Meta Bots & Crawlers

Meta (formerly Facebook) operates multiple crawlers to support its family of social platforms. The facebookexternalhit crawler is the primary bot that fetches content to generate link previews when URLs are shared on Facebook. FacebookBot handles various crawling tasks across the Meta ecosystem. Meta-ExternalAgent and Meta-ExternalFetcher (with lowercase variations) are generic user-agents used for external resource fetching. These crawlers are essential for creating rich link previews with titles, descriptions, and images when content is shared on Facebook, Instagram, and other Meta platforms. Blocking these crawlers will prevent proper link previews on Meta's platforms.