ua-tracer
by Paul Kinlan
trace ylYpElKO
what does a user agent actually fetch, follow & run?
Trace ylYpElKO
First seen: 2026-08-27 08:27:06.758 UTC
User-Agent: Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)
Bot verification: ✓ verified Googlebot IP checked against published bot CIDR ranges; IP in Googlebot published range.
What this user agent did
Directly-referenced assets:
✓ fetched CSS
✓ fetched JS
✗ fetched image
✗ fetched font (HTML)
Document-level link hints:
✓ fetched favicon
✓ fetched apple-touch-icon
✗ fetched web manifest
✗ fetched preload
✓ fetched prefetch
Second-level follows (proves it parsed the linking file):
✗ followed CSS background-image
✗ followed CSS @font-face
✗ followed manifest icon
✓ followed CSS @import
Frames (does it descend into iframes?):
✓ fetched iframe document
✗ descended into iframe (loaded inner image)
Reporting (a report-only CSP is violated by inline styles; reports can arrive via HTTP headers with no JS, or via in-page beacons):
✗ sent a CSP/Reporting report (any path)
✗ delivered via report-uri/Report-To header (no JS)
✗ delivered via in-page beacon (securitypolicyviolation / ReportingObserver)
Social embed (Open Graph / Twitter card images):
✗ fetched og:image
✗ fetched twitter:image
JavaScript execution:
✗ EXECUTED classic JS
✗ EXECUTED ES module
✗ posted client timing
Server-side request waterfall
Every request the server received for this trace, in receive order. +ms is the delta from the
homepage request.
| Received | Δ | Kind | Method | User-Agent |
|---|---|---|---|---|
| 2026-08-27 08:27:06.758 UTC | +0 ms | homepage | GET | Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html) |
request headers (9){
"accept": "*/*",
"accept-encoding": "gzip, deflate, br",
"connection": "keep-alive",
"from": "googlebot(at)googlebot.com",
"host": "uatracer.com",
"traceparent": "00-c8b5a6d58740b329eb24a4815174d489-1ad345eb5df2628a-01",
"tracestate": "",
"user-agent": "Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)",
"via": "HTTP/1.1 ams.vultr.prod.deno-cluster.net"
}
|
||||
| 2026-08-27 08:27:10.888 UTC | +4130 ms | CSS | GET | Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +http://www.google.com/bot.html) Chrome/151.0.7922.137 Safari/537.36 |
request headers (12){
"accept": "text/css,*/*;q=0.1",
"accept-encoding": "gzip, deflate, br",
"accept-language": "en-US",
"connection": "keep-alive",
"cookie": "ua-tracer-trace=ylYpElKO",
"from": "googlebot(at)googlebot.com",
"host": "uatracer.com",
"referer": "https://uatracer.com/",
"traceparent": "00-c5daf9b4cf559cb07bb867ec4f5c29bd-456c9951f2ec2914-01",
"tracestate": "",
"user-agent": "Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +http://www.google.com/bot.html) Chrome/151.0.7922.137 Safari/537.36",
"via": "HTTP/1.1 ams.vultr.prod.deno-cluster.net"
}
|
||||
| 2026-08-27 08:27:11.016 UTC | +4258 ms | prefetch | GET | Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +http://www.google.com/bot.html) Chrome/151.0.7922.137 Safari/537.36 |
request headers (15){
"accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7",
"accept-encoding": "gzip, deflate, br",
"accept-language": "en-US",
"connection": "keep-alive",
"cookie": "ua-tracer-trace=ylYpElKO",
"from": "googlebot(at)googlebot.com",
"host": "uatracer.com",
"referer": "https://uatracer.com/",
"sec-purpose": "prefetch",
"traceparent": "00-87f1c1f6e5a344de327c3018c3e8a5a1-b1e78868fea8ff17-01",
"tracestate": "",
"user-agent": "Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +http://www.google.com/bot.html) Chrome/151.0.7922.137 Safari/537.36",
"via": "HTTP/1.1 ams.vultr.prod.deno-cluster.net",
"x-deno-userspace-traceparent": "00-87f1c1f6e5a344de327c3018c3e8a5a1-3574c2941786a035-01",
"x-deno-userspace-tracestate": ""
}
|
||||
| 2026-08-27 08:27:11.192 UTC | +4434 ms | ES module | GET | Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +http://www.google.com/bot.html) Chrome/151.0.7922.137 Safari/537.36 |
request headers (13){
"accept": "*/*",
"accept-encoding": "gzip, deflate, br",
"accept-language": "en-US",
"connection": "keep-alive",
"cookie": "ua-tracer-trace=ylYpElKO",
"from": "googlebot(at)googlebot.com",
"host": "uatracer.com",
"origin": "https://uatracer.com",
"referer": "https://uatracer.com/",
"traceparent": "00-0fbf81cd0abc2e9f7accd761c2caddfc-078f1a9fffbfe0b6-01",
"tracestate": "",
"user-agent": "Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +http://www.google.com/bot.html) Chrome/151.0.7922.137 Safari/537.36",
"via": "HTTP/1.1 ams.vultr.prod.deno-cluster.net"
}
|
||||
| 2026-08-27 08:27:11.748 UTC | +4990 ms | iframe document | GET | Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +http://www.google.com/bot.html) Chrome/151.0.7922.137 Safari/537.36 |
request headers (13){
"accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7",
"accept-encoding": "gzip, deflate, br",
"accept-language": "en-US",
"connection": "keep-alive",
"cookie": "ua-tracer-trace=ylYpElKO",
"from": "googlebot(at)googlebot.com",
"host": "uatracer.com",
"referer": "https://uatracer.com/",
"traceparent": "00-a12be4b234c59f1edf520fa4a60321b1-3ad32d6a676a4973-01",
"tracestate": "",
"upgrade-insecure-requests": "1",
"user-agent": "Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +http://www.google.com/bot.html) Chrome/151.0.7922.137 Safari/537.36",
"via": "HTTP/1.1 ams.vultr.prod.deno-cluster.net"
}
|
||||
| 2026-08-27 08:27:13.739 UTC | +6981 ms | JS | GET | Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +http://www.google.com/bot.html) Chrome/151.0.7922.137 Safari/537.36 |
request headers (12){
"accept": "*/*",
"accept-encoding": "gzip, deflate, br",
"accept-language": "en-US",
"connection": "keep-alive",
"cookie": "ua-tracer-trace=ylYpElKO",
"from": "googlebot(at)googlebot.com",
"host": "uatracer.com",
"referer": "https://uatracer.com/",
"traceparent": "00-6df9c51328bcb565b03aa94756995bae-e24a35c36589d5ae-01",
"tracestate": "",
"user-agent": "Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +http://www.google.com/bot.html) Chrome/151.0.7922.137 Safari/537.36",
"via": "HTTP/1.1 ams.vultr.prod.deno-cluster.net"
}
|
||||
| 2026-08-27 08:27:14.196 UTC | +7438 ms | CSS @import (nested stylesheet) | GET | Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +http://www.google.com/bot.html) Chrome/151.0.7922.137 Safari/537.36 |
request headers (12){
"accept": "text/css,*/*;q=0.1",
"accept-encoding": "gzip, deflate, br",
"accept-language": "en-US",
"connection": "keep-alive",
"cookie": "ua-tracer-trace=ylYpElKO",
"from": "googlebot(at)googlebot.com",
"host": "uatracer.com",
"referer": "https://uatracer.com/r/ylYpElKO/EJJzUvGL/style.css",
"traceparent": "00-0e3aa98f02b3fdfb5bc01a2cd89410d9-57daca8994faec02-01",
"tracestate": "",
"user-agent": "Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +http://www.google.com/bot.html) Chrome/151.0.7922.137 Safari/537.36",
"via": "HTTP/1.1 ams.vultr.prod.deno-cluster.net"
}
|
||||
| 2026-08-27 08:27:16.412 UTC | +9654 ms | apple-touch-icon | GET | Googlebot-Image/1.0 |
request headers (11){
"accept": "*/*",
"accept-encoding": "gzip, deflate, br",
"connection": "keep-alive",
"from": "googlebot(at)googlebot.com",
"host": "uatracer.com",
"traceparent": "00-85f969c8c3f32eaf4d89f1699da7e1da-6d8b559b722c306d-01",
"tracestate": "",
"user-agent": "Googlebot-Image/1.0",
"via": "HTTP/1.1 ams.vultr.prod.deno-cluster.net",
"x-deno-userspace-traceparent": "00-85f969c8c3f32eaf4d89f1699da7e1da-3b2d23746edf439e-01",
"x-deno-userspace-tracestate": ""
}
|
||||
| 2026-08-27 08:27:16.712 UTC | +9954 ms | favicon | GET | Googlebot-Image/1.0 |
request headers (11){
"accept": "*/*",
"accept-encoding": "gzip, deflate, br",
"connection": "keep-alive",
"from": "googlebot(at)googlebot.com",
"host": "uatracer.com",
"traceparent": "00-cc587181ab965422d17fd77acb2fa562-68b110ac8747e8a3-01",
"tracestate": "",
"user-agent": "Googlebot-Image/1.0",
"via": "HTTP/1.1 ams.vultr.prod.deno-cluster.net",
"x-deno-userspace-traceparent": "00-cc587181ab965422d17fd77acb2fa562-7df4ec063709b574-01",
"x-deno-userspace-tracestate": ""
}
|
||||