# rel="service-doc" Explained

The service-doc relation can expose machine-readable documentation through HTTP headers.

Canonical URL: https://truborankai.com/blog/rel-service-doc-explained

Author: TruboRankAI
Published: April 30, 2026
Updated: July 18, 2026

## Quick Answer

rel="service-doc" is a Link relation that can point clients to documentation or guidance resources for a service or website.

## AI Summary

Using rel="service-doc" in Link headers can help crawlers discover llms.txt, documentation, or AI guidance resources earlier in the fetch process.

## Main Explanation

HTTP Link headers are sent before the HTML body is parsed. That makes them useful for discovery infrastructure.

For AI-focused websites, service-doc can point to llms.txt or related documentation.

## Practical Steps

1. Choose a public documentation URL.
2. Add a Link header with rel="service-doc".
3. Include the correct content type.
4. Test with curl -I.

## FAQ

### Is service-doc required?

No. It is an optional discovery signal.

### Can it point to llms.txt?

Yes, if that is your service documentation resource.

### How do I test it?

Run curl -I https://example.com and inspect Link headers.

## Editorial Methodology

TruboRankAI publishes practical guidance from observable website signals, reproducible checks, and cited primary or first-party references when platform behavior or measured claims can change. Crawler access, indexing, search visibility, mentions, citations, referral visits, and conversions are treated as separate signals. Readers should verify time-sensitive settings and policies against the linked official documentation.

## Related Internal Links

- [Link Headers Checker](/link-headers-checker)
- [llms.txt Checker](/llms-txt-checker)
- [Markdown Negotiation Checker](/markdown-negotiation-checker)
- [Pricing](/pricing)