---
title: "AIPREF training signal: definition | Agent Ready Crawlers"
description: "AIPREF training signal: An IETF AI Preferences vocabulary for usage preferences. The robots.txt builder on this site does not write it."
canonical: https://agentreadycrawlers.com/glossary/aipref-training-signal
site: "Agent Ready Crawlers"
last_updated: 2026-11-04
section: "Glossary"
---

# AIPREF training signal: definition | Agent Ready Crawlers

> AIPREF training signal: An IETF AI Preferences vocabulary for usage preferences. The robots.txt builder on this site does not write it.

Source: https://agentreadycrawlers.com/glossary/aipref-training-signal
Site: Agent Ready Crawlers
Last reviewed: 2026-11-04

Glossary

# AIPREF training signal

In short

An IETF AI Preferences vocabulary for usage preferences. Google says it intends to read the training preference written as a user-agent line, \_\_usage\_ai-training, in early 2027. The robots.txt builder on this site does not write it. Related: What Content-Signals changes and Google-Extended profile.

## Definition

An IETF AI Preferences vocabulary for usage preferences. Google says it intends to read the training preference written as a user-agent line, \_\_usage\_ai-training, in early 2027.

## Sourced example

twitter.com's robots.txt already names \_\_usage\_ai-training (shared crawl, 2026-11-04); Google plans support in early 2027. [Source](https://developers.google.com/search/docs/crawling-indexing/google-common-crawlers), read 2026-11-04.

## How it shows up here

The robots.txt builder on this site does not write it.

-   [What Content-Signals changes](https://agentreadycrawlers.com/guides/what-content-signals-change/)
-   [Google-Extended profile](https://agentreadycrawlers.com/crawlers/google-extended/)

Previous: [ai-input](https://agentreadycrawlers.com/glossary/ai-input/). Next: [Applebot-Extended](https://agentreadycrawlers.com/glossary/applebot-extended/). [All 41 terms](https://agentreadycrawlers.com/glossary/).

## Sources

-   [Google common crawlers](https://developers.google.com/search/docs/crawling-indexing/google-common-crawlers) read 2026-11-04

Last reviewed 2026-11-04