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User-Agent

A string sent with every HTTP request that identifies the browser or client making the request.

The User-Agent is an HTTP header that every browser and HTTP client sends with each request to identify itself. It typically includes the browser name, version, operating system, and rendering engine. For example, Chrome on Windows might send: "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 Chrome/120.0.0.0." Servers use this to serve appropriate content, and security tools use it to detect bots. Cloudflare's Browser Integrity Check (error 1010) blocks requests with suspicious or missing User-Agent headers.

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