> ## Documentation Index > Fetch the complete documentation index at: https://docs.bango.com/llms.txt > Use this file to discover all available pages before exploring further. # Check available payment methods > Resource used to check available payment methods. ## OpenAPI ````yaml /openapi/legacy/payments/merchant-to-bango/openapi.yaml options /v5/transaction openapi: 3.0.0 info: title: Bango Payment API v5 description: > Changelog * 5.0.0: Initial release * 5.0.1: Add the CLIENT_ACTION_REQUIRED response code to the Transaction resource's POST method. Similar to the Identity resource's POST method, this lets the Bango Platform support payment routes that require user interactions. Currently, the only action that may be returned by the API is REDIRECT. Other actions may be added later. version: 5.0.1 servers: - description: SwaggerHub API Auto Mocking url: https://virtserver.swaggerhub.com/BangoProducts/Bango-Payment-API-v5/5.0.1 security: - basic: [] paths: /v5/transaction: options: tags: - Transaction summary: Check available payment methods description: Resource used to check available payment methods. operationId: Options requestBody: content: application/json: schema: $ref: '#/components/schemas/TransactionRequest' required: true responses: '200': description: >- Payment methods successfully identified | Testing - Prefer: status=200 content: application/json: schema: $ref: '#/components/schemas/PaymentMethodResponse' '202': description: Request accepted content: application/json: schema: $ref: '#/components/schemas/PaymentMethodResponse' examples: NOT_AVAILABLE: value: responseCode: NOT_AVAILABLE responseMessage: No valid payment methods were found. description: >- Testing - Prefer: status=202, preference-extension: responseCode=NOT_AVAILABLE PRICE_NOT_SUPPORTED: value: responseCode: PRICE_NOT_SUPPORTED responseMessage: Price not supported on suggested payment methods. description: >- Testing - Prefer: status=202, preference-extension: responseCode=PRICE_NOT_SUPPORTED USER_EXCEEDED_LIMIT: value: responseCode: USER_EXCEEDED_LIMIT responseMessage: User exceeded limit on suggested payment methods. description: >- Testing - Prefer: status=202, preference-extension: responseCode=USER_EXCEEDED_LIMIT '400': description: Bad request content: application/json: schema: $ref: '#/components/schemas/Response' examples: BAD_REQUEST: value: responseCode: BAD_REQUEST responseMessage: Invalid request. description: >- Testing - Prefer: status=400, preference-extension: responseCode=BAD_REQUEST INVALID_BANGOUSERID: value: responseCode: INVALID_BANGOUSERID responseMessage: Invalid bangoUserId. description: >- Testing - Prefer: status=400, preference-extension: responseCode=INVALID_BANGOUSERID '401': description: Unauthorized content: application/json: schema: $ref: '#/components/schemas/Response' examples: UNAUTHORIZED: value: responseCode: UNAUTHORIZED responseMessage: Invalid access credentials. description: 'Testing - Prefer: status=401' '500': description: Unexpected error content: application/json: schema: $ref: '#/components/schemas/Response' examples: INTERNAL_ERROR: value: responseCode: INTERNAL_ERROR responseMessage: The server encountered an unexpected condition. description: 'Testing - Prefer: status=500' '503': description: Service unavailable content: application/json: schema: $ref: '#/components/schemas/Response' example: SERVICE_UNAVAILABLE: value: responseCode: SERVICE_UNAVAILABLE responseMessage: The server is undergoing maintenance. description: 'Testing - Prefer: status=503' components: schemas: TransactionRequest: required: - paymentItems - bangoUserId type: object properties: bangoUserId: type: string example: '987654321' description: >- The Bango User ID of the user purchasing the item. Required to allow for per-user payment methods, and to check whether the user is permitted to purchase the item. paymentMethods: type: array items: type: string example: OPERATORBILLING description: >- Payment method type strings. If specified, defines the subset of supported payment methods you would like the Bango Platform to consider including in the response. If omitted, or if empty, the Bango Platform considers all supported payment methods. The currently supported payment method type strings are OPERATORBILLING and INTERNET. externalTransactionId: type: string example: my-tx-id-12345 description: >- Your own unique, persistent transaction ID, if you have one. This helps reconciliation processes. Required to use the Bango Platform idempotency feature. paymentItems: $ref: '#/components/schemas/PaymentItem' extensionData: $ref: '#/components/schemas/ExtensionData' PaymentMethodResponse: required: - responseCode - responseMessage type: object allOf: - $ref: '#/components/schemas/Response' - type: object properties: availablePaymentMethods: description: >- An array of objects, where each object has a number of properties. - type is a valid payment method type string, for example OPERATORBILLING - key is an identifier for the payment provider - description is a string you can show in the store's user interface to describe the payment method - parameters is an object of parameters applicable to the payment provider The same value of type may appear more than once in the array, in this case, the value of key distinguishes the different methods. If paymentMethods was included in the request, then type is always one of the strings specified in that array. type: array items: type: object properties: type: type: string example: OPERATORBILLING key: type: string example: SOME_NETWORK_NAME description: type: string example: Direct operator billing parameters: type: object Response: required: - responseCode - responseMessage type: object properties: responseCode: type: string example: OK responseMessage: type: string example: Success. PaymentItem: description: >- The item to be purchased. See Bango Payment API / API reference / Transaction Payment Items structure for information about this structure. Required to check whether the user is permitted to purchase the item, and to to check whether the prices are supported price points for the payment provider. type: array items: type: object properties: itemName: type: string example: My item itemDescription: type: string example: My item description itemCategory: type: string example: '1' externalPaymentItemId: type: string example: abcd-1234 submerchantReferenceKey: type: string example: submerchant1 priceList: $ref: '#/components/schemas/PriceList' ExtensionData: description: Additional data related to the transaction. type: object properties: some: type: string example: 123-456-789 some1: type: string example: 123-456-789 PriceList: type: array items: $ref: '#/components/schemas/Price' Price: type: object properties: grossAmount: type: string example: '3.99' currencyIso3: type: string example: USD financialBreakdown: $ref: '#/components/schemas/FinancialBreakdown' FinancialBreakdown: type: object properties: taxAmount: type: string example: '0' securitySchemes: basic: type: http description: Basic authentication scheme: basic ````