Open Source API Clients

API Blueprint. A powerful high-level API description language for web APIs. API Blueprint is simple and accessible to everybody involved in the API lifecycle. Its syntax is concise yet expressive. With API Blueprint you can quickly design and prototype APIs to be created or document and test already deployed mission-critical APIs. API Blueprint is built to encourage dialogue and collaboration between project stakeholders, developers and customers at any point in the API lifecycle. At the same time, the API Blueprint tools provide the support to achieve the goals be it API development, governance or delivery. API Blueprint is completely open sourced under the MIT license. Its future is transparent and open. API Blueprint doesn't need a closed work group. Instead it uses the RFC process similar to Rust language or Django Enhancement Proposal RFC processes.

Bert Client is a standalone software for Windows that allows you to quickly and easily test REST API calls. It is an alternative to more complex tools like Postman, but is designed to be simple and straightforward, allowing you to make adhoc POST and GET requests and receive the response in a straightforward way. Bert Client is perfect for developers who want a lightweight and easy-to-use tool for testing their APIs. With Bert Client, you can quickly test your API endpoints without having to worry about setting up complex configurations or dealing with a steep learning curve. Bert Client supports sending requests with an Authorization token, making it easy to test APIs that require authentication. The response from the API is displayed in a user-friendly format, making it easy to see the results of your API calls.