The Mystery's boost count (N). ≤ 0 contributes nothing.
Whether the associated skill already exists on the actor. An existing skill boosts off its seeded mastery level; an absent skill spends its first boost opening at Skill Base.
OptionalseedMLThe associated skill's seeded mastery-level base (before its own
permanent boosts and situational deltas). Required when hasSkill.
OptionalskillThe associated skill's Skill Base. Used to open an absent skill.
Required when !hasSkill.
Inputs for computeBoostContribution.