Walking this back, the API only allows setting this up for app bundles, which adds another layer of complexity I'm not down for. I want it to be a CLI tool, it doesn't need a helper or any other layers.

As a kind of apology, I made a drop-in hammerspoon config that should accomplish exactly what you wanted: https://gist.github.com/philocalyst/ad9f6d7cc08a9cdefa795e1b...

And if you've never used it before: https://www.hammerspoon.org/go/