Building a rogue, and the description tells me Key Ability should only be Dex, unless a Racket gives another option. I chose the thief racket, which should not provide any extra options, but when I go to select my Class Boost, which is also used to define the ability used for Class DC, I have the options of Strength, Dexterity, Intelligence, Wisdom, and Charisma.
Is this a bug/missing feature in Pathbuilder, or am I misunderstanding what it’s doing?
Is this just based on the player core or are you using a character builder app? Pathfinder generally provides a lot of flexibility in terms of which builds are viable. Without pulling out a book to check, I suspect that the “key ability” is more of a suggestion than requirement.