fix(end-node): normalize non-string plugin content

backend/openjiuwen_studio/core/manager/convertor/components/end.py

@@ -53,9 +53,14 @@ def end_convert(node: Node) -> dsl.Component:
                 response_template="",
             )
         else:
+            # A plugin node may emit a non-string payload (dict / list / number).
+            # Normalize it to a string so the End node's response_template stays
+            # serializable and the second dialogue round loads correctly (#1282).
+            raw_content = content.content
+            response_template = raw_content if isinstance(raw_content, str) else str(raw_content or "")
             configs = dsl.EndConfig(
                 stream_output=inputs.streaming,
-                response_template=content.content,
+                response_template=response_template,
             )
 
         end_node = dsl.Component(

backend/openjiuwen_studio/schemas/node.py

@@ -87,7 +87,10 @@ class LoopParam(BaseType):
 
 
 class Content(BaseType):
-    content: Optional[str] = Field("", alias="content")
+    # ``content`` may carry a non-string payload (dict / list / number) when a
+    # plugin node feeds the End node directly; consumers normalize it to a
+    # string, so keep the field permissive (#1282).
+    content: Optional[Any] = Field("", alias="content")
     streaming: Optional[bool] = Field(False, alias="streaming")
 
 

backend/tests/test_end_node_nonstring_content.py

@@ -0,0 +1,79 @@
+# -*- coding: utf-8 -*-
+# Copyright (c) Huawei Technologies Co., Ltd. 2026. All rights reserved.
+
+"""Unit tests for End node conversion with non-string content (issue #1282).
+
+A plugin node may emit a non-string payload (dict / list / number) into the
+End node's ``content``. ``end_convert`` must normalize it to a string so the
+``response_template`` stays serializable and the second dialogue round loads.
+"""
+
+import pytest
+
+from openjiuwen_studio.core.manager.convertor.components.end import end_convert
+from openjiuwen_studio.core.common.dsl import ComponentType
+from openjiuwen_studio.schemas.node import (
+    Content,
+    Inputs,
+    Meta,
+    Node,
+    NodeData,
+    NodePosition,
+)
+
+
+def _make_end_node(content_value) -> Node:
+    """Build an End node whose content carries the given payload."""
+    return Node(
+        id="end-1",
+        meta=Meta(position=NodePosition(x=0, y=0), node_id="end-1", name="End", type="end"),
+        data=NodeData(
+            title="End",
+            inputs=Inputs(
+                input_parameters={},
+                content=Content(content=content_value),
+                streaming=False,
+            ),
+        ),
+    )
+
+
+def test_end_convert_accepts_string_content():
+    node = _make_end_node("hello world")
+    component = end_convert(node)
+    assert component.type == ComponentType.COMPONENT_TYPE_END
+    assert component.configs["response_template"] == "hello world"
+
+
+def test_end_convert_normalizes_dict_content_to_string():
+    node = _make_end_node({"key": "value"})
+    component = end_convert(node)
+    assert component.type == ComponentType.COMPONENT_TYPE_END
+    template = component.configs["response_template"]
+    assert isinstance(template, str)
+    assert "key" in template
+
+
+def test_end_convert_normalizes_number_content_to_string():
+    node = _make_end_node(12345)
+    component = end_convert(node)
+    template = component.configs["response_template"]
+    assert isinstance(template, str)
+    assert template == "12345"
+
+
+def test_end_convert_handles_none_content_gracefully():
+    node = _make_end_node(None)
+    component = end_convert(node)
+    assert component.configs["response_template"] == ""
+
+
+def test_end_convert_keeps_serializable_configs_for_non_string_content():
+    # Regression guard: the dumped configs must be JSON-serializable even when
+    # the raw payload was a dict (the second dialogue round re-reads these).
+    import json
+
+    node = _make_end_node({"a": [1, 2, 3]})
+    component = end_convert(node)
+    json.dumps(component.configs)  # must not raise
+    assert isinstance(component.configs["response_template"], str)