---
title: "Send a message to an AI assistant."
method: POST
path: "/ai_assistants/{assistant_id}/messages"
tags: ["AI Assistants"]
---

# Send a message to an AI assistant.

`POST /ai_assistants/{assistant_id}/messages`

## Request

- Base URL: `https://h2ogpte.genai.h2o.ai/api/v1`
- URL: `https://h2ogpte.genai.h2o.ai/api/v1/ai_assistants/{assistant_id}/messages`
- Auth: HTTP bearer
- TypeScript: <https://skmtc.dev/h2o/apis/h2ogpte-rest-api/docs/ai_assistants/:assistant_id/messages/post.ts> (a function with typed inputs; its response is checked against the schema)

## Path parameters

- `assistant_id` string, required

## Request body

- AiAssistantMessageRequest
  - `content` string, required

## Response `201`

Successful operation

- object
  - `id` string, uuid: The newly created message ID

## Other responses

- `401`: Unauthorized - Invalid or missing API key
- `default`: Unexpected error

## Changes

- **2026-11-06** `a82a117320f4`: 1 info
  - endpoint added

[Operation history](https://skmtc.dev/h2o/apis/h2ogpte-rest-api/changes/ai_assistants/:assistant_id/messages/post.md)

---

[API](https://skmtc.dev/h2o/apis/h2ogpte-rest-api.md) - [All operations](https://skmtc.dev/h2o/apis/h2ogpte-rest-api/llms.txt) - [OpenAPI document](https://skmtc.dev/h2o/apis/h2ogpte-rest-api/revisions/a82a117320f4?raw)