diff --git a/package-lock.json b/package-lock.json
index a80dcb27..5ab2ecb5 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -25,7 +25,7 @@
         "openapi-fetch": "^0.14.0",
         "simple-oauth2": "^5.1.0",
         "yargs-parser": "^22.0.0",
-        "zod": "^3.25.76"
+        "zod": "^4.0.5"
       },
       "bin": {
         "mongodb-mcp-server": "dist/index.js"
@@ -1924,6 +1924,16 @@
         "mcp-inspector-client": "bin/start.js"
       }
     },
+    "node_modules/@modelcontextprotocol/inspector-client/node_modules/zod": {
+      "version": "3.25.76",
+      "resolved": "https://registry.npmjs.org/zod/-/zod-3.25.76.tgz",
+      "integrity": "sha512-gzUt/qt81nXsFGKIFcC3YnfEAx5NkunCfnDlvuBSSFS02bcXu4Lmea0AFIUwbLWxWPx3d9p8S5QoaujKcNQxcQ==",
+      "dev": true,
+      "license": "MIT",
+      "funding": {
+        "url": "https://github.com/sponsors/colinhacks"
+      }
+    },
     "node_modules/@modelcontextprotocol/inspector-server": {
       "version": "0.16.1",
       "resolved": "https://registry.npmjs.org/@modelcontextprotocol/inspector-server/-/inspector-server-0.16.1.tgz",
@@ -1941,6 +1951,26 @@
         "mcp-inspector-server": "build/index.js"
       }
     },
+    "node_modules/@modelcontextprotocol/inspector-server/node_modules/zod": {
+      "version": "3.25.76",
+      "resolved": "https://registry.npmjs.org/zod/-/zod-3.25.76.tgz",
+      "integrity": "sha512-gzUt/qt81nXsFGKIFcC3YnfEAx5NkunCfnDlvuBSSFS02bcXu4Lmea0AFIUwbLWxWPx3d9p8S5QoaujKcNQxcQ==",
+      "dev": true,
+      "license": "MIT",
+      "funding": {
+        "url": "https://github.com/sponsors/colinhacks"
+      }
+    },
+    "node_modules/@modelcontextprotocol/inspector/node_modules/zod": {
+      "version": "3.25.76",
+      "resolved": "https://registry.npmjs.org/zod/-/zod-3.25.76.tgz",
+      "integrity": "sha512-gzUt/qt81nXsFGKIFcC3YnfEAx5NkunCfnDlvuBSSFS02bcXu4Lmea0AFIUwbLWxWPx3d9p8S5QoaujKcNQxcQ==",
+      "dev": true,
+      "license": "MIT",
+      "funding": {
+        "url": "https://github.com/sponsors/colinhacks"
+      }
+    },
     "node_modules/@modelcontextprotocol/sdk": {
       "version": "1.15.1",
       "resolved": "https://registry.npmjs.org/@modelcontextprotocol/sdk/-/sdk-1.15.1.tgz",
@@ -1973,6 +2003,24 @@
         "node": ">=16.20.0"
       }
     },
+    "node_modules/@modelcontextprotocol/sdk/node_modules/zod": {
+      "version": "3.25.76",
+      "resolved": "https://registry.npmjs.org/zod/-/zod-3.25.76.tgz",
+      "integrity": "sha512-gzUt/qt81nXsFGKIFcC3YnfEAx5NkunCfnDlvuBSSFS02bcXu4Lmea0AFIUwbLWxWPx3d9p8S5QoaujKcNQxcQ==",
+      "license": "MIT",
+      "funding": {
+        "url": "https://github.com/sponsors/colinhacks"
+      }
+    },
+    "node_modules/@modelcontextprotocol/sdk/node_modules/zod-to-json-schema": {
+      "version": "3.24.6",
+      "resolved": "https://registry.npmjs.org/zod-to-json-schema/-/zod-to-json-schema-3.24.6.tgz",
+      "integrity": "sha512-h/z3PKvcTcTetyjl1fkj79MHNEjm+HpD6NXheWjzOekY7kV+lwDYnHw+ivHkijnCSMz1yJaWBD9vu/Fcmk+vEg==",
+      "license": "ISC",
+      "peerDependencies": {
+        "zod": "^3.24.1"
+      }
+    },
     "node_modules/@mongodb-js/device-id": {
       "version": "0.3.1",
       "resolved": "https://registry.npmjs.org/@mongodb-js/device-id/-/device-id-0.3.1.tgz",
@@ -13683,22 +13731,13 @@
       }
     },
     "node_modules/zod": {
-      "version": "3.25.76",
-      "resolved": "https://registry.npmjs.org/zod/-/zod-3.25.76.tgz",
-      "integrity": "sha512-gzUt/qt81nXsFGKIFcC3YnfEAx5NkunCfnDlvuBSSFS02bcXu4Lmea0AFIUwbLWxWPx3d9p8S5QoaujKcNQxcQ==",
+      "version": "4.0.5",
+      "resolved": "https://registry.npmjs.org/zod/-/zod-4.0.5.tgz",
+      "integrity": "sha512-/5UuuRPStvHXu7RS+gmvRf4NXrNxpSllGwDnCBcJZtQsKrviYXm54yDGV2KYNLT5kq0lHGcl7lqWJLgSaG+tgA==",
       "license": "MIT",
       "funding": {
         "url": "https://github.com/sponsors/colinhacks"
       }
-    },
-    "node_modules/zod-to-json-schema": {
-      "version": "3.24.6",
-      "resolved": "https://registry.npmjs.org/zod-to-json-schema/-/zod-to-json-schema-3.24.6.tgz",
-      "integrity": "sha512-h/z3PKvcTcTetyjl1fkj79MHNEjm+HpD6NXheWjzOekY7kV+lwDYnHw+ivHkijnCSMz1yJaWBD9vu/Fcmk+vEg==",
-      "license": "ISC",
-      "peerDependencies": {
-        "zod": "^3.24.1"
-      }
     }
   }
 }
diff --git a/package.json b/package.json
index 5973a804..6d017c4f 100644
--- a/package.json
+++ b/package.json
@@ -71,7 +71,7 @@
     "openapi-fetch": "^0.14.0",
     "simple-oauth2": "^5.1.0",
     "yargs-parser": "^22.0.0",
-    "zod": "^3.25.76"
+    "zod": "^4.0.5"
   },
   "engines": {
     "node": "^20.19.0 || ^22.12.0 || >= 23.0.0"