openapi: 3.1.0
info:
  title: Western Union Mass Payments Balances Health API
  description: The Western Union Mass Payments API enables financial institutions and enterprise customers to send up to 10,000 international payments in a single batch across 130+ currencies in 200+ countries and territories. The API supports payment lifecycle management including batch creation, adding payments, FX quotes, committing, and tracking. Authentication requires mutual TLS (mTLS) client certificates provided by Western Union upon partnership enrollment.
  version: v1
  contact:
    name: Western Union Partnership Program
    url: https://developer.westernunion.com/getting-started.html
    email: wuconnect@westernunion.com
  license:
    name: Western Union Partner Terms
    url: https://developer.westernunion.com/getting-started.html
servers:
- url: https://api.westernunion.com
  description: Production endpoint
- url: https://api-sandbox.westernunion.com
  description: Sandbox for testing
tags:
- name: Health
  description: API health check.
paths:
  /Ping:
    get:
      operationId: ping
      summary: Health Check
      description: Verifies the API is available and the client's mTLS credentials are valid. Returns a simple pong response.
      tags:
      - Health
      security:
      - mtlsAuth: []
      responses:
        '200':
          description: API is healthy.
          content:
            application/json:
              schema:
                type: object
                properties:
                  status:
                    type: string
                    example: pong
        '401':
          description: Invalid or missing client certificate.
components:
  securitySchemes:
    mtlsAuth:
      type: mutualTLS
      description: Mutual TLS authentication using client certificates provided by Western Union upon enrollment in the Partnership Program. Include the certificate and key with every request.