diff --git a/package.json b/package.json
index dca1b0b..79ea10d 100644
--- a/package.json
+++ b/package.json
@@ -43,7 +43,7 @@
   "dependencies": {
     "@modelcontextprotocol/sdk": "^1.20.1",
     "cors": "^2.8.5",
-    "express": "^5.0.1",
+    "express": "^4.21.2",
     "express-rate-limit": "^7.5.0",
     "rimraf": "^6.0.1",
     "spawn-rx": "^4.0.0",