Update space

app.py

@@ -144,8 +144,7 @@ def build_messages(history: list[dict], message: str, briefing: str | None, turn
         msgs.append({
             "role": "system",
             # Use concatenation to avoid any accidental multiline f-string issues
-            "content": "Pre-game briefing (user-provided):
-" + briefing[:4000]
+            "content": "Pre-game briefing (user-provided):\n" + (briefing[:4000] if isinstance(briefing, str) else "")
         })
 
     for m in history or []: