cloudflare/references/email-workers/api.md

Email Workers APIs

Fetch the relevant page for current interfaces and return types.

Task	Documentation
Implement the handler; inspect envelope addresses, headers, raw content, or size	Email handler API
Forward, add forwarding headers, reject, or reply with MIME and threading	Email actions and reply requirements
Parse MIME bodies and attachments	Email handler parsing guidance — follow its postal-mime reference
Send new outbound mail or an existing raw MIME message	Sending Workers API
Configure sender and recipient restrictions	Send bindings
Set outbound headers	Email headers
Generate Worker and binding types	Workers TypeScript

Envelope addresses describe SMTP transport; message headers describe the message. Neither an address comparison nor a display header replaces email authentication.