SleekFlow

SleekFlow Messaging API

Send messages, files, and internal notes; check conversation windows.

GitHub OpenAPI

Operations 4

POST /v1/messages Send message #
POST /v1/messages/file Send local file with message #
POST /v1/messages/note Send internal note #
GET /v1/messages/conversation-window Check WhatsApp Business conversation window #

Documentation

📖
Documentation
https://help.sleekflow.io/en_US/integrations/platform-api-integration
📖
APIReference
https://apidoc.sleekflow.io/docs/platform-api/3z6iu3fo5evix-contacts
📖
APIReference
https://apidoc.sleekflow.io/docs/platform-api/9ty13q0r571om-messaging
📖
APIReference
https://apidoc.sleekflow.io/docs/platform-api/nijbjgxrs4s50-sleek-flow-platform-api
📖
APIReference
https://apidoc.sleekflow.io/docs/platform-api/t21aeu2xvtiw6-staff-and-team

Specifications

⚙
OpenAPI
https://raw.githubusercontent.com/api-evangelist/sleekflow/refs/heads/main/openapi/sleekflow-messaging-api-openapi.yml

Other Resources

🔗
PostmanCollection
https://raw.githubusercontent.com/api-evangelist/sleekflow/refs/heads/main/collections/sleekflow.postman_collection.json
🔗
Review
https://raw.githubusercontent.com/api-evangelist/sleekflow/refs/heads/main/review.yml

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OpenAPI Specification

sleekflow-messaging-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  title: SleekFlow Platform Messaging API
  description: The SleekFlow Platform API lets you build custom integrations on top of the SleekFlow omnichannel messaging platform.
  termsOfService: https://sleekflow.io/terms-of-service
  contact:
    name: SleekFlow Support
    url: https://help.sleekflow.io
  version: '1.0'
servers:
- url: https://api.sleekflow.io
  description: SleekFlow Platform API
security:
- ApiKeyAuth: []
tags:
- name: Messaging
  description: Send messages, files, and internal notes; check conversation windows.
paths:
  /v1/messages:
    post:
      operationId: sendMessage
      tags:
      - Messaging
      summary: Send message
      description: Sends a message to a contact over a supported channel such as WhatsApp, Facebook Messenger, Instagram, WeChat, LINE, or SMS.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/SendMessageRequest'
      responses:
        '200':
          description: The sent message.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Message'
  /v1/messages/file:
    post:
      operationId: sendFileMessage
      tags:
      - Messaging
      summary: Send local file with message
      description: Sends a message with an attached local file to a contact.
      requestBody:
        required: true
        content:
          multipart/form-data:
            schema:
              type: object
              properties:
                channel:
                  type: string
                contactId:
                  type: string
                message:
                  type: string
                file:
                  type: string
                  format: binary
              required:
              - channel
              - contactId
              - file
      responses:
        '200':
          description: The sent message.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Message'
  /v1/messages/note:
    post:
      operationId: sendInternalNote
      tags:
      - Messaging
      summary: Send internal note
      description: Adds an internal note to a conversation, visible only to staff.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                conversationId:
                  type: string
                message:
                  type: string
              required:
              - conversationId
              - message
      responses:
        '200':
          description: The created note.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Message'
  /v1/messages/conversation-window:
    get:
      operationId: checkConversationWindow
      tags:
      - Messaging
      summary: Check WhatsApp Business conversation window
      description: Checks whether the 24-hour WhatsApp Business customer service window is open for a contact, determining whether a free-form message or a template message must be sent.
      parameters:
      - name: contactId
        in: query
        required: true
        schema:
          type: string
      responses:
        '200':
          description: Conversation window status.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ConversationWindow'
components:
  schemas:
    ConversationWindow:
      type: object
      properties:
        contactId:
          type: string
        isWithinWindow:
          type: boolean
        windowExpiresAt:
          type: string
          format: date-time
    SendMessageRequest:
      type: object
      properties:
        contactId:
          type: string
        channel:
          type: string
          description: Channel code such as whatsapp, whatsappcloudapi, facebook, instagram, wechat, line, or sms.
        message:
          type: string
        messageType:
          type: string
      required:
      - contactId
      - channel
      - message
    Message:
      type: object
      properties:
        id:
          type: string
        conversationId:
          type: string
        contactId:
          type: string
        channel:
          type: string
        direction:
          type: string
          enum:
          - inbound
          - outbound
        messageType:
          type: string
        message:
          type: string
        createdAt:
          type: string
          format: date-time
  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      in: header
      name: X-Sleekflow-ApiKey
      description: Platform API key issued from the SleekFlow Integrations dashboard (Admin access required).