From
RequestActiveThe From header contains the email address of the human user controlling the requesting agent. It is used by automated crawlers and bots to identify themselves and provide contact information. Search engine bots and well-behaved web crawlers send From so site operators can contact the bot owner if issues arise.
From: <email-address>
Description
From is intended for automated agents, not browsers. Well-behaved crawlers like Googlebot, Bingbot, and custom crawlers include From to let site administrators contact the bot operator. RFC 9110 recommends not sending From in browsers because it exposes user email addresses. When used in APIs, From can identify automated clients for rate-limiting and abuse contact purposes.
Examples
Crawler identification
http
GET /page HTTP/1.1
User-Agent: MyCrawler/1.0
From: [email protected]