diff --git a/test/server/Test.interface.yaml b/test/server/Test.interface.yaml
index d015c99..7daea7d 100644
--- a/test/server/Test.interface.yaml
+++ b/test/server/Test.interface.yaml
@@ -3,3 +3,12 @@
 properties:
     - name: SomeValue
       type: int64
+    - name: ReadonlyValue
+      type: int64
+      flags:
+          - readonly
+          - emits_change
+    - name: ConstValue
+      type: int64
+      flags:
+          - const