# API Reference
source: https://developer.mastercard.com/account-to-account-commerce-for-dsp/documentation/api-reference/index.md

The following table summarizes Account to Account Commerce APIs that facilitate different operations for the debtor service provider.

|                                                                                                                                                      |                                         |                 |                                                                                                                                                                             |
|------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------|-----------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| **[DSP to Mastercard](https://developer.mastercard.com/account-to-account-commerce-for-dsp/documentation/api-reference/dsp-to-mastercard/index.md)** |                                         |                 |                                                                                                                                                                             |
| **Feature**                                                                                                                                          | **APIs**                                | **HTTP Method** | **Description**                                                                                                                                                             |
| **Payment Requests**                                                                                                                                 | **Payment Request Retrievals**          | POST            | Enables the debtor service provider to obtain the payment request details from Mastercard                                                                                   |
| **Payment Requests**                                                                                                                                 | **Payment Confirmation Advices**        | POST            | Enables the debtor service provider to provide confirmation for a payment.                                                                                                  |
| **Payment Requests**                                                                                                                                 | **Payment Step up Advices**             | POST            | Enables the debtor service provider to request step up for a payment.                                                                                                       |
| **Agreements**                                                                                                                                       | **Agreement retrieval**                 | POST            | Enables the debtor service providers to retrieve agreement details.                                                                                                         |
| **Agreements**                                                                                                                                       | **Agreement retrieval lists**           | POST            | Enables the debtor service providers to retrieve agreement details.                                                                                                         |
| **Agreements**                                                                                                                                       | **Agreement update notification**       | POST            | Enables the debtor service providers to notify Mastercard for agreement updates.                                                                                            |
| **Refunds**                                                                                                                                          | **Status Retrieval**                    | POST            | Enables the debtor service provider to provide the status of a payment.                                                                                                     |
| **Information Exchange Service**                                                                                                                     | **Request Creditor Alias Resolution**   | POST            | Enables a sending institution (DSP) to send creditor(recipient) alias to Mastercard for resolution.​                                                                        |
| **Information Exchange Service**                                                                                                                     | **Retrieve Creditor Service Providers** | GET             | Enables a sending institution (DSP) to retrieve list of receiving institutions (CSPs). This endpoint should be called once a day and the response should be cached by DSP.​ |

|                                                                                                                                                      |                                                   |                 |                                                                                                             |
|------------------------------------------------------------------------------------------------------------------------------------------------------|---------------------------------------------------|-----------------|-------------------------------------------------------------------------------------------------------------|
| **[Mastercard To DSP](https://developer.mastercard.com/account-to-account-commerce-for-dsp/documentation/api-reference/mastercard-to-dsp/index.md)** |                                                   |                 |                                                                                                             |
| **Feature**                                                                                                                                          | **APIs**                                          | **HTTP Method** | **Description**                                                                                             |
| **Payment Requests**                                                                                                                                 | **Payment Request Creation With Agreement**       | POST            | Enables the debtor service provider to receive a request for payment for a linked debtor account.           |
| **Payment Requests**                                                                                                                                 | **Payment Request Status Retrieval Request**      | POST            | Enables the debtor service provider to obtain the payment request details from Zapp.                        |
| **Agreements**                                                                                                                                       | **Agreement update**                              | POST            | Enables the debtor service providers to notify Mastercard for agreement updates.                            |
| **Refunds**                                                                                                                                          | **Refund Account Request**                        | POST            | Enabled the debtor service provider to provide debtor account details for refund purpose.                   |
| **Refunds**                                                                                                                                          | **Refund Payment Confirmation**                   | POST            | Enables the debtor service provider to receive confirmation of a refund transaction.                        |
| **Information Exchange Service**                                                                                                                     | **Alias resolution update with creditor details** | POST            | Enables Mastercard to provide resolved creditor (recipient) alias details to the sending institution (DSP). |