---
name: content-signals
description: Use the Content-Signal directive in robots.txt for AI usage preferences
---

# Content Signals in robots.txt

Add a `Content-Signal:` directive to `/robots.txt` declaring how AI/agent systems may use your content.

## Requirements

- Add at least one `Content-Signal:` line at robots.txt root or under a `User-agent` block
- Express preferences for: `search`, `ai-input`, `ai-train`
- Each signal value is `yes` or `no`

## Example

```
User-agent: *
Allow: /
Content-Signal: search=yes, ai-input=yes, ai-train=no
```

| Signal | Meaning |
|---|---|
| `search=yes\|no` | May this content appear in search results |
| `ai-input=yes\|no` | May this content be used as input to AI answers (RAG, summarization) |
| `ai-train=yes\|no` | May this content be used to train AI models |

## References

- [IETF draft — AI Preferences: Content Signals](https://datatracker.ietf.org/doc/draft-romm-aipref-contentsignals/) (spec)
- [contentsignals.org](https://contentsignals.org/) (proposal)