An action roll that specifies which character trait applies to it is called a trait roll. In the text of a feature or effect, a trait roll is referenced with the format "[Trait] Roll (Difficulty)" (e.g., "Agility Roll (12)"). If the text of an effect doesn't specify a trait roll's Difficulty, the GM sets the Difficulty based on the circumstances.
Features and effects that affect a trait roll also affect any action roll that uses the same trait, including attack rolls, Spellcast rolls, and standard action rolls.
Example: The katari's ancestry feature "Feline Instincts," which allows the katari to reroll an Agility Roll, can also be used on a standard action roll using Agility to traverse dangerous terrain or on an attack roll made with a weapon that uses Agility.