diff --git a/src/app/endpoints/responses.py b/src/app/endpoints/responses.py
index 8dff2b596..0ebacd5dd 100644
--- a/src/app/endpoints/responses.py
+++ b/src/app/endpoints/responses.py
@@ -859,7 +859,7 @@ async def shield_violation_generator(
         api_params: ResponsesApiParams
         context: ResponsesContext
     Yields:
-        SSE-formatted strings for streaming events, ending with [DONE]
+        SSE-formatted strings for streaming events
     """
     normalized_conv_id = normalize_conversation_id(api_params.conversation)
     available_quotas = get_available_quotas(
@@ -935,8 +935,6 @@ async def shield_violation_generator(
     data_json = json.dumps(completed_event)
     yield f"event: response.completed\ndata: {data_json}\n\n"
 
-    yield "data: [DONE]\n\n"
-
 
 def _sanitize_response_dict(
     response_dict: dict[str, Any],
@@ -1249,8 +1247,6 @@ async def response_generator(
             latest_response_object.output,
         )
 
-    yield "data: [DONE]\n\n"
-
 
 async def generate_response(
     generator: AsyncIterator[str],
@@ -1301,6 +1297,8 @@ async def generate_response(
             turn_summary.llm_response,
         )
         _finalize_responses_root_span(root_span, turn_summary)
+        # Persist conversation state before clients can close the stream.
+        yield "data: [DONE]\n\n"
     finally:
         root_span.end()
 
diff --git a/tests/unit/app/endpoints/test_responses.py b/tests/unit/app/endpoints/test_responses.py
index 38dc06d49..87aac2b2e 100644
--- a/tests/unit/app/endpoints/test_responses.py
+++ b/tests/unit/app/endpoints/test_responses.py
@@ -1228,7 +1228,7 @@ async def test_handle_streaming_blocked_returns_sse_consumes_shield_generator(
         assert "event: response.output_item.added" in body
         assert "event: response.output_item.done" in body
         assert "event: response.completed" in body
-        assert "[DONE]" in body
+        assert body.count("data: [DONE]") == 1
         mock_client.responses.create.assert_not_called()
 
     @pytest.mark.asyncio