MailSlurp guide agent setup

Title: BCC and CC in SMTP Emails: API Fields, Headers, and Tests
Description: Understand CC and BCC in SMTP email, how recipient fields behave in APIs, and how to test BCC visibility with MailSlurp inboxes.
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Markdown URL: https://www.mailslurp.com/guides/bcc-and-cc-in-smtp-emails.md

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