diff --git a/rcli/tcp.go b/rcli/tcp.go
index 7aa228afc9..0a06d459ce 100644
--- a/rcli/tcp.go
+++ b/rcli/tcp.go
@@ -53,6 +53,9 @@ func ListenAndServe(proto, addr string, service Service) error {
 	return nil
 }
 
+
+// Parse an rcli call on a new connection, and pass it to `service` if it
+// is valid.
 func Serve(conn io.ReadWriter, service Service) error {
 	r := bufio.NewReader(conn)
 	var args []string
diff --git a/rcli/types.go b/rcli/types.go
index b36aa75e8c..10a2938f37 100644
--- a/rcli/types.go
+++ b/rcli/types.go
@@ -1,5 +1,12 @@
 package rcli
 
+// rcli (Remote Command-Line Interface) is a simple protocol for...
+// serving command-line interfaces remotely.
+//
+// rcli can be used over any transport capable of a) sending binary streams in
+// both directions, and b) capable of half-closing a connection. TCP and Unix sockets
+// are the usual suspects.
+
 import (
 	"fmt"
 	"io"