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Predicates and directives are proposed to extend the versatility and expressivityof a shape rule specification `language'. Specifically, a predicate serves toexpress a condition on the application of a parametric-associative shape rule thatcannot simply be explicated within the left-hand side shape. A directive, on theother hand, is a value specification that is required when applying aparametric-associative shape rule, where this value specification cannot bederived from or expressed within the right-hand-side shape. We discuss thebenefits of a set of predicates and directives to address seemingly simple requeststhat might actually be hard to express otherwise. Specifically, we elaborate on themotivation for introducing predicates and directives, and demonstrate the variouspredicates and directives in more detail, including their implementation.