whatsync-app Business templates (Attio workflows) API

openapi: 3.2.0
info:
  title: WhatSync Business templates (Attio workflows) API
  version: '2026-10-01'
  description: 'Use WhatsApp from Claude, ChatGPT, n8n, Make, Zapier or your own code: read, search and send WhatsApp messages, manage groups, Business templates, campaigns and forms, and receive signed webhooks. WhatsApp tools and signed webhooks with an account API key. API keys and webhooks are part of the Max plan and up (https://whatsync.app/pricing); other accounts get 403 plan_required. Personal WhatsApp numbers can send 50 messages a day through the API (429 daily_limit_reached); the official Business API has no WhatSync daily limit. Docs: https://whatsync.app/docs/api/quickstart The Business template routes under /api/send-template use a workspace service API key instead and are used by Attio workflows.'
  contact:
    name: WhatSync support
    email: hello@whatsync.app
    url: https://whatsync.app/contact
servers:
- url: https://whatsync.app
security:
- bearerKey: []
- headerKey: []
tags:
- name: Business templates (Attio workflows)
  description: List approved Meta WhatsApp templates and send one from an Attio workflow with a workspace service API key.
  externalDocs:
    url: https://whatsync.app/attio/whatsapp-business/how-to-send-a-whatsapp-message
paths:
  /api/send-template:
    get:
      operationId: listApprovedWhatsAppTemplates
      summary: List approved WhatsApp templates
      description: Returns approved Meta WhatsApp templates for the requested WhatSync connection.
      tags:
      - Business templates (Attio workflows)
      security:
      - ServiceApiKey: []
      - ServiceBearerAuth: []
      parameters:
      - $ref: '#/components/parameters/ConnectionId'
      responses:
        '200':
          description: Approved templates returned by Meta.
          content:
            application/json:
              schema:
                type: object
                additionalProperties: true
        '400':
          $ref: '#/components/responses/TemplateBadRequest'
        '401':
          $ref: '#/components/responses/TemplateUnauthorized'
        '403':
          $ref: '#/components/responses/TemplateForbidden'
        '500':
          $ref: '#/components/responses/TemplateServerError'
    post:
      operationId: sendApprovedWhatsAppTemplate
      summary: Send an approved WhatsApp template
      description: Sends a Meta-approved WhatsApp template using the official WhatsApp Business connection identified by connectionId.
      tags:
      - Business templates (Attio workflows)
      security:
      - ServiceApiKey: []
      - ServiceBearerAuth: []
      parameters:
      - $ref: '#/components/parameters/ConnectionId'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/SendTemplateRequest'
            examples:
              basic:
                summary: Send a template with body parameters
                value:
                  phoneNumber: '+14155550123'
                  templateName: appointment_reminder
                  language: en
                  parameters:
                    param_0: Aarav
                    param_1: Tuesday
      responses:
        '200':
          description: The template request was accepted by Meta.
          content:
            application/json:
              schema:
                type: object
                additionalProperties: true
        '400':
          $ref: '#/components/responses/TemplateBadRequest'
        '401':
          $ref: '#/components/responses/TemplateUnauthorized'
        '403':
          $ref: '#/components/responses/TemplateForbidden'
        '500':
          $ref: '#/components/responses/TemplateServerError'
components:
  responses:
    TemplateForbidden:
      description: The authenticated actor may not use this connection.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/TemplateError'
    TemplateServerError:
      description: The request failed inside WhatSync or a required upstream service.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/TemplateError'
    TemplateUnauthorized:
      description: No valid session or service API key was supplied.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/TemplateError'
    TemplateBadRequest:
      description: The query or JSON body is invalid.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/TemplateError'
  schemas:
    SendTemplateRequest:
      type: object
      additionalProperties: false
      required:
      - phoneNumber
      - templateName
      properties:
        phoneNumber:
          type: string
          minLength: 1
          description: Destination phone number, preferably in E.164 format.
        templateName:
          type: string
          minLength: 1
          description: Name of a Meta-approved template.
        parameters:
          type: object
          additionalProperties:
            type: string
          description: Template body values. param_0, param_1, and so on preserve order.
        language:
          type: string
          default: en
          description: Approved template language code.
        header:
          $ref: '#/components/schemas/TemplateHeader'
    TemplateHeader:
      type: object
      additionalProperties: false
      required:
      - type
      properties:
        type:
          type: string
          enum:
          - text
          - image
          - video
          - document
        text:
          type: string
          minLength: 1
        link:
          type: string
          format: uri
        id:
          type: string
          minLength: 1
        filename:
          type: string
          minLength: 1
      description: Template header. Text headers require text. Media headers require either link or id. A linked document also requires filename.
    TemplateError:
      type: object
      required:
      - error
      properties:
        success:
          type: boolean
        error:
          type: string
        code:
          type: string
        details:
          type: array
          items:
            type: object
            additionalProperties: true
      additionalProperties: true
  parameters:
    ConnectionId:
      name: connectionId
      in: query
      required: true
      description: WhatSync connection ID for the official WhatsApp Business connection.
      schema:
        type: string
        minLength: 1
  securitySchemes:
    bearerKey:
      type: http
      scheme: bearer
      bearerFormat: wsk_live_
    headerKey:
      type: apiKey
      in: header
      name: X-API-Key
    ServiceApiKey:
      type: apiKey
      in: header
      name: x-service-api-key
      description: Workspace service API key shown in WhatSync. Only for /api/send-template.
    ServiceBearerAuth:
      type: http
      scheme: bearer
      bearerFormat: WhatSync service API key
      description: The workspace service API key as a Bearer token. Only for /api/send-template.