diff --git a/apps/ai-game-creator-shell/src-tauri/src/agent/runtime_actions/tool_policy_snapshot.rs b/apps/ai-game-creator-shell/src-tauri/src/agent/runtime_actions/tool_policy_snapshot.rs
index 49e1a9da9..1c2fb8d7f 100644
--- a/apps/ai-game-creator-shell/src-tauri/src/agent/runtime_actions/tool_policy_snapshot.rs
+++ b/apps/ai-game-creator-shell/src-tauri/src/agent/runtime_actions/tool_policy_snapshot.rs
@@ -179,6 +179,16 @@ pub(in crate::agent) fn agent_runtime_tool_policy_snapshot_at(
             auto_tools.push(tool.to_string());
         }
     }
+    if isolated {
+        // Keep the isolated-child contract explicit even when a denied tool
+        // is unavailable on the current platform and therefore absent from
+        // the executable catalog (for example, the Windows-only Cocos bridge).
+        for tool in ISOLATED_AGENT_UNSCOPED_DENIED_TOOLS {
+            if !denied_tools.iter().any(|candidate| candidate == tool) {
+                denied_tools.push((*tool).to_string());
+            }
+        }
+    }
     Ok(AgentRuntimeToolPolicySnapshot {
         run_profile: default_agent_runtime_run_profile(),
         run_profile_binding_fingerprint: String::new(),