This is really cool. I had a similar idea a couple of years ago to implement something similar to this using the three finger single tap command on the trackpad that currently brings up dictionary/siri knowledge/wikipedia etc. I see you have 4-finger tap implemented with an additional app which is really cool and probably better than the 3-finger native OS way since you can highlight/copy as well as build your own menu.
* Converting seconds-from-epoch to a human readable date
* Select an id and pull info about it
At first, I tried to perform these mechanical tasks with some crazy shortcuts. But remembering shortcuts for every little flow is heavy.
Eventually, I've built a programmable tooltip on Mac OS X for these mechanical tasks.
I'd love for you to try it!
https://github.com/tanin47/tip