the one used for lessonshop, test your url at https://developers.facebook.com/tools/debug/

meta_template.html

        <title>LessonShop.net</title>
        <meta charset="utf-8">
        <meta content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=0" name="viewport" />
        <meta property="og:url" content="https://lessonshop.net" />
        <meta property="og:title" content="LessonShop.net" />
        <meta property="og:type" content="website" />
        <meta property="og:description" content="Lessonshop is a lesson bookings marketplace that allows you to effortlessly take or teach lessons." />
        <meta property="og:image" content="https://s3.amazonaws.com/lessonshop.net/other/the_logo_300_new.jpg" />
        <meta property="fb:app_id" content="1515460021880400" />
        <meta name="description" content="Lessonshop is a lesson bookings marketplace that allows you to effortlessly take or teach lessons." />
        <link rel="shortcut icon" type="image/x-icon" href="/the_actual_code/favicon.ico" />

Super 💯