diff --git a/src/main/java/com/ntlab/irisserver/resources/GameStateRest.java b/src/main/java/com/ntlab/irisserver/resources/GameStateRest.java
index f7ef346..c165c65 100644
--- a/src/main/java/com/ntlab/irisserver/resources/GameStateRest.java
+++ b/src/main/java/com/ntlab/irisserver/resources/GameStateRest.java
@@ -8,6 +8,8 @@
 import javax.ws.rs.GET;
 import javax.ws.rs.Path;
 import javax.ws.rs.PathParam;
+import javax.ws.rs.Produces;
+import javax.ws.rs.core.MediaType;
 import java.util.List;
 
 @Component
@@ -16,6 +18,7 @@
 public class GameStateRest {
     @Path("/{rid}/game/opens")
     @GET
+    @Produces(MediaType.APPLICATION_JSON)
     public List<Boolean> getOpens(@PathParam("rid") String rid){
         RoomManager rm = RoomManager.getInstance();
         Room room = rm.getRoom(rid);
@@ -26,6 +29,7 @@
 
     @Path("/{rid}/game/turn")
     @GET
+    @Produces(MediaType.APPLICATION_JSON)
     public String getTurn(@PathParam("rid") String rid) {
         RoomManager rm = RoomManager.getInstance();
         Room room = rm.getRoom(rid);