# Meta-WebIndexer

> Per Meta's crawler documentation, Meta-WebIndexer navigates the web to improve the quality of Meta AI's search results. It is a third Meta token alongside Meta-ExternalAgent and Meta-ExternalFetcher, and the newest of them.

| field | value |
|---|---|
| operator | Meta |
| category | AI search crawlers |
| robots.txt token | `Meta-WebIndexer` |
| user-agent contains | `Meta-WebIndexer` |
| robots.txt | operator publishes no robots.txt statement |
| verify by | no published verification method |
| published IP ranges | none published |
| prefixes mirrored | 0 IPv4 / 0 IPv6 |
| operator docs | https://developers.facebook.com/docs/sharing/webmasters/web-crawlers/ |
| last reviewed | 2026-09-14 |

## What blocking it costs you

You leave the index Meta AI answers from across Facebook, Instagram and WhatsApp — the largest assistant install base there is. A robots.txt that names the two older Meta tokens does not cover this one.

## Full user-agent string

```
Meta-WebIndexer
```

## Block it

```
User-agent: Meta-WebIndexer
Disallow: /
```

## Allow it

```
User-agent: Meta-WebIndexer
Allow: /
```

## Ask this page a question, with one GET

A question about this page, answered by a call you can make right now — no key, no account, no JSON-RPC, nothing to assemble. The query string is already filled in with this page's own subject.

- **How do I prove a request really is Meta-WebIndexer?**  
  `curl -s 'https://www.pathwren.workers.dev/tools/verification-methods?crawler=meta-webindexer&s=client-dossiers'`  
  The verification method its operator actually publishes — published IP ranges, reverse DNS, or nothing at all — and the mirror of it on this host.

Every parameter above is a value the endpoint reads, not an address it visits: nothing is fetched on your behalf. Called without any parameter, each endpoint returns its own specification instead of an error.

JSON: https://www.pathwren.workers.dev/crawler/meta-webindexer.json · index: https://www.pathwren.workers.dev/llms.txt