Visual Studio Code has several editor integrations for using Flow.
Flow Language Support provides all the functionality you would expect — linting, intellisense, type tooltips and click-to-definition. It’s stable and under active development. However, it currently lacks on-the-fly linting and only shows you type errors after you save a file.
Other extensions that you may try are:
© 2013–present Facebook Inc.
Licensed under the BSD License.