diff --git a/src/github.com/matrix-org/dendrite/clientapi/routing/voip.go b/src/github.com/matrix-org/dendrite/clientapi/routing/voip.go
index d3212c4ed..e699a91f2 100644
--- a/src/github.com/matrix-org/dendrite/clientapi/routing/voip.go
+++ b/src/github.com/matrix-org/dendrite/clientapi/routing/voip.go
@@ -36,6 +36,8 @@ type turnServerResponse struct {
 	TTL int `json:"ttl"`
 }
 
+// RequestTurnServer implements:
+//     GET /voip/turnServer
 func RequestTurnServer(req *http.Request, device *authtypes.Device, cfg config.Dendrite) util.JSONResponse {
 	turnConfig := cfg.TURN