Doc comments work best as complete sentences, which allow a wide variety of automated presentations. The first sentence should be a one-sentence summary that starts with the name being declared.
If every doc comment begins with the name of the item it describes, you can use the doc subcommand of the go tool and run the output through grep.
See https://golang.org/doc/effective_go.html#commentary for more information on how to write good documentation.
package main
// This struct represents an cybernetically enhanced duck
type Duck struct {
}
package main
// Duck represents an cybernetically enhanced duck
type Duck struct {
}