CritiqueBrainz is a repository for Creative Commons licensed reviews.
Documentation is available at https://critiquebrainz.readthedocs.org/.
In case you want to build documentation yourself follow the following steps (make sure that you use Python 3):
$ cd ./docs
$ pip3 install -r requirements.txt
$ make html
After that open ./docs/_build/html/index.html in your favourite browser.