diff --git a/client/internal/httpsender.go b/client/internal/httpsender.go
index a8f6c67..18f1f0d 100644
--- a/client/internal/httpsender.go
+++ b/client/internal/httpsender.go
@@ -276,6 +276,7 @@ func (h *HTTPSender) receiveResponse(ctx context.Context, resp *http.Response) {
 }
 
 func (h *HTTPSender) SetHeartbeatInterval(duration time.Duration) {
+	// 0 is invalid for a http sender
 	if duration != 0 {
 		h.SetPollingInterval(duration)
 	}
diff --git a/client/internal/wssender.go b/client/internal/wssender.go
index c05951d..03a65cf 100644
--- a/client/internal/wssender.go
+++ b/client/internal/wssender.go
@@ -73,7 +73,7 @@ func (s *WSSender) StoppingErr() error {
 	return s.err
 }
 
-// SetHeartbeatInterval ...
+// SetHeartbeatInterval sets the heartbeat interval and triggers timer reset.
 func (s *WSSender) SetHeartbeatInterval(d time.Duration) {
 	s.heartbeatIntervalSeconds.Store(int64(d.Seconds()))
 	select {