---
title: "Send a message to a session"
method: POST
path: "/api/messaging/sessions/{sessionId}/messages"
tags: ["messaging"]
---

# Send a message to a session

`POST /api/messaging/sessions/{sessionId}/messages`

Send a message within an active session. The agent will process and respond to the message.

## Path parameters

- `sessionId` string, required

## Request body

- object
  - `content` string, required — The message content
  - `attachments` object[]
    - `type` string — Type of attachment
    - `url` string — URL of the attachment
    - `name` string — Name of the attachment
  - `metadata` object — Additional message metadata

## Response `201`

Message sent and processed successfully

- object
  - `id` string — Message ID
  - `content` string — The message content
  - `authorId` string, uuid
  - `createdAt` string, date-time
  - `metadata` object
  - `sessionStatus` object — Current session status after sending the message
    - `expiresAt` string, date-time — Updated expiration timestamp
    - `renewalCount` integer — Total number of times the session has been renewed
    - `wasRenewed` boolean — Whether the session was renewed by this message
    - `isNearExpiration` boolean — Whether the session is within the warning threshold

## Other responses

- `400` — Invalid request parameters
- `404` — Session not found
- `410` — Session has expired
- `500` — Internal server error

---

[API](https://skmtc.net/elizaos/apis/eliza-os-api.md) · [All operations](https://skmtc.net/elizaos/apis/eliza-os-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/elizaos/eliza-os-api/revisions/f43280bfdb0c/schema)