How to add meta keywords, description for menus created through modules dynamically?

We might face a requirement where we need to place the meta data for a page dynamically based on user activity. For eg., search pages.

We can use drupal_add_html_head to add meta data for a page.

    $pageKeywords = array(

        '#type' => 'html_tag',

        '#tag' => 'meta',

        '#attributes' => array(

            'name' => 'keywords',

            'content' => 'custom meta keywords',

        )

    );

    $pageDescription = array(

        '#type' => 'html_tag',

        '#tag' => 'meta',

        '#attributes' => array(

            'name' => 'description',

            'content' => 'custom meta description',

        )

    );

   $pageTitle = 'page title';

    drupal_add_html_head($pageKeywords, 'page_keywords');

    drupal_add_html_head($pageDescription, 'page_description');

    drupal_set_title($pageTitle);