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

# Send a message



## OpenAPI

````yaml /api/openapi.yaml post /boards/{boardId}/messages
openapi: 3.1.0
info:
  title: SigmaChat API
  version: '1'
  description: |
    The REST surface for SigmaChat apps and bots. Authenticate every
    request with a bot token in the Authorization header. Every response
    carries X-RateLimit-Limit, X-RateLimit-Remaining, and
    X-RateLimit-Reset; errors use a stable envelope
    `{ "error": { "code": "..." } }`.
servers:
  - url: https://sigmachat.org/api/v1
security:
  - botToken: []
paths:
  /boards/{boardId}/messages:
    post:
      summary: Send a message
      parameters:
        - $ref: '#/components/parameters/boardId'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                content:
                  type: string
                  maxLength: 4000
                embeds:
                  type: array
                  maxItems: 4
                  items:
                    $ref: '#/components/schemas/Embed'
                replyTo:
                  type: string
                  format: uuid
      responses:
        '200':
          description: The stored message.
components:
  parameters:
    boardId:
      name: boardId
      in: path
      required: true
      schema:
        type: string
        format: uuid
  schemas:
    Embed:
      type: object
      description: Discord-shaped embed; needs a title, description, image, or fields.
      properties:
        title:
          type: string
          maxLength: 256
        description:
          type: string
          maxLength: 2048
        url:
          type: string
        color:
          type: string
          pattern: ^#[0-9a-f]{6}$
        image:
          type: object
          properties:
            url:
              type: string
        fields:
          type: array
          maxItems: 10
          items:
            type: object
            properties:
              name:
                type: string
                maxLength: 100
              value:
                type: string
                maxLength: 512
              inline:
                type: boolean
  securitySchemes:
    botToken:
      type: http
      scheme: bearer
      description: An app token from the in-app developer settings.

````