simple-custom-meta-box.php

/**
 * Adds a meta box
 */
function simple_meta_box() {
    add_meta_box( 'prfx_meta', ( 'View Post' ), 'simple_meta_box_callback', 'staff', 'side', 'high' );
}
add_action( 'add_meta_boxes', 'simple_meta_box' );

/**
 * Outputs the content of the meta box
 */
function simple_meta_box_callback( $post ) {
    echo '<a href="';
    the_permalink();
    echo '" class="button button-small" target="_blank">View Profile</a>';
}