boolean isRequiredToBePresent() {
            return true;
        }
Validates paginated traits.

<ul>
    <li>The inputToken and outputToken properties must be set when an
     operation's properties are optionally merged with a service's.</li>
    <li>The items property, if set, must reference a list or map
     output member.</li>
    <li>The pageSize property, if set, should reference an optional integer
     input member. It may, but should not reference an optional byte, short,
     or long.</li>
    <li>The inputToken property should reference an optional string input
     member. It may, but should not reference an optional map.</li>
    <li>The outputToken property should reference an optional string output
     member. It may, but should not reference an optional map.</li>
</ul>
smithy-model/src/main/java/software/amazon/smithy/model/validation/validators/PaginatedTraitValidator.java