Installing this module will result in watchdog notices whenever a cache tag is invalidated on your site (see screenshot). There is no configuration, just install and it will work.

N.B. Not recommended for production sites, this is a developer tool.

To make your Drupal 8 site as good as it can be it is a really good idea to utilise cache tags fully.

You may be familiar with examining cache tags on your pages by turning on 'debug_cacheability_headers' in services.yml.