> ## Documentation Index
> Fetch the complete documentation index at: https://docs.litellm-agent-platform.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Send a prompt



## OpenAPI

````yaml POST /session/{session_id}/prompt_async
openapi: 3.0.3
info:
  title: LiteLLM Agent Platform API
  description: >-
    Unified API for the LiteLLM Agent Platform — gateway, agents, sessions, and
    runtimes.
  version: 0.1.0
servers:
  - url: https://litellm-rust.onrender.com
    description: Production
  - url: http://localhost:4000
    description: Local (Docker Compose)
security:
  - BearerAuth: []
tags:
  - name: System
  - name: Models
  - name: Messages
  - name: API Keys
  - name: Agents
  - name: Sessions
  - name: Runtimes
  - name: MCP
paths:
  /session/{session_id}/prompt_async:
    post:
      tags:
        - Sessions
      summary: Queue a prompt for a session
      operationId: sendSessionPrompt
      parameters:
        - name: session_id
          in: path
          required: true
          schema:
            type: string
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/PromptRequest'
      responses:
        '204':
          description: Prompt queued
        '401':
          description: Unauthorized
        '404':
          description: Session not found
      security:
        - BearerAuth: []
components:
  schemas:
    PromptRequest:
      type: object
      required:
        - model
        - parts
      properties:
        model:
          type: object
          required:
            - modelID
          properties:
            modelID:
              type: string
              example: claude-opus-4-5
        parts:
          type: array
          items:
            type: object
            required:
              - type
              - text
            properties:
              type:
                type: string
                enum:
                  - text
                example: text
              text:
                type: string
                example: Summarize the repo README.
  securitySchemes:
    BearerAuth:
      type: http
      scheme: bearer
      description: 'Your LITELLM_MASTER_KEY. Default for local Docker Compose: `sk-local`'

````