diff --git a/lib/rgrb/plugin/url_fetch_title/generator.rb b/lib/rgrb/plugin/url_fetch_title/generator.rb
index 261f8646..cfe9058b 100644
--- a/lib/rgrb/plugin/url_fetch_title/generator.rb
+++ b/lib/rgrb/plugin/url_fetch_title/generator.rb
@@ -17,10 +17,10 @@ module UrlFetchTitle
       class Generator
         include ConfigurableGenerator
 
-        # HTTP ステータスコード
+        # HTTP ステータスの Reason-Phrase
         # @see https://www.iana.org/assignments/http-status-codes/http-status-codes-1.csv
         # @see http://tools.ietf.org/html/rfc7231#section-6
-        HTTP_STATUS_CODES = {
+        HTTP_STATUS_REASON_PHRASE = {
           100 => 'Continue',
           101 => 'Switching Protocols',
           102 => 'Processing',
@@ -80,62 +80,87 @@ class Generator
           511 => 'Network Authentication Required'
         }
 
-        def initialize(*args)
-          super
-
-          @agent = Mechanize.new
-          @agent.user_agent = "RGRB/#{RGRB::VERSION} (Creator's Network IRC bot)"
-        end
-
         def configure(config_data)
           @no_ssl_verify = config_data['NoSSLVerify'] || []
-          @agent.open_timeout = config_data['OpenTimeout']
-          @agent.read_timeout = config_data['ReadTimeout']
+          @open_timeout = config_data['OpenTimeout']
+          @read_timeout = config_data['ReadTimeout']
           @reply_prefix = config_data['ReplyPrefix'] || 'Fetch title: '
           @reply_suffix = config_data['ReplySuffix'] || ''
         end
 
         # 誰かが発言した URL にアクセスし、ページの title タグを取得する
-        # @param [String] タイトルを取得するページのURL
+        # @param [String] url タイトルを取得するページのURL
         # @return [String] 取得したタイトル
         def fetch_title(url)
-          if no_ssl_verify?(url)
-            @agent.verify_mode = OpenSSL::SSL::VERIFY_NONE
-          end
+          agent = new_agent(url)
+          body =
+            begin
+              page = agent.get(url)
 
-          begin
-            page = @agent.get(url)
-            body =
               if page.respond_to?(:title)
                 page.title
               else
-                response = page.response
-                contents = [
-                  response['Content-Type'],
-                  response['Content-Length'].to_i.to_s(:human_size)
-                ]
-                "(#{contents.join('; ')})"
+                http_header_to_body(page.response)
               end
-          rescue SocketError
-            body = '(サーバーに接続できませんでした)'
-          rescue Net::HTTP::Persistent::Error
-            body = '(タイムアウト)'
-          rescue Mechanize::ResponseCodeError => response_code_error
-            response_code = response_code_error.response_code.to_i
-            reason_phrase =
-              if HTTP_STATUS_CODES.has_key?(response_code)
-                HTTP_STATUS_CODES[response_code]
-              else
-                '不明なエラー'
-              end
-            body = "(#{response_code} #{reason_phrase})"
-          end
+            rescue SocketError
+              '(サーバーに接続できませんでした)'
+            rescue Net::HTTP::Persistent::Error
+              '(タイムアウト)'
+            rescue Mechanize::ResponseCodeError => response_code_error
+              response_code_to_body(response_code_error.response_code.to_i)
+            end
 
           "#{@reply_prefix}#{body}#{@reply_suffix}"
         end
 
+        # HTTP ヘッダをメッセージに変換する
+        # @param [Mechanize::Headers] header HTTP ヘッダ
+        # @return [String]
+        def http_header_to_body(header)
+          contents = [
+            header['Content-Type'],
+            header['Content-Length'].to_i.to_s(:human_size)
+          ]
+
+          "(#{contents.join('; ')})"
+        end
+        private :http_header_to_body
+
+        # HTTP ステータスコードをメッセージに変換する
+        # @param [Fixnum] response_code HTTP ステータスコード
+        # @return [String]
+        def response_code_to_body(response_code)
+          reason_phrase =
+            if HTTP_STATUS_REASON_PHRASE.key?(response_code)
+              HTTP_STATUS_REASON_PHRASE[response_code]
+            else
+              '不明なエラー'
+            end
+
+          "(#{response_code} #{reason_phrase})"
+        end
+        private :response_code_to_body
+
+        # 新しいエージェントを作り、設定して返す
+        # @param [String] url タイトル取得元の URL
+        # @return [Mechanize]
+        def new_agent(url)
+          agent = Mechanize.new
+          agent.user_agent =
+            "RGRB/#{RGRB::VERSION} (Creators Network IRC bot)"
+          agent.open_timeout = @open_timeout
+          agent.read_timeout = @read_timeout
+
+          if no_ssl_verify?(url)
+            agent.verify_mode = OpenSSL::SSL::VERIFY_NONE
+          end
+
+          agent
+        end
+        private :new_agent
+
         # 与えられた URL が、自己署名証明書を許可するドメインか調べる
-        # @param [String] 調べる URL
+        # @param [String] url 調べる URL
         # @return [Boolean]
         def no_ssl_verify?(url)
           hostname = URI.parse(url).hostname