VS Code API - remote calls

I am currently investigating VS code extensions in conjunction with a code generation project. While I understand that the VS code API is fairly full-fledged to allow in-extension manipulation of documents I can't figure out how to do this outside of the extension.

Are there ways of remotely executing the vs code JavaScript APIs outside of vscode which in turn will drive the GUI.

I am trying to figure out if I can do any of the following:

• Execute the API JavaScript code when through the code cli
• Run a web server/socket within an extension to listen to events from external systems and execute the JS API accordingly
• If not socket/rest server, should I listen to filesystem changes and react accordingly?

Basically, what are the options for remote control driving of vs code?