openapi: 3.1.0
info:
  title: Fiserv BankingHub 3-D Secure Refund API
  description: The Fiserv BankingHub API provides RESTful access to core banking operations including account management, transactions, transfers, payments, and party (customer) management. BankingHub enables financial institutions and fintech partners to integrate account opening, fund transfers, payment processing, and customer data management into their applications.
  version: 1.0.0
  contact:
    name: Fiserv Developer Support
    url: https://developer.fiserv.com/product/BankingHub
  termsOfService: https://www.fiserv.com/en/legal.html
servers:
- url: https://cert.api.fiservapps.com
  description: Certification Environment
- url: https://prod.api.fiservapps.com
  description: Production Environment
security:
- bearerAuth: []
tags:
- name: Refund
  description: Refund previously captured and settled transactions.
paths:
  /refund:
    put:
      operationId: refundTransaction
      summary: Fiserv Refund a settled transaction
      description: Processes a refund for a previously captured and settled transaction. Supports full and partial refunds.
      tags:
      - Refund
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/RefundRequest'
      responses:
        '200':
          description: Refund processed
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/RefundResponse'
        '400':
          description: Bad request
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '401':
          description: Unauthorized
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
components:
  schemas:
    RefundRequest:
      type: object
      description: Refund request payload.
      required:
      - merchid
      - retref
      properties:
        merchid:
          type: string
          description: The CardPointe merchant ID.
        retref:
          type: string
          description: The retrieval reference number of the transaction to refund.
        amount:
          type: string
          description: The refund amount. If omitted, a full refund is processed.
    RefundResponse:
      type: object
      description: Refund response payload.
      properties:
        merchid:
          type: string
          description: The merchant identifier.
        retref:
          type: string
          description: The retrieval reference number.
        amount:
          type: string
          description: The refunded amount.
        respcode:
          type: string
          description: The response code.
        resptext:
          type: string
          description: The response text.
    ErrorResponse:
      type: object
      description: Error response payload.
      properties:
        respstat:
          type: string
          description: The response status (C for declined/error).
        respcode:
          type: string
          description: The error response code.
        resptext:
          type: string
          description: A human-readable error message.
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT
      description: OAuth 2.0 Bearer token for API authentication.
externalDocs:
  description: BankingHub API Documentation
  url: https://developer.fiserv.com/product/BankingHub/docs/?path=docs/get-started.md