An action with this trait requires a degree of mental concentration and discipline.
Manipulate
You must physically manipulate an item or make gestures to use an action with this trait. Creatures without a suitable appendage can’t perform actions with this trait. Manipulate actions often trigger reactions.
Spellshape
Actions with the spellshape trait tweak the properties of your spells. You must use a spellshape action directly before casting the spell you want to alter. If you use any action (including free actions and reactions) other than casting a spell directly after, you waste the benefits of the spellshape action. Any additional effects added by a spellshape action are part of the spell's effect, not of the spellshape action itself.
You can perform multiple compositions simultaneously, typically by performing in multiple ways at the same time, using special vocal techniques to double your voice, or creating occult magic that replicates your song or speech. If your next action is to cast a composition, it becomes a harmonized composition. Unlike a normal composition, a harmonized composition doesn’t end if you cast another composition, and you can cast another composition on the same turn as a harmonized one. Casting another harmonized composition ends any harmonized composition you already have in effect.