From publisher blurb:
A little something extra for your PF2 game!
Spellcasters need additional choices to pursue concepts in critical success and failure where magic is concerned, and with Specialist Spells you'll find 8 new magics for specialists in the schools of magic, with spells up to 10th level spells so the most powerful casters can enhance their favorite schools of magic to reshape reality and exert control over their enemies and the world around them!
The new Pathfinder Second Edition has a ton of customizable options, and the Just a Second line gives you about a page of new rules content to incorporate into your campaign. A set of feats, linked spells, clever magic items, and so on. No fuss, no muss, just new ideas and mechanics for GMs and players alike!