diff --git a/API/I18N/ja.json b/API/I18N/ja.json
index 384986fcf..9a903c892 100644
--- a/API/I18N/ja.json
+++ b/API/I18N/ja.json
@@ -1,3 +1,4 @@
 {
-    "chapter-num": "章 {0}"
+    "chapter-num": "章 {0}",
+    "invalid-token": "無効トークン"
 }