diff --git a/ai-hub/app/core/grpc/services/grpc_server.py b/ai-hub/app/core/grpc/services/grpc_server.py
index ccd4abc..0599063 100644
--- a/ai-hub/app/core/grpc/services/grpc_server.py
+++ b/ai-hub/app/core/grpc/services/grpc_server.py
@@ -80,8 +80,8 @@
         sandbox_cfg = shell_cfg.get("sandbox", {}) if isinstance(shell_cfg, dict) else {}
         if sandbox_cfg is None: sandbox_cfg = {}
         
-        # 1. Resolve Mode
-        mode_str = (sandbox_cfg.get("mode") or "STRICT").upper()
+        # 1. Resolve Mode (Default to PERMISSIVE to match UI expectation for unconfigured nodes)
+        mode_str = (sandbox_cfg.get("mode") or "PERMISSIVE").upper()
         grpc_mode = agent_pb2.SandboxPolicy.STRICT if mode_str == "STRICT" else agent_pb2.SandboxPolicy.PERMISSIVE
         
         # 2. Resolve Command Lists (fallback to some safe defaults if enabled but empty)