Merge pull request #930 from kira1928/update-index.d.ts

Update index.d.ts

Author: abetomo

typings/index.d.ts

@@ -226,9 +226,10 @@ declare namespace local {
      * Set the description to `str`.
      *
      * @param {string} str
+     * @param {{[argName: string]: string}} argsDescription
      * @return {(Command | string)}
      */
-    description(str: string): Command;
+    description(str: string, argsDescription?: {[argName: string]: string}): Command;
     description(): string;
 
     /**