diff --git a/test/harness/package-lock.json b/test/harness/package-lock.json
index d1725f03..da803516 100644
--- a/test/harness/package-lock.json
+++ b/test/harness/package-lock.json
@@ -11,7 +11,7 @@
       "devDependencies": {
         "@github/copilot": "^0.0.403",
         "@types/node": "^25.2.0",
-        "openai": "^6.17.0",
+        "openai": "^6.21.0",
         "tsx": "^4.21.0",
         "typescript": "^5.9.3",
         "vitest": "^4.0.18",
@@ -1266,9 +1266,9 @@
       "license": "MIT"
     },
     "node_modules/openai": {
-      "version": "6.17.0",
-      "resolved": "https://registry.npmjs.org/openai/-/openai-6.17.0.tgz",
-      "integrity": "sha512-NHRpPEUPzAvFOAFs9+9pC6+HCw/iWsYsKCMPXH5Kw7BpMxqd8g/A07/1o7Gx2TWtCnzevVRyKMRFqyiHyAlqcA==",
+      "version": "6.21.0",
+      "resolved": "https://registry.npmjs.org/openai/-/openai-6.21.0.tgz",
+      "integrity": "sha512-26dQFi76dB8IiN/WKGQOV+yKKTTlRCxQjoi2WLt0kMcH8pvxVyvfdBDkld5GTl7W1qvBpwVOtFcsqktj3fBRpA==",
       "dev": true,
       "license": "Apache-2.0",
       "bin": {
diff --git a/test/harness/package.json b/test/harness/package.json
index 7a1a37ad..bf82baae 100644
--- a/test/harness/package.json
+++ b/test/harness/package.json
@@ -13,7 +13,7 @@
   "devDependencies": {
     "@github/copilot": "^0.0.403",
     "@types/node": "^25.2.0",
-    "openai": "^6.17.0",
+    "openai": "^6.21.0",
     "tsx": "^4.21.0",
     "typescript": "^5.9.3",
     "vitest": "^4.0.18",