diff --git a/.github/workflows/runner-full-stack-e2e.yml b/.github/workflows/runner-full-stack-e2e.yml
index 1be9745ab35..79294323a5a 100644
--- a/.github/workflows/runner-full-stack-e2e.yml
+++ b/.github/workflows/runner-full-stack-e2e.yml
@@ -440,7 +440,7 @@ jobs:
                       "model": "gpt-5.6-sol",
                       "permissionMode": "approve-all",
                       "permissionModePinned": True,
-                      "systemInstructions": "",
+                      "systemInstructions": "Descriptor launch probe.",
                       "runtimeContext": None,
                       "tools": [],
                   },