public List<StructureShape> getErrors(ToShapeId operation) {
        return errors.getOrDefault(operation.toShapeId(), ListUtils.of());
    }
Gets the list of error structures defined on an operation.

<p>An empty list is returned if the operation is not found or
has no errors.

@param operation Operation to get the errors of.
@return Returns the list of error structures, or an empty list.
@see #getErrors(ToShapeId, ToShapeId) to get errors that inherit from a service.
smithy-model/src/main/java/software/amazon/smithy/model/knowledge/OperationIndex.java