For those using Emacs, I'd recommend restclient.el [1]. In Emacs fashion, you can keep REST API documented in a single (or more) files and evaluate parts directly in buffer for testing and playing. Throw that on git/mercurial and you have versioned and documented REST API ;)
Visual Studio Code has a similarly named (seemingly?) API-compatible extension: https://github.com/Huachao/vscode-restclient