---
title: "Send proactive message to a platform bot"
method: POST
path: "/api/v1/im/message"
tags: ["Open API"]
---

# Send proactive message to a platform bot

`POST /api/v1/im/message`

Send message directly to platform bot by umo + message chain payload.

## Request body

- SendMessageRequest
  - `umo` string, required — Unified message origin. Format: platform:message_type:session_id
  - `message` union, required
    - string
    - MessagePart[]
      - `type` 'plain' | 'reply' | 'image' | 'record' | 'file' | 'video', required
      - `text` string
      - `message_id` union
        - string
        - integer
      - `selected_text` string
      - `attachment_id` string
      - `filename` string
      - `path` string

## Response `200`

OK

- ApiResponseEmpty
  - `status` string
  - `message` string, nullable
  - `data` object

## Other responses

- `401` — Unauthorized
- `403` — Forbidden

## Changes

- **2026-03-09** `3d43cee2622a` — 1 info
  - endpoint added

[Change history](https://skmtc.dev/astrbotdevs/apis/astrbot-openapi-v1/changes/api/v1/im/message/post.md)

---

[API](https://skmtc.dev/astrbotdevs/apis/astrbot-openapi-v1.md) · [All operations](https://skmtc.dev/astrbotdevs/apis/astrbot-openapi-v1/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/astrbotdevs/astrbot-openapi-v1/revisions/3d43cee2622a/schema)