# Insomnia Collection
source: https://developer.mastercard.com/eligibility-api/documentation/developer-tools/insomnia-collection/index.md

Use Insomnia to test Mastercard APIs with a ready-made workflow for importing requests, configuring environments, and validating calls in Sandbox or Production.

For the full step-by-step instructions, see the [Insomnia tutorial](https://developer.mastercard.com/platform/tutorial/use-insomnia-for-mastercard-apis/).

## Overview {#overview}

The Insomnia guide covers how to set up Mastercard API requests in Insomnia, including plugin installation, workspace import options, environment configuration, and request execution.

## Prerequisites {#prerequisites}

* Access to a Mastercard Developers project with the credentials required by the API you are testing
* Insomnia installed on your machine
* The correct authentication and encryption details for the service you want to call
* The Insomnia collection for the Mastercard API you want to test
* The Insomnia environment for the Mastercard API you want to test

## What you will find {#what-you-will-find}

* Plugin installation options for Insomnia
* Import guidance for collections and workspace templates
* Environment setup for OAuth 1.0a, OAuth 2.0, and JWE-enabled flows
* Practical steps for sending and validating requests in Sandbox and Production