diff --git a/src/api/sse_routes.py b/src/api/sse_routes.py
index 7a00101..75486ef 100644
--- a/src/api/sse_routes.py
+++ b/src/api/sse_routes.py
@@ -12,6 +12,6 @@ router = APIRouter(prefix="/api/events", tags=["sse"])
 async def event_stream(request: Request):
     """SSE 端点（占位，F17 实现真实推送）"""
     async def generate():
-        yield f"data: {{"}}\"type\":\"connected\"}}\n\n"
+        yield 'data: {"type":"connected"}\n\n'
 
     return StreamingResponse(generate(), media_type="text/event-stream")