magento2 – Magento 2 – How to add a required checkbox to the checkout by using uiComponents?

I try to add a new checkbox for the user agreements.

The checkbox is showing in the checkout fine, but it is not required.

Whats the official way to make it required?

THEMEMagento_Checkoutlayoutcheckout_index_index.xml

<?xml version="1.0"?>
<page xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:View/Layout/etc/page_configuration.xsd">
    <body>
        <referenceBlock name="checkout.root">
            <arguments>
                <argument name="jsLayout" xsi:type="array">
                    <item name="components" xsi:type="array">
                        <item name="checkout" xsi:type="array">
                            <item name="children" xsi:type="array">
                                <item name="sidebar" xsi:type="array">
                                    <item name="children" xsi:type="array">
                                        <item name="additional" xsi:type="array">
                                             <item name="children" xsi:type="array">
                                                <item name="checkboxes" xsi:type="array">
                                                    <item name="children" xsi:type="array">
                                                        <item name="user_agreement_checkbox_container" xsi:type="array">
                                                            <item name="component" xsi:type="string">Magento_Checkout/js/view/additional/user_agreement</item>
                                                            <item name="description" xsi:type="string" translate="true">Accept User Agreement</item>
                                                            <!--<item name="dataScope" xsi:type="string">amcheckout.additional.user_agreement</item>-->
                                                            <item name="provider" xsi:type="string">checkoutProvider</item>
                                                            <item name="checked" xsi:type="boolean">false</item>
                                                        </item>
                                                    </item>
                                                </item>
                                            </item>
                                        </item>
                                    </item>
                                </item>
                            </item>
                        </item>
                    </item>
                </argument>
            </arguments>
        </referenceBlock>
    </body>
</page>

THEME/Magento_Checkout/js/view/additional/user_agreement

define((
    'jquery',
    'Magento_Ui/js/form/element/single-checkbox'
), function ($,  SingleCheckbox) {
    'use strict';

    return SingleCheckbox.extend({
        defaults: {
            valueMap: {
                'true': true,
                'false': false
            }
        }
    });
});