code: func cmdSearch(params Parameters) *subcommands.Command {
  	return &subcommands.Command{
  		UsageLine: "search <package> -tag key:value [options]",
  		ShortDesc: "searches for package instances by tag",
  		LongDesc:  "Searches for instances of some package with all given tags.",
  		CommandRun: func() subcommands.CommandRun {
  			c := &searchRun{}
  			c.registerBaseFlags()
  			c.clientOptions.registerFlags(&c.Flags, params, withoutRootDir)
  			c.tagsOptions.registerFlags(&c.Flags)
  			return c
  		},
  	}
  }
docs: ////////////////////////////////////////////////////////////////////////////////
  // 'search' subcommand.