Your observation is correct, Kendo UI Validator is an UI validator. The DataSource does not have build-in data validator. The validate settings that you set in the schema are applicable only for widgets with a build-in editor mode (e.g. they will not work with custom/template editors). The reason is that the UI validator works on the basis of validation attributes. When a custom editor is used, there is no way for the framework to know how the HTML will look like and respectively where to append the validation HTML attributes.
In your particular scenario, in order the validation to work as expected you should manually add required and name attribute to the editor input:
I hope this information will help.
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