# API Reference
source: https://developer.mastercard.com/commercial-event-notifications/documentation/parameters/index.md

## API Reference {#api-reference}

The Commercial Event Notifications API Reference comprises this summary page, on which you can browse and try out each API call, and pages with more detail on each resource - fieldmappings, subscriptions and notifications -
the actions you can perform on them and the parameters that are used.

You may also download the Open API Specification v3 (OAS3) definition file for the API that you can use to understand the API contract and
generate a client application.

API Specification: `https://static.developer.mastercard.com/content/commercial-event-notifications/swagger/event_notification_OAS3.yaml`

## Next Steps {#next-steps}

Now that you have a good understanding of all the services endpoints, proceed to the [Integration and Testing](https://developer.mastercard.com/commercial-event-notifications/documentation/integration-and-testing/index.md) section to learn about testing the service.