Reply to a conversation

POST/api/v1/email/threads/{id}/reply

POST /email/threads/{id}/reply

curl -X POST 'https://www.unitpost.com/api/v1/email/threads/thr_123/reply' \
  -H 'Authorization: Bearer YOUR_API_KEY' \
  -H 'User-Agent: my-app/1.0' \
  -H 'Content-Type: application/json' \
  -d '{ }'

Response · 200

{
  "object": "email",
  "id": "id_123",
  "status": "queued",
  "thread_id": "thread_123"
}

Reply, reply all or forward one received message of the conversation (received_email_id), as the inbox does: your text and/or html go on top and the original is quoted under them; a reply carries In-Reply-To and References; a forward carries the attachments you list in forward_attachment_ids. The message joins the conversation and the conversation is marked read. For a reply, send to the message's reply_to addresses, else its from. It goes out now (no scheduled_at) through the same checks as any send. Pass an Idempotency-Key: a retry with it never sends twice. A copy of one of your own sends (sent_by_us) is never forwarded or quoted, since what you send isn't readable through the API: a reply to it goes without the quote, and a forward of it is a 403. Also requires emails:read (a reply quotes mail). Requires the emails:send capability.

Parameters2 fields

Field	Type	Description
`id`required	string · path	—
`Idempotency-Key`	string · header	Any unique string (1–256 characters, e.g. a UUID). Retrying with the same key and the same body within 24 hours returns the first result instead of sending again; the same key with a different body is `409 invalid_idempotent_request`, and one still in flight is `409 concurrent_idempotent_requests`.

Request body13 fields

Field	Type	Description
`received_email_id`required	string	The received message (`inb_…`) in this conversation to answer or forward.
`mode`required	enumreply \| reply_all \| forward	`reply` (the sender), `reply_all` (everyone on it), or `forward` (to someone new, with the original's attachments you pick).
`from`required	string	One of your sending addresses, e.g. the address the message came in on.
`to`required	string \| string[]	For a reply: the message's `reply_to`, else its `from`. Up to 50.
`cc`	string \| string[]	Copy recipients, up to 50.
`bcc`	string \| string[]	Blind-copy recipients, up to 50.
`subject`required	string	Usually `Re: <their subject>` (or `Fwd:`).
`text`	string	Your words, plain text. The original is quoted under them.
`html`	string	Your words, HTML. The original is quoted under them.
`include_quote`	boolean	Quote the original under a reply (default true; a forward always carries it). A copy of one of your own sends (`sent_by_us`) is never quoted: left out, it defaults to false there, and `true` is a `403`.
`forward_attachment_ids`	string[]	Forward only: the original's attachments to carry over (their `id`s).
`attachments`	object[]	Files to attach: `content` (base64) or `path` (an https URL), up to 20 with the carried-over ones.
`tracking`	boolean	Open and click tracking for this message; omitted = the sending domain's default.

Response · 200 fields4 fields

Field	Type	Description
`object`required	enumemail	—
`id`required	string	The sent email (`email_…`); read it with `GET /email/{id}`.
`status`required	enumqueued \| scheduled	—
`thread_id`required	string	—

200400401403404409422429

Reply to a conversation

Reply to a conversation

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