does a short rest restore spell slots
The Best Warlock Spells By Level in D&D 5e
The warlock gets few spell slots, but they refresh every short rest and scale to the highest available level.
Baldur's Gate 3: How to rest | Rock Paper Shotgun
Level 1 Spell Slots → 38% * If you have max Spell Slots (4), you will recover 1 slot at first Short Rest, and 2 more slots at second Short Rest. 3 Spell Slots in total.
Warlock 5e: DnD 5th Edition Class Guide - RPGBOT
Equally as important though, the rod also gives you the ability to regain a spell slot as an action which, funnily enough, almost doubles your available spellcasting slots per every short rest.
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You can also fill up your Spell Slots via short rest, so after every fight make sure to short rest to keep this build having the spell slot fuel it needs.