<Operation Class="NQualityOfLife.XML.Math">
    <xpath>string</xpath>
    <value1>string</value1>
    <operation>Operator</operation> <!-- Invalid -->
    <value2>string</value2>
    <applyVariables>bool</applyVariables> <!-- true -->
    <toVar>string</toVar> <!-- Optional -->
    <done Class="PatchOperation"> <!-- Optional -->

    </done>
    <error Class="PatchOperation"> <!-- Optional -->

    </error>
</Operation>