---
title: "Meta-ExternalFetcher: user agent and token | Agent Ready Crawlers"
description: "Meta-ExternalFetcher from Meta: exact user-agent string, robots.txt token meta-externalfetcher, live answer fetch purpose and how to verify it."
canonical: https://agentreadycrawlers.com/crawlers/meta-externalfetcher
site: "Agent Ready Crawlers"
last_updated: 2026-11-04
section: "Crawlers"
---

# Meta-ExternalFetcher: user agent and token | Agent Ready Crawlers

> Meta-ExternalFetcher from Meta: exact user-agent string, robots.txt token meta-externalfetcher, live answer fetch purpose and how to verify it.

Source: https://agentreadycrawlers.com/crawlers/meta-externalfetcher
Site: Agent Ready Crawlers
Last reviewed: 2026-11-04

Live answer fetcher from Meta

# Meta-ExternalFetcher

In short

Meta-ExternalFetcher is Meta's live answer fetcher. The operator publishes nothing a site can check. 8.5 percent of 5,938 top-10,000 sites with a parsed robots.txt disallow it at the root (crawl of 2026-11-04). Its user-agent entry: meta-externalfetcher/1.1 (+https://developers.facebook.com/docs/sharing/webmasters/web-crawlers). Meta-ExternalFetcher may bypass robots.txt because it performs fetches requested by the user.

Operator

[Meta](https://agentreadycrawlers.com/crawlers/operator/meta/) Vendor profile: [Meta](https://agentreadycrawlers.com/vendors/meta/)

Purpose

Live answer fetch [All live answer fetch rows](https://agentreadycrawlers.com/crawlers/purpose/live-answer-fetch/). Fetches a page because a person asked an assistant about it, one request at a time.

User-agent string

`meta-externalfetcher/1.1 (+https://developers.facebook.com/docs/sharing/webmasters/web-crawlers)`

robots.txt token

`meta-externalfetcher` Matched case-insensitively (RFC 9309). The token and the user-agent string are different things.

Respects robots.txt

May not apply (user-triggered)

Meta: may bypass robots.txt because it performs fetches requested by the user. [Source](https://developers.facebook.com/docs/sharing/webmasters/web-crawlers/), read 2026-11-04.

Verification

Nothing published

The operator publishes no list, reverse DNS pattern or key directory a site owner can check. [Documentation](https://developers.facebook.com/docs/sharing/webmasters/web-crawlers/), read 2026-11-04.

IP ranges

Not published.

Rate behaviour

User-triggered.

Block rate

**8.5%** of 5,938 top-10,000 sites with a parsed robots.txt disallow `Meta-ExternalFetcher` at the root (505 sites). 4.7% name it; 3.8% refuse it only through a \* group. Rank 22 of 31 tokens measured.

Across all 8,624 parsed robots.txt files in the crawl: 6.0% (3.3% named). Crawl of 2026-11-04; [report](https://agentreadycrawlers.com/block-rates/).

Documentation

[developers.facebook.com](https://developers.facebook.com/docs/sharing/webmasters/web-crawlers/), read 2026-11-04.

Note. Meta says it supports evaluating and improving agentic AI capabilities, including helping AI navigate websites to complete tasks.

## Allow and refuse lines

### To allow meta-externalfetcher

User-agent: meta-externalfetcher
Allow: /

### To refuse meta-externalfetcher

User-agent: meta-externalfetcher
Disallow: /

Refusing or allowing in robots.txt states a preference. For this row the operator or its documentation says robots.txt may not govern the fetch, so enforcement belongs in your WAF.

## Meta in the Verification Ledger

User agent strings only; the page recommends IP allowlisting but links no list. Publishes nothing for Muse. [All operators](https://agentreadycrawlers.com/verification/).

IP lists

publishes nothing

Reverse DNS

publishes nothing

Key directory

publishes nothing

Cloudflare

not checked

Visa TAP registry

no public operator-level registration found (checked 2026-11-04)

Mastercard Agent Pay

no public operator-level registration found (checked 2026-11-04)

## Other Meta rows

-   [Meta-ExternalAgent](https://agentreadycrawlers.com/crawlers/meta-externalagent/) Training token meta-externalagent
-   [Meta-WebIndexer](https://agentreadycrawlers.com/crawlers/meta-webindexer/) Search index token meta-webindexer
-   [Meta-ExternalAds](https://agentreadycrawlers.com/crawlers/meta-externalads/) Other token meta-externalads
-   [FacebookExternalHit](https://agentreadycrawlers.com/crawlers/facebookexternalhit/) Other token facebookexternalhit
-   [FacebookBot (legacy token)](https://agentreadycrawlers.com/crawlers/facebookbot/) Other token FacebookBot
-   [Muse (personal agent)](https://agentreadycrawlers.com/crawlers/meta-muse/) Shopping agent no token

## Sources

-   [Meta Web Crawlers](https://developers.facebook.com/docs/sharing/webmasters/web-crawlers/) read 2026-11-04

Last reviewed 2026-11-04