Capricious

Meaning: You probably already know the meaning of this word, but Cotgrave defines caprice as:

A humor, caprichio, giddie thought, fantasticall conceit; a suddaine will, desire, or purpose to doe a thing, for which one hath no (apparent) reason.

I rather like the cynicism of that (apparent). Caprichio was a synonym for caprice, but now survives only in music.

Usefulness: 1 (Although if you wish to substitute giddie thought from now on, I won't blame you.)

Logofascination: 1 (It's a goat word! Probably! In fact, according to etymonline it's either from the Latin for wild goat, or a word about people with curly hair, and how can you not love that? I had a lightbulb moment when someone at work used it this week, and unlike a lot of etymological lightbulbs, this one was correct! Probably! Goats have a suprisingly strong influence on etymology, so I'm erring in their favour.)

In the wild: Yes, but according to Google its relative popularity has been reducing since a peak in the late 1700s.

Degrees: 1

Connections: n/a

Which is used in: G&P, three times, but in this instance it appears in Book the Third, XXXVIII: How Triboulet is set forth and blazed by Pantagruel and Panurge.  I mentioned the cod chapters recently; in this chapter Rabelais lists - and Sir Thomas expands - various praises of the fool Triboulet.

Egregious f.
Annual f.
Humourous and capricious f.
Festival f.
Rude, gross, and absurd f.
Recreative f.
Large-measured f.

Note that as with the cod chapter, fool is abbreviated to its initial. While written as praise, this chapter is also a useful source if you're ever after a good bdelygmia.