Send messages via the API

JavaScriptPOST /v0/profiles/{profile_uuid}/threads/{thread_uuid}/messages
Authorization: Bearer &lt;access_token&gt;
Content-Type: application/json

{
  "message": "Thanks for reaching out - someone will call you within the hour.",
  "type": "sms",
  "is_draft": false
}

Requires staff scope. You send into an existing thread — resolve or create the thread first.

Field	Notes
`message`	Required. The text body.
`type`	Required. `sms`, `fb`, `note`, `internal`, or `summary`. `note` / `summary` / `internal` are internal-only and are not sent to the contact. `goog` (Google Business Messages) is rejected — that channel is discontinued.
`is_draft`	Send `false` to actually send the message. See the warning below.
`media`	Array of media names previously uploaded via `POST /v0/profiles/{profile_uuid}/threads/{thread_uuid}/media-upload`. Valid only for `sms` and `fb`.
`scheduled`	ISO-8601 timestamp with a timezone offset, in the future. Not allowed for `note` / `summary`.

⚠️ is_draft defaults to true. If you omit is_draft, the message is saved as an unsent draft and never delivered. Always send "is_draft": false when you mean to send.

Response

JSON{
  "uuid": "...",
  "thread": "...",
  "message": "...",
  "type": "sms",
  "direction": "egress",
  "state": "pending",
  "creation": "&lt;ISO-8601&gt;",
  "modification": "&lt;ISO-8601&gt;",
  "sender": { ... }
}

state will be:

pending — accepted and queued for delivery (this is the success case)
scheduled — will send at scheduled
draft — saved but not sent (you omitted is_draft: false)

Other notes

The contact must have consent and must not be blocked, or you get a 422.
There is no character limit enforced by the API. Long SMS bodies are split into multiple carrier segments and billed per segment.
Sending a message here also fires your new_message webhook.