diff --git a/readline/prompt.go b/readline/prompt.go
index b1d4c48..64124cc 100644
--- a/readline/prompt.go
+++ b/readline/prompt.go
@@ -14,6 +14,7 @@ func (rl *Instance) SetPrompt(s string) {
 	rl.computePrompt()
 }
 
+// SetRightPrompt sets the right prompt.
 func (rl *Instance) SetRightPrompt(s string) {
 	rl.rightPrompt = s
 	rl.computePrompt()