User Agent
A user agent is an HTTP header string identifying the client's browser, OS and device — trivially spoofed by bots, still useful when paired with TLS or JA4.
What is a User Agent?
A user agent is a string included in HTTP requests by browsers, bots, or other clients to identify themselves to web servers. It typically contains information about the client software, operating system, and device type. Web servers use user agent strings to deliver appropriate content, optimize compatibility, and analyze traffic. User agents play a key role in web development, analytics, and security.