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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:
Sends the draft from the inbox address. The draft needs a to recipient and html or text. A draft that is not a reply also needs a subject. Otherwise, the request returns a 422. A reply draft without a subject uses the thread subject with a Re: prefix. The whole email can be at most 40 MB. A draft that was already sent returns a 409.

Path Parameters

Body Parameters

The request body is optional and takes only headers. Without headers, send no body.
object | null
Custom headers to add to the email. You cannot set In-Reply-To, References, or Reply-To.

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
  • A retry with the same key returns the first successful response, with the idempotent-replayed: true header
  • A failed request is not stored, so you can retry it with the same key
  • Reusing the key with a different body, or while the first request is still running, returns a 409
Learn more

Response Fields

string
The ID of the sent email. Use it with the emails endpoints.