You could almost get a crown for that answer.
Fret crowning tool. https://www.guitarbuilding.solutions/product-page/luthier-tools-fret-crowning-tool
Interesting
It looks like a whole other world.... https://www.stewmac.com/Luthier_Tools/Types_of_Tools/
See, it’s physically impossible for guitars and some other fretted instruments to have a perfect pitch at every fret due to its design - opposite to the piano, for example...
Unless you have one of those ones with the funny frets...I was just reading last night about how the manufacturers don't bother setting up lower-end guitars properly these days.
... meanwhile I am watching videos and reading up on how to get my Strat's floating bridge set up properly.
Some might argue it can be used to assist in theft
It's not particularly sharp.
with one you would be expected to know your bridge from your brace.
There are at least three more clues in my post