$ gem help commands
Output ``` GEM commands are: build Build a gem from a gemspec cert Manage RubyGems certificates and signing settings check Check a gem repository for added or missing files cleanup Clean up old versions of installed gems contents Display the contents of the installed gems dependency Show the dependencies of an installed gem environment Display information about the RubyGems environment fetch Download a gem and place it in the current directory generate_index Generates the index files for a gem server directory help Provide help on the 'gem' command info Show information for the given gem install Install a gem into the local repository list Display local gems whose name matches REGEXP lock Generate a lockdown list of gems mirror Mirror all gem files (requires rubygems-mirror) open Open gem sources in editor outdated Display all gems that need updates owner Manage gem owners of a gem on the push server pristine Restores installed gems to pristine condition from files located in the gem cache push Push a gem up to the gem server query Query gem information in local or remote repositories rdoc Generates RDoc for pre-installed gems search Display remote gems whose name matches REGEXP server Documentation and gem repository HTTP server signin Sign in to any gemcutter-compatible host. It defaults to https://rubygems.org signout Sign out from all the current sessions. sources Manage the sources and cache file RubyGems uses to search for gems specification Display gem specification (in yaml) stale List gems along with access times uninstall Uninstall gems from the local repository unpack Unpack an installed gem to the current directory update Update installed gems to the latest version which Find the location of a library file you can require yank Remove a pushed gem from the index For help on a particular command, use 'gem help COMMAND'. Commands may be abbreviated, so long as they are unambiguous. e.g. 'gem i rake' is short for 'gem install rake'. ```