Function check_constraints 

pub fn check_constraints(
    constraints: &[Constraint],
    fulfillment: &Fulfillment,
    strictness: StrictnessMode,
    mode: MandateMode,
) -> Vec<ConstraintCheckResult>

Evaluate all constraints against fulfillment data.

mode decides how an unrecognized constraint is treated. Autonomous is the open-mandate case, where the agent acts on its own and an unevaluable constraint would leave its authority unbounded, so such a constraint is a violation whatever the strictness setting says.