Meta-ExternalAgent is Meta's web crawler designed to collect training data for their various AI initiatives, including large language models and other machine learning systems. This bot represents Meta's efforts to gather diverse, high-quality web content to improve their AI capabilities across products like Facebook, Instagram, and WhatsApp. The crawler operates with respect for web standards and robots.txt directives, allowing website owners to control whether their content is used in Meta's AI training datasets. As Meta continues to invest heavily in AI research and development, this bot plays a crucial role in ensuring their models have access to comprehensive training data.
⚠️ AI Training Notice
This bot may collect and use your website content for AI model training. Consider whether you want your content used for this purpose before allowing access.
Detection Patterns
Multiple ways to detect Meta-ExternalAgent in your application:
// PHP Detection for Meta-ExternalAgent
function detect_meta_externalagent() {
$user_agent = $_SERVER['HTTP_USER_AGENT'] ?? '';
$pattern = '/Meta\\-ExternalAgent/i';
if (preg_match($pattern, $user_agent)) {
// Log the detection
error_log('Meta-ExternalAgent detected from IP: ' . $_SERVER['REMOTE_ADDR']);
// Set cache headers
header('Cache-Control: public, max-age=3600');
header('X-Robots-Tag: noarchive');
// Optional: Serve cached version
if (file_exists('cache/' . md5($_SERVER['REQUEST_URI']) . '.html')) {
readfile('cache/' . md5($_SERVER['REQUEST_URI']) . '.html');
exit;
}
return true;
}
return false;
}
# Python/Flask Detection for Meta-ExternalAgent
import re
from flask import request, make_responsedef detect_meta_externalagent():
user_agent = request.headers.get('User-Agent', '')
pattern = r'Meta-ExternalAgent'
if re.search(pattern, user_agent, re.IGNORECASE):
# Create response with caching
response = make_response()
response.headers['Cache-Control'] = 'public, max-age=3600'
response.headers['X-Robots-Tag'] = 'noarchive'
return True
return False# Django Middleware
class MetaExternalAgentMiddleware:
def __init__(self, get_response):
self.get_response = get_response
def __call__(self, request):
if self.detect_bot(request):
# Handle bot traffic
pass
return self.get_response(request)
// JavaScript/Node.js Detection for Meta-ExternalAgent
const express = require('express');
const app = express();// Middleware to detect Meta-ExternalAgent
function detectMetaExternalAgent(req, res, next) {
const userAgent = req.headers['user-agent'] || '';
const pattern = /Meta-ExternalAgent/i;
if (pattern.test(userAgent)) {
// Log bot detection
console.log('Meta-ExternalAgent detected from IP:', req.ip);
// Set cache headers
res.set({
'Cache-Control': 'public, max-age=3600',
'X-Robots-Tag': 'noarchive'
});
// Mark request as bot
req.isBot = true;
req.botName = 'Meta-ExternalAgent';
}
next();
}app.use(detectMetaExternalAgent);
# Apache .htaccess rules for Meta-ExternalAgent# Block completely
RewriteEngine On
RewriteCond %{HTTP_USER_AGENT} Meta\-ExternalAgent [NC]
RewriteRule .* - [F,L]# Or redirect to a static version
RewriteCond %{HTTP_USER_AGENT} Meta\-ExternalAgent [NC]
RewriteCond %{REQUEST_URI} !^/static/
RewriteRule ^(.*)$ /static/$1 [L]# Or set environment variable for PHP
SetEnvIfNoCase User-Agent "Meta\-ExternalAgent" is_bot=1# Add cache headers for this bot
<If "%{HTTP_USER_AGENT} =~ /Meta\-ExternalAgent/i">
Header set Cache-Control "public, max-age=3600"
Header set X-Robots-Tag "noarchive"
</If>
# Nginx configuration for Meta-ExternalAgent# Map user agent to variable
map $http_user_agent $is_meta_externalagent {
default 0;
~*Meta\-ExternalAgent 1;
}server {
# Block the bot completely
if ($is_meta_externalagent) {
return 403;
}
# Or serve cached content
location / {
if ($is_meta_externalagent) {
root /var/www/cached;
try_files $uri $uri.html $uri/index.html @backend;
}
try_files $uri @backend;
}
# Add headers for bot requests
location @backend {
if ($is_meta_externalagent) {
add_header Cache-Control "public, max-age=3600";
add_header X-Robots-Tag "noarchive";
}
proxy_pass http://backend;
}
}
Should You Block This Bot?
Recommendations based on your website type:
Site Type
Recommendation
Reasoning
E-commerce
Limit Access
Protect pricing and inventory data from AI training
Blog/News
Consider Blocking
Your content may be used for AI training without compensation
SaaS Application
Block
No benefit for application interfaces; preserve resources
Documentation
Selective
Allow for public docs, block for internal docs
Corporate Site
Limit
Allow for public pages, block sensitive areas like intranets