Yes it is possible. You must specify the URL where your server serves the pages you want to check. For example, if you use rspec, just do it in spec_helper.rb. In addition, you need to specify another driver that does not want to run the application (which is not), for example selenium:
Capybara.app_host = 'http://www.site-to-test.com'
Capybara.default_driver = :selenium
The base Gemfilewill look like this:
source 'https://rubygems.org'
gem "rspec", '~> 3.0'
gem "capybara"
gem "selenium-webdriver", '~> 2.45'
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