In the current version (windows console fccb09f), the toolbox item is not usable in construction tasks.
I would guess that this has to do with the system being largely untouched since WhalesCata, and thus not migrated to tool qualities?
Seconded.
also can someone direct me to where I can look at the code for construction and for crafting? if they’re similar enough I might be able to prebuild the modifications myself so all a developer has to do is submit them.
I just merged Rivet’s fix about an hour ago. Thanks for reporting.
the crafting code is in crafting.cpp, and the construction code is in construction.cpp
if you mean the data, that’s in data/json/recipes/recipes.json (yay redundancy) and data/json/construction.json (not as sure of that one)
The Toolbox isn’t usable when Installing items in a vehicle, it calls for a seperate wrench.
Edit: Can’t be used to Uninstall either.
Fixed about 10 seconds ago, thanks for reporting. 
The toolbox only has level 1 hammering quality, an actual hammer has 3 (and many recipes require 2+).