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POST
Inboxes are currently in private beta and only available to a limited number of users. The response shape might change before GA.Get early access if you’re interested in testing this feature.Once you have access, upgrade your Resend SDK to use the new methods:
Replies from the inbox address. to is taken from the message you reply to: its author, or its Reply-To address if it has one. When the inbox sent that message, the reply goes to the message’s original to recipients. Add more recipients with cc and bcc. The total number of recipients can’t exceed 50, counted after reply_all adds everyone on the message. At least one of html or text is required. The reply is threaded for the recipient. In-Reply-To is set to the Message-ID of the message you reply to, and References to that message’s References followed by its Message-ID. These headers can’t be set or overridden.

Path Parameters

Body Parameters

string | string[]
CC recipient email address. For multiple addresses, send as an array of strings. Not copied from the message you reply to unless reply_all is true, which merges these addresses with the copied ones, without duplicates.
string | string[]
BCC recipient email address. For multiple addresses, send as an array of strings. Not copied from the message you reply to.
string
The HTML body.
string
The plain-text body.
string
The subject of the reply. When omitted, the thread subject is used, prefixed with Re: if it isn’t already. Max 2000 characters.
boolean
default:"false"
Reply to everyone on the original message, not only its author. The reply goes to the author, or its Reply-To address if it has one, and to the message’s to and cc recipients, excluding the inbox’s own address. bcc recipients are never copied.
array
Filename and content of attachments (max 25MB of content per message). A path is fetched when the email is sent and does not count toward that limit.See examples
object
Custom headers to add to the email. In-Reply-To, References, and Reply-To can’t be set and return 422.

Headers

string
Add an idempotency key to prevent duplicated emails.
  • Should be unique per API request
  • Idempotency keys expire after 24 hours
  • Have a maximum length of 256 characters
Learn more

Response Fields

string
The ID of the queued outbound email.