diff --git a/api/core/callback_handler/workflow_tool_callback_handler.py b/api/core/callback_handler/workflow_tool_callback_handler.py
index 23aabd99708..8c48a62d93f 100644
--- a/api/core/callback_handler/workflow_tool_callback_handler.py
+++ b/api/core/callback_handler/workflow_tool_callback_handler.py
@@ -1,6 +1,7 @@
 from collections.abc import Generator, Iterable, Mapping
 from typing import Any
 
+from configs import dify_config
 from core.callback_handler.agent_tool_callback_handler import DifyAgentCallbackHandler, print_text
 from core.ops.ops_trace_manager import TraceQueueManager
 from core.tools.entities.tool_entities import ToolInvokeMessage
@@ -19,8 +20,9 @@ class DifyWorkflowCallbackHandler(DifyAgentCallbackHandler):
         trace_manager: TraceQueueManager | None = None,
     ) -> Generator[ToolInvokeMessage, None, None]:
         for tool_output in tool_outputs:
-            print_text("\n[on_tool_execution]\n", color=self.color)
-            print_text("Tool: " + tool_name + "\n", color=self.color)
-            print_text("Outputs: " + tool_output.model_dump_json()[:1000] + "\n", color=self.color)
-            print_text("\n")
+            if dify_config.DEBUG:
+                print_text("\n[on_tool_execution]\n", color=self.color)
+                print_text("Tool: " + tool_name + "\n", color=self.color)
+                print_text("Outputs: " + tool_output.model_dump_json()[:1000] + "\n", color=self.color)
+                print_text("\n")
             yield tool_output
diff --git a/api/tests/unit_tests/core/callback_handler/test_workflow_tool_callback_handler.py b/api/tests/unit_tests/core/callback_handler/test_workflow_tool_callback_handler.py
index 5b53c5965ce..81ac48b2036 100644
--- a/api/tests/unit_tests/core/callback_handler/test_workflow_tool_callback_handler.py
+++ b/api/tests/unit_tests/core/callback_handler/test_workflow_tool_callback_handler.py
@@ -32,8 +32,16 @@ def mock_print_text(mocker: MockerFixture):
     return mocker.patch("core.callback_handler.workflow_tool_callback_handler.print_text")
 
 
+@pytest.fixture
+def enable_debug(mocker: MockerFixture):
+    """Force DEBUG on so the handler emits its verbose stdout traces."""
+    mocker.patch("core.callback_handler.workflow_tool_callback_handler.dify_config.DEBUG", True)
+
+
 class TestDifyWorkflowCallbackHandler:
-    def test_on_tool_execution_single_output_success(self, handler: DifyWorkflowCallbackHandler, mock_print_text):
+    def test_on_tool_execution_single_output_success(
+        self, handler: DifyWorkflowCallbackHandler, mock_print_text, enable_debug
+    ):
         # Arrange
         tool_name = "test_tool"
         tool_inputs = {"a": 1}
@@ -63,7 +71,9 @@ class TestDifyWorkflowCallbackHandler:
             ]
         )
 
-    def test_on_tool_execution_multiple_outputs(self, handler: DifyWorkflowCallbackHandler, mock_print_text):
+    def test_on_tool_execution_multiple_outputs(
+        self, handler: DifyWorkflowCallbackHandler, mock_print_text, enable_debug
+    ):
         # Arrange
         tool_name = "multi_tool"
         outputs = [
@@ -101,6 +111,29 @@ class TestDifyWorkflowCallbackHandler:
         assert results == []
         mock_print_text.assert_not_called()
 
+    def test_on_tool_execution_skips_print_when_debug_disabled(
+        self, handler: DifyWorkflowCallbackHandler, mock_print_text, mocker: MockerFixture
+    ):
+        """When DEBUG is off, outputs are still yielded but nothing is printed
+        and model_dump_json() is never invoked."""
+        # Arrange
+        mocker.patch("core.callback_handler.workflow_tool_callback_handler.dify_config.DEBUG", False)
+        message = MagicMock()
+
+        # Act
+        results = list(
+            handler.on_tool_execution(
+                tool_name="quiet_tool",
+                tool_inputs={},
+                tool_outputs=[message],
+            )
+        )
+
+        # Assert
+        assert results == [message]
+        mock_print_text.assert_not_called()
+        message.model_dump_json.assert_not_called()
+
     @pytest.mark.parametrize(
         ("invalid_outputs", "expected_exception"),
         [
@@ -110,7 +143,7 @@ class TestDifyWorkflowCallbackHandler:
         ],
     )
     def test_on_tool_execution_invalid_outputs_type(
-        self, handler: DifyWorkflowCallbackHandler, invalid_outputs, expected_exception
+        self, handler: DifyWorkflowCallbackHandler, invalid_outputs, expected_exception, enable_debug
     ):
         # Arrange
         tool_name = "invalid_tool"
@@ -125,7 +158,9 @@ class TestDifyWorkflowCallbackHandler:
                 )
             )
 
-    def test_on_tool_execution_long_json_truncation(self, handler: DifyWorkflowCallbackHandler, mock_print_text):
+    def test_on_tool_execution_long_json_truncation(
+        self, handler: DifyWorkflowCallbackHandler, mock_print_text, enable_debug
+    ):
         # Arrange
         tool_name = "long_json_tool"
         long_json = "x" * 1500
@@ -147,7 +182,9 @@ class TestDifyWorkflowCallbackHandler:
             color="blue",
         )
 
-    def test_on_tool_execution_model_dump_json_exception(self, handler: DifyWorkflowCallbackHandler, mock_print_text):
+    def test_on_tool_execution_model_dump_json_exception(
+        self, handler: DifyWorkflowCallbackHandler, mock_print_text, enable_debug
+    ):
         # Arrange
         tool_name = "exception_tool"
         bad_message = MagicMock()
@@ -167,7 +204,7 @@ class TestDifyWorkflowCallbackHandler:
         assert mock_print_text.call_count >= 2
 
     def test_on_tool_execution_none_message_id_and_trace_manager(
-        self, handler: DifyWorkflowCallbackHandler, mock_print_text
+        self, handler: DifyWorkflowCallbackHandler, mock_print_text, enable_debug
     ):
         # Arrange
         tool_name = "optional_params_tool"