    # File lib/chef/formatters/error_inspectors/run_list_expansion_error_inspector.rb, line 36
            def add_explanation(error_description)
              case exception
              when Errno::ECONNREFUSED, Timeout::Error, Errno::ETIMEDOUT, SocketError
                error_description.section("Networking Error:","\#{exception.message}\n\nYour chef_server_url may be misconfigured, or the network could be down.\n")
              when Net::HTTPServerException, Net::HTTPFatalError
                humanize_http_exception(error_description)
              when Chef::Exceptions::MissingRole
                describe_missing_role(error_description)
              else
                error_description.section("Unexpected Error:","#{exception.class.name}: #{exception.message}")
              end
            end