Visual Studio: Code

Mason integrates fairly nicely with Visual Studio: Code. With the full suite of options, Code offers manifest.json and project.yaml IntelliSense (auto-completion with descriptions and examples), build and pack tasks, and errors appear directly within the text files. The necessary files can be found in the quickstart repository, but you might as well just download the entire repository if you choose to use the files.

Tasks are organized as build tasks, meaning CTRL + SHIFT + B (by default) prompts you with a list of options. Running one of them will either succeed, or bring focus to the problems panel. Problems will be underlined when possible in files, and Mason must be re-ran to update its reported problems.