openapi: 3.1.0
info:
  title: Reference Chat Conversations Messages API
  description: Reference OpenAPI definition describing the typical shape of a chat platform API. Captures the vocabulary used for conversations, messages, and participants and serves as a profiling baseline for cataloguing concrete chat platform APIs.
  version: '1.0'
  contact:
    name: API Evangelist
    url: https://apievangelist.com/
servers:
- url: https://api.example.com/v1/chat
  description: Reference Production
security:
- bearerAuth: []
tags:
- name: Messages
paths:
  /conversations/{conversationId}/messages:
    get:
      operationId: listMessages
      summary: List messages in a conversation
      tags:
      - Messages
      parameters:
      - $ref: '#/components/parameters/conversationId'
      - name: cursor
        in: query
        schema:
          type: string
      - name: limit
        in: query
        schema:
          type: integer
          default: 50
      responses:
        '200':
          description: Messages page
          content:
            application/json:
              schema:
                type: object
                properties:
                  messages:
                    type: array
                    items:
                      $ref: '#/components/schemas/Message'
                  nextCursor:
                    type: string
    post:
      operationId: sendMessage
      summary: Send a message
      tags:
      - Messages
      parameters:
      - $ref: '#/components/parameters/conversationId'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - content
              properties:
                content:
                  type: string
                contentType:
                  type: string
                  enum:
                  - text
                  - markdown
                  - html
                metadata:
                  type: object
      responses:
        '201':
          description: Message sent
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Message'
components:
  parameters:
    conversationId:
      name: conversationId
      in: path
      required: true
      schema:
        type: string
  schemas:
    Message:
      type: object
      required:
      - id
      - content
      properties:
        id:
          type: string
        conversationId:
          type: string
        senderId:
          type: string
        content:
          type: string
        contentType:
          type: string
          enum:
          - text
          - markdown
          - html
        sentAt:
          type: string
          format: date-time
        editedAt:
          type: string
          format: date-time
        metadata:
          type: object
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT