# Developer Tools
source: https://developer.mastercard.com/presentment/documentation/developer-tools/index.md

## Overview {#overview}

Use this section to access practical tools for testing and integrating with the Offers for Publishers API. Start with the reference application for implementation examples, or use the Postman and Insomnia collections to send requests quickly.

* [Reference Application](https://developer.mastercard.com/presentment/documentation/developer-tools/reference-application/index.md)
* [Postman Collection](https://developer.mastercard.com/presentment/documentation/developer-tools/postman-collection/index.md)
* [Insomnia Collection](https://developer.mastercard.com/presentment/documentation/developer-tools/insomnia-collection/index.md)

## Next steps {#next-steps}

Proceed to the [Testing](https://developer.mastercard.com/presentment/documentation/testing/index.md) section to plan and execute Sandbox validation for the Offers for Publishers API. Review the recommended testing workflows for both positive and negative test scenarios.