Add Relative Path to Max Search Path in Javascript?

I'm working on a Max Patch which will find json files in subfolders of the folder the .maxpat file lives in.

For instance, there might be a folder called videos.

In my js file I've made my way to the this.max.paths object, which one would think would be useful in adding folders to the search path, but I can't quite figure out how.

If anyone has any advice I would be very grateful. My goal here is to do this within javascript, without adding any objects to the patcher.

Thanks!