Graph Developer Proxy allows developers to test their Microsoft Graph applications locally by simulating Microsoft Graph API errors and mocking Microsoft Graph API responses. Credit: Shutterstock With Microsoft Graph Developer Proxy, the software giant is providing a command line tool intended to provide a better way to test applications that use Microsoft Graph. Graph Developer Proxy, currently in a developer preview, allows developers to mock Graph API responses and simulate Graph API errors on their local machines. Issues can be identified and fixed in code early in the development cycle. The current preview focuses on error simulation for Microsoft Graph and other APIs, as well as on providing contextual guidance to improve application performance. Published January 4, the latest preview release, version 0.3, can be downloaded from GitHub. It is available for Windows, macOS, and Linux. Users are advised to check if apps properly handle API errors. The Microsoft Graph API provides access to data and insights from Microsoft 365 applications. By extending requests to Microsoft Graph with the $select query parameter, developers can limit the data that Microsoft Graph returns to just what is needed by their application, speeding up the API response. Graph Developer Proxy will warn users of any requests to the Graph API that do not use the $select parameter and provide a link to guidance with more information about using the $select parameter. For the future, Microsoft is refactoring Graph Developer Proxy to be more modular, making it easier to maintain features and providing the opportunity for developer-driven plugin support for specific scenarios. Future plans also call for improving the readability of the proxy’s output, and for investigating ways to understand which beta endpoints are being used in applications so these can be upgraded to use the version 1.0 endpoints that are supported in production. APIsMicrosoft .NETSoftware DevelopmentCloud Computing