the agent to find statistics, research or expert claims without a source, locate an appropriate authoritative source, add an inline link, and add rel="sponsored" to paid or affiliate links and rel="nofollow" to links you cannot vouch for.
The skill also gives a rewrite pattern. For example, a sentence stating that studies show 60% of users abandon slow pages can be rewritten to name a source, such as Google's web.dev research, and link to it with rel="noopener noreferrer". The agent should still verify that any source it suggests actually supports the claim.
- Flags external links missing rel="noopener noreferrer"
- Flags paid or affiliate links missing rel="sponsored"
- Flags long-form pages (over 500 words) with factual claims but zero external links
- Suggests avoiding links to competitors' main commercial pages
<a href="https://web.dev/performance/" rel="noopener noreferrer">Google's web.dev research</a>Requirements, scripts and network safety
The skill lists no required tools. It does not run scripts and does not use the network. Its guidance comes from SEO best practices written in the skill's text, not from live data, so the agent does not fetch current search documentation or check the sources it recommends.
Because the skill is text-only, it cannot confirm that a link is still live or that a source says what the page claims. Read suggested sources yourself before publishing.
Tips for getting useful results
Give the agent the page's HTML or the full text with its links, since the audit depends on the actual link markup. Ask for one page at a time for the most detailed review. Use the skill for the narrow checks it covers, and use other tools for broader security or SEO work.
- Paste the full HTML of the page when checking attributes
- Ask the agent to list each suggested source so you can verify it
- Treat the skill's SEO statements as general guidance, not verified facts
What people use it for
- Checking that a blog article links to sources for its statistics
- Reviewing HTML link attributes on a landing page before release
- Auditing affiliate links on a review page for sponsored or nofollow markup
- Finding long-form pages that make factual claims but cite nothing
Frequently asked questions
How do I install the external-links agent skill?
Download the ZIP from the skill's page, then unzip it into ~/.claude/skills/ for personal use or into a project's .claude/skills/ folder. In the Claude apps you can instead upload the ZIP under Settings → Capabilities → Skills.
Does the external links skill cost money or require a licence?
The skill is listed under the MIT licence. The source does not mention prices, so check the directory page for any terms before you use it.
What does the external links skill require?
The skill lists no required dependencies. It does not run scripts and does not use the network, so it works as text instructions for the agent.
Why does the skill check for rel="noopener noreferrer"?
The skill's guidance says to add rel="noopener noreferrer" to external links for security. It is one of three checks the audit performs, along with source support for claims and sponsored or nofollow markup on paid links.
Does the skill check whether the sources it suggests are real or current?
No. The guidance is based on SEO best practices written in the skill's text and is not checked against live data. You should open and verify every suggested source yourself.
Is this skill a replacement for a full SEO or security audit?
No. It covers only the narrow link checks described above. For broader link safety or SEO work, use dedicated tools and reviews.
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Our verdict
This skill suits website owners, content writers, front-end developers and marketers who want a quick, text-based check of citations and link attributes on a page. It is a poor choice if you need verified SEO claims, live source checking, or a thorough security review of links beyond the noopener and noreferrer attributes.
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