Display Taxonomy Description on edit-tags screen?

The code for where you’ve circled can be found in wp-admin/edit-tags.php:295

You’ll notice there’s nothing there. No hooks, no filters. You’re out of luck for tapping into that cleanly.

Luckily you can do a duct tape method to still add it with jQuery. You can dynamically put text where you’ve circled by doing something like:

add_action( 'admin_head', function(){
    global $wp_query;
    $screen = get_current_screen();
    if ($screen->base == 'edit-tags' || $screen->base == 'term') {
        $mytax = get_taxonomy($screen->taxonomy);
        if (!empty($mytax->description)) {
            ?>
            <script>
            jQuery(window).load(function() {
                jQuery('.wrap h1').after("<p class="description"><?php echo $mytax->description ?></p>");
            });
            </script>
            <?php
        }
    }
});

---

UPDATE

As you pointed out @Slam, you can use the _pre_add_form and _term_edit_form_top hooks to show the into around the area you’re after. To do that, you can cycle through all the taxonomies and dynamically run the actions like so:

add_action( 'admin_init', function(){
    $taxonomies = get_taxonomies(); 
    foreach ( $taxonomies as $taxonomy ) {
        add_action("{$taxonomy}_pre_add_form", 'my_plugin_tax_description');
        add_action("{$taxonomy}_term_edit_form_top", 'my_plugin_tax_description');
    }
});

function my_plugin_tax_description() {
    global $wp_query;
    $screen = get_current_screen();
    if ($screen->base == 'edit-tags' || $screen->base == 'term') {
        $mytax = get_taxonomy($screen->taxonomy);
        if (!empty($mytax->description))
            echo "<p class="description">{$mytax->description}</p>";
    }
}

Although _pre_add_form fires in the left column – not directly below the h1 title.