---
title: "Send Message"
method: POST
path: "/v0/inboxes/{inbox_id}/messages/send"
tags: ["InboxesMessages"]
---

# Send Message

`POST /v0/inboxes/{inbox_id}/messages/send`

**CLI:**
```bash
agentmail inboxes:messages send --inbox-id <inbox_id> --to recipient@example.com --subject "Hello" --text "Body"
```

## Path parameters

- `inbox_id` string, required — The ID of the inbox.

## Request body

- SendMessageRequest
  - `labels` string[] — Labels of message.
  - `reply_to` union
    - string
    - string[]
  - `to` union
    - string
    - string[]
  - `cc` union
    - string
    - string[]
  - `bcc` union
    - string
    - string[]
  - `subject` string — Subject of message.
  - `text` string — Plain text body of message.
  - `html` string — HTML body of message.
  - `attachments` SendAttachment[] — Attachments to include in message.
    - `filename` string — Filename of attachment.
    - `content_type` string — Content type of attachment.
    - `content_disposition` 'inline' | 'attachment' — Content disposition of attachment.
    - `content_id` string — Content ID of attachment.
    - `content` string, nullable — Base64 encoded content of attachment.
    - `url` string, nullable — URL to the attachment.
  - `headers` SendMessageHeaders — Headers to include in message.

## Response `200`

- SendMessageResponse
  - `message_id` string, required — ID of message.
  - `thread_id` string, required — ID of thread.

## Other responses

- `400`
- `403`
- `404`
- `409`

---

[API](https://skmtc.net/agentmail-to/apis/api.md) · [All operations](https://skmtc.net/agentmail-to/apis/api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/agentmail-to/api/revisions/394ddcdd9c29/schema)