docs: function(name) {
      var command;
      if (name) {
        command = this.commands[name] = {
          name: name,
          specs: {}
        };
      }
      else {
        command = this.fallback = {
          specs: {}
        };
      }
  
      // facilitates command('name').options().cb().help()
      var chain = {
        options : function(specs) {
          command.specs = specs;
          return chain;
        },
        opts : function(specs) {
          // old API
          return this.options(specs);
        },
        option : function(name, spec) {
          command.specs[name] = spec;
          return chain;
        },
        callback : function(cb) {
          command.cb = cb;
          return chain;
        },
        help : function(help) {
          command.help = help;
          return chain;
        },
        usage : function(usage) {
          command._usage = usage;
          return chain;
        }
      };
      return chain;
    }