# Meta-ExternalFetcher

Category: [AI Bots & Crawlers](https://seo-geo-glossary.com/en/glossary/category/ai-bots-crawlers/) › [Other AI bots](https://seo-geo-glossary.com/en/glossary/category/ai-bots-crawlers/other-ai-bots/) · Also known as: meta-externalfetcher

**Meta-ExternalFetcher** is a Meta user agent that fetches individual links when a user asks for them. Meta says it supports agentic AI features, such as an AI navigating a website to complete a task for someone, and states that it may bypass robots.txt rules.

## How is it different from other Meta bots?

Meta lists its crawlers on a single documentation page. Meta-ExternalAgent crawls for training foundation models and for indexing content, and Meta-WebIndexer crawls to improve search results in Meta AI. Both run systematically and can be controlled in robots.txt. The ExternalFetcher only loads a page at the moment a person's request needs it, which makes it a user-triggered fetcher similar to those other AI providers run.

As a result, a `Disallow` rule keeps Meta's training and search crawlers out, while Meta does not commit to the ExternalFetcher following it. Blocking those requests reliably takes a rule at the server or CDN level (assessment).

## Example

A request in the access log carries this user agent:

```
meta-externalfetcher/1.1
```

Meta also lists a longer variant that adds a link to its crawler documentation. Some third-party bot directories describe the fetcher as robots.txt-compliant or as verifiable through signed requests. Meta's documentation says the opposite about robots.txt and does not mention signing. A single hit on a product page shortly after someone asked Meta AI about that product fits this fetcher. Large, systematic crawls of many URLs point to one of the crawlers instead (assessment).

## Common mistakes

- **Treating `Disallow` as a block.** Meta writes that the fetcher may bypass robots.txt because it performs fetches requested by a user.
- **Expecting changes right away.** For robots.txt changes, Meta's documentation allows up to 24 hours.

## FAQ

**Does Meta-ExternalFetcher respect robots.txt?**
Not necessarily. Meta says it may bypass robots.txt rules because it acts on a user's request.

**Is it used to train AI models?**
Meta does not describe it that way. Model training is the stated purpose of Meta-ExternalAgent.

## At a glance

- **Operator:** Meta Platforms
- **Purpose:** fetches individual links at a user's request (per Meta)
- **robots.txt token:** meta-externalfetcher
- **User agent:** meta-externalfetcher/1.1
- **Respects robots.txt:** may bypass robots.txt, says Meta
- **Docs:** [Meta Web Crawlers](https://developers.facebook.com/docs/sharing/webmasters/web-crawlers/)

Last checked: October 8, 2026

## AI bots compared

| Bot | Operator | Purpose | robots.txt token | robots.txt according to the operator | IP list published? |
|---|---|---|---|---|---|
| Google-Extended | Google | Controls Gemini training and grounding (no crawler of its own) | Google-Extended | robots.txt token only; fetching is done by existing Google crawlers | n/a (no user agent of its own) |
| GPTBot | OpenAI | Training | GPTBot | Disallowing it signals content should not be used to train foundation models | yes (openai.com/gptbot.json) |
| OAI-SearchBot | OpenAI | Search (ChatGPT) | OAI-SearchBot | opted-out sites are not shown in ChatGPT search answers | yes (openai.com/searchbot.json) |
| ChatGPT-User | OpenAI | User-triggered fetch | ChatGPT-User | robots.txt rules may not apply, says OpenAI (user-initiated) | yes (openai.com/chatgpt-user.json) |
| ClaudeBot | Anthropic | Training | ClaudeBot | yes, Anthropic says its bots honor robots.txt | yes (claude.com/crawling/bots.json) |
| Claude-SearchBot | Anthropic | Search (Claude) | Claude-SearchBot | yes, Anthropic says its bots honor robots.txt | yes (claude.com/crawling/bots.json) |
| PerplexityBot | Perplexity | Search (Perplexity), not used for model training | PerplexityBot | controllable via robots.txt; the docs contain no explicit compliance statement | yes (perplexity.com/perplexitybot.json) |
| Applebot-Extended | Apple | Controls AI training (does not crawl, says Apple) | Applebot-Extended | robots.txt token only, applies to content Applebot already crawled | n/a (no crawler of its own) |
| CCBot | Common Crawl | Open web crawl archive | CCBot | can be blocked via robots.txt, says Common Crawl | yes (index.commoncrawl.org/ccbot.json) |
| Meta-ExternalAgent | Meta | Training foundation AI models, improving products | meta-externalagent | can be blocked via robots.txt, says Meta | not stated by the operator |

Sources: [OpenAI: Overview of OpenAI Crawlers](https://developers.openai.com/api/docs/bots); [Anthropic: Does Anthropic crawl data from the web, and how can site owners block the crawler? (updated 2026-04-07)](https://support.claude.com/en/articles/8896518-does-anthropic-crawl-data-from-the-web-and-how-can-site-owners-block-the-crawler); [Perplexity: Perplexity Crawlers](https://docs.perplexity.ai/guides/bots); [Google: Google's common crawlers (last updated 2026-07-14)](https://developers.google.com/crawling/docs/crawlers-fetchers/google-common-crawlers); [Google: Overview of Google crawlers and fetchers (last updated 2026-06-12)](https://developers.google.com/crawling/docs/crawlers-fetchers/overview-google-crawlers); [Google: Verifying Google crawlers and fetchers (IP range files)](https://developers.google.com/crawling/docs/crawlers-fetchers/verify-google-requests); [Apple: About Applebot (2026-09-04)](https://support.apple.com/en-us/119829); [Meta: Meta Web Crawlers](https://developers.facebook.com/docs/sharing/webmasters/web-crawlers/); [Common Crawl: CCBot](https://commoncrawl.org/ccbot). Last checked: October 8, 2026

## Related terms

- [Meta-ExternalAgent](https://seo-geo-glossary.com/en/glossary/meta-externalagent/index.md)
- [Meta-WebIndexer](https://seo-geo-glossary.com/en/glossary/meta-webindexer/index.md)
- [User-triggered fetcher](https://seo-geo-glossary.com/en/glossary/user-triggered-fetcher/index.md)
- [robots.txt](https://seo-geo-glossary.com/en/glossary/robots-txt/index.md)

## Sources

- [Meta Web Crawlers – Meta for Developers (Meta-ExternalFetcher section, checked 2026-10-07)](https://developers.facebook.com/docs/sharing/webmasters/web-crawlers/)

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Last updated: October 8, 2026
URL: https://seo-geo-glossary.com/en/glossary/meta-externalfetcher/