Meta-ExternalAgentMeta says Meta-ExternalAgent crawls for uses such as training foundation AI models or improving products by indexing content directly. The page says to block a crawler by adding a Disallow for it, and that a robots.txt change can take up to 24 hours because crawlers may cache the file. The robots.txt example on the page uses User-agent: meta-externalagent. Meta-ExternalFetcher is a different token and may bypass robots.txt. Meta-WebIndexer is a different token.
trainingdisallow_is_opt_out. The vendor says disallowing this token opts that use out.meta-externalagent/1.1 (+/documentation/sharing/webmasters/web-crawlers) Meta says the log string will be similar to this one or to meta-externalagent/1.1. On 2026-10-18 the page was text/markdown, and the parenthetical path has no host. The robots.txt example on that page uses User-agent: meta-externalagent.curl -s https://whosthatbot.com/v1/crawlers/meta-externalagent
tools/call with name check_robots is the same check at POST /mcp. The pasted file disallows Meta-ExternalAgent on /docs and allows *. The call does not fetch a host.
curl -s https://whosthatbot.com/mcp -H 'content-type: application/json' -H 'accept: application/json, text/event-stream' -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"check_robots","arguments":{"robots_txt":"User-agent: Meta-ExternalAgent\nDisallow: /\n\nUser-agent: *\nAllow: /\n","path":"/docs","ids":["meta-externalagent"]}}}'
That call returns fetched_target false. This row is disallow via group Meta-ExternalAgent, rule Disallow: /.