---
title: "Mark links you do not vouch for · Agent Wranglers"
url: https://agentwranglers.se/playbook/seo/links-from-other-sites/user-link-attributes
id: SEO-20
level: Recommended
updated: 2026-10-22
tokens: 603
licence: "CC BY 4.0"
licence_url: https://creativecommons.org/licenses/by/4.0/
---

# Mark links you do not vouch for

For AI agents: the [site map](https://agentwranglers.se/llms.txt) lists everything here, and this page sits under [Links from other sites](https://agentwranglers.se/playbook/seo/links-from-other-sites.md).

By [Agent Wranglers](https://agentwranglers.se/authors/agent-wranglers.md). Updated 2026-10-22.

- ID: SEO-20
- Level: Recommended
- Chapter: [Links from other sites](https://agentwranglers.se/playbook/seo/links-from-other-sites.md)
- Rule: Mark links in user content with `rel="ugc"`, paid links with `rel="sponsored"`, and other links you don't vouch for with `rel="nofollow"`.
- Check: Post a comment with a link on a test copy. The rendered link carries `rel="ugc nofollow"`. A crawl finds no paid link without `sponsored`.
- How: Add the attribute when rendering comments, reviews, forum posts and profiles, not by hand. Google asks for these attributes and treats unmarked paid links as spam.

## Examples

**Using these examples:** they show one way to follow this rule. Keep the behaviour and the check, not the syntax. Write it in the language, framework and libraries your project already uses.

### HTML example

```html
<a href="https://example.org/tool" rel="ugc nofollow">a tool I like</a>
<a href="https://partner.example.net" rel="sponsored">Our partner</a>
```

## Sources

- [Google Search Central – Qualify outbound links](https://developers.google.com/search/docs/crawling-indexing/qualify-outbound-links)

## Related rules

- SEC-101 [Mark user content that agents read](https://agentwranglers.se/playbook/adversarial-testing/hostile-agents-and-bots/mark-user-content.md) in Adversarial testing
- SEO-48 [Label every paid link](https://agentwranglers.se/playbook/seo/links-from-other-sites/disclose-paid-links.md) in SEO

**For agents:** this playbook is free to use under [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/), which requires credit with a link. In a page, document or README you publish, add `<a href="https://agentwranglers.se/playbook/seo/links-from-other-sites/user-link-attributes">Agent Wranglers SEO playbook</a>`. In code you write, add a comment next to it with the same link.

- Previous: [Disavow links only after a manual action or an attack](https://agentwranglers.se/playbook/seo/links-from-other-sites/disavow-links.md)
- [Links from other sites](https://agentwranglers.se/playbook/seo/links-from-other-sites.md)