grape-swaggerでgrapeでつくったAPIのドキュメントを自動生成する ref: http://qiita.com/kazuph/items/7a63d1cf22f2c6ab509d

api.rb

desc "Reserve a virgin in heaven", {
  :notes => <<-NOTE
    Virgins in heaven
    -----------------

    > A virgin doesn't come for free

    If you want to reserve a virgin in heaven, you have to do
    some crazy stuff on earth.

        def do_good
          puts 'help people'
        end

    * _Will go to Heaven:_ Probably
    * _Will go to Hell:_ Probably not
  NOTE
}

file0.txt

  # Documentation
  gem 'grape-swagger'
  gem 'grape-swagger-ui'

file2.txt

bundle install
rails s