diff --git a/src/app_controller.py b/src/app_controller.py
index 5153993..1689c4f 100644
--- a/src/app_controller.py
+++ b/src/app_controller.py
@@ -1496,21 +1496,22 @@ class AppController:
      })
 
   if kind in ("tool_result", "tool_call"):
-   role = "Tool" if kind == "tool_result" else "Vendor API"
-   content = ""
-   if kind == "tool_result":
-    content = payload.get("output", "")
-   else:
-    content = payload.get("script") or payload.get("args") or payload.get("message", "")
-    if isinstance(content, dict):
-     content = json.dumps(content, indent=1)
-   with self._pending_history_adds_lock:
-    self._pending_history_adds.append({
-      "role": role,
-      "content": f"[{kind.upper().replace('_', ' ')}]\n{content}",
-      "collapsed": True,
-      "ts": entry.get("ts", project_manager.now_ts())
-     })
+   if self.ui_auto_add_history:
+    role = "Tool" if kind == "tool_result" else "Vendor API"
+    content = ""
+    if kind == "tool_result":
+     content = payload.get("output", "")
+    else:
+     content = payload.get("script") or payload.get("args") or payload.get("message", "")
+     if isinstance(content, dict):
+      content = json.dumps(content, indent=1)
+    with self._pending_history_adds_lock:
+     self._pending_history_adds.append({
+       "role": role,
+       "content": f"[{kind.upper().replace('_', ' ')}]\n{content}",
+       "collapsed": True,
+       "ts": entry.get("ts", project_manager.now_ts())
+      })
   if kind == "history_add":
    payload = entry.get("payload", {})
    with self._pending_history_adds_lock: