User-Agent

meta-externalagent/1.1 (+https://developers.facebook.com/docs/sharing/webmasters/crawler)

first seen 2026-07-11 12:17 · last seen 2026-08-03 03:43 · JSON

Bot verification

This User-Agent declares a bot or user-triggered fetcher. Each connection's IP is checked at ingest against the verification channels the operator publishes — its crawler IP ranges and, where documented, forward-confirmed reverse DNS. A claim either channel confirms is identified; one confirmed by neither — outside the ranges, inside a different operator's, or failing the DNS check — is an impersonation signal. Meta publishes its network rather than crawler ranges, so its identified claims are network-confirmed and its unconfirmed misses are unverified claims, not proven spoofs. bot-claim anomalies →

claims	identified	unconfirmed miss	wrong operator	unconfirmed rate
Meta	0	3	0	100.0%

Decomposed attributes

Browser / client	`meta-externalagent 1.1`
Device class	`bot`
Declared URL	`https://developers.facebook.com/docs/sharing/webmasters/crawler`
Note	`inferred from the self-declared string — a claim, not a measurement; compare with the wire fingerprints above`

Co-observed signals

Signals from other families seen in the same observation. A fingerprint spread thinly across many lower-layer signatures is a classic inconsistency signal.

TLS ClientHello (JA4)

fingerprint	co-occurrences
`t13d1516h2_8daaf6152771_d8a2da3f94cd` Match?Exact match in Thumbprint's published controlled catalog captures: chromium 149.0.7827.102, chrome 149.0.7827.102, chrome 149.0.7827.156, +25 more.The fingerprint page shows the full measured match list. More on the catalog.	2
`t13d131300_f57a46bbacb6_1bd98dace775`	2
`t13d131200_f57a46bbacb6_9249cab70c77`	1

HTTP request (JA4H)

fingerprint	co-occurrences
`ge20nn020000_fb4f949fd323_000000000000_000000000000`	2
`po11nn060000_a35477c4bdb5_000000000000_000000000000`	1
`ge11nr040000_e1d2031bdfea_000000000000_000000000000`	1
`ge11nr05enus_f3bb7aa45ec4_000000000000_000000000000`	1

HTTP/2 frames (Akamai)

fingerprint	co-occurrences
`2:0;4:4194304;5:16384;6:10485760\|1073741824\|0\|a,m,p,s` Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.26.6, go-net/http 1.26.8, go-net/http 1.26.7, +6 more.The fingerprint page shows the full measured match list. More on the catalog.	2

TCP SYN (p0f)

fingerprint	co-occurrences
`4:58+6:0:1420:mss*30,9:mss,sok,ts,nop,ws:df,id+:0`	2
`4:58+6:0:1420:mss*46,10:mss,sok,ts,nop,ws:df,id+:0`	1
`4:51+13:0:1380:65535,13:mss,sok,ts,nop,ws:df,id+:0`	1
`6:46+18:0:1440:mss*30,9:mss,sok,ts,nop,ws:flow:0`	1

TCP SYN (JA4T)

fingerprint	co-occurrences
`42600_2-4-8-1-3_1420_9`	2
`65320_2-4-8-1-3_1420_10`	1
`65535_2-4-8-1-3_1380_13`	1
`43200_2-4-8-1-3_1440_9`	1

Country

fingerprint	co-occurrences
`US` · United States	2
`NL` · Netherlands	2
`DE` · Germany	1

Network (ASN)

fingerprint	co-occurrences
`AS396982` · Google LLC	3
`AS13335` · Cloudflare, Inc.	1
`AS206216` · Advin Services LLC	1