>
        <ref>String</ref>
        <p>
          The URL of a page containing documentation associated with this error.
        </p>
      </field>
      <field name="contextMessages" optional="true">
        <list>
          <ref>DiagnosticMessage</ref>
        </list>
        <p>
          Additional messages associated with this diagnostic that provide
          context to help the user understand the diagnostic.
        </p>
      </field>
      <field name="hasFix" optional="true">
        <ref>bool</