Python: fix(ag ui): allow text events when response_format is a json schema dictionary

python/packages/ag-ui/agent_framework_ag_ui/_agent_run.py

@@ -2956,14 +2956,18 @@ async def _run_agent_stream(
             snapshot_seed_messages,
             protected_tool_call_ids=protected_tool_call_ids,
         )
-    # Check for structured output mode (skip text content)
+    # Check for structured output mode (skip text content only for Pydantic models whose fields map to state/message)
     skip_text = False
-    response_format: type[Any] | None = None
+    response_format: Any | None = None
+    is_pydantic_response_format = False
     default_options = getattr(agent, "default_options", None)
     if isinstance(default_options, dict):
+        from pydantic import BaseModel
+
         typed_default_options = cast(dict[str, Any], default_options)
-        response_format = cast(type[Any] | None, typed_default_options.get("response_format"))
-        skip_text = response_format is not None
+        response_format = typed_default_options.get("response_format")
+        is_pydantic_response_format = isinstance(response_format, type) and issubclass(response_format, BaseModel)
+        skip_text = is_pydantic_response_format
 
     # Handle empty messages (emit RunStarted immediately since no agent response)
     if not messages and not only_cancelled_resume:
@@ -3578,8 +3582,8 @@ async def _run_agent_stream(
         from agent_framework import AgentResponse
         from pydantic import BaseModel
 
-        if not (isinstance(response_format, type) and issubclass(response_format, BaseModel)):
-            logger.warning("Skipping structured output parsing: response_format is not a Pydantic model type.")
+        if not is_pydantic_response_format:
+            logger.debug("Skipping structured output parsing: response_format is not a Pydantic model type.")
         else:
             logger.info(f"Processing structured output, update count: {len(all_updates)}")
             final_response = AgentResponse.from_updates(all_updates, output_format_type=response_format)

python/packages/ag-ui/tests/ag_ui/test_structured_output.py

@@ -261,3 +261,37 @@ async def stream_fn(
 
     # Should only have start and end events
     assert len(events) == 2  # RunStarted, RunFinished
+
+
+async def test_structured_output_with_json_schema_mapping_emits_text(
+    streaming_chat_client_stub, stream_from_updates_fixture
+):
+    """Test that JSON Schema mapping response_format still emits text content events."""
+    from agent_framework.ag_ui import AgentFrameworkAgent
+
+    json_payload = '{"name": "Alice", "age": 30}'
+    updates = [ChatResponseUpdate(contents=[Content.from_text(text=json_payload)])]
+
+    agent = Agent(
+        name="extractor",
+        instructions="Extract person info as JSON.",
+        client=streaming_chat_client_stub(stream_from_updates_fixture(updates)),
+    )
+    agent.default_options = {
+        "response_format": {
+            "type": "object",
+            "properties": {"name": {"type": "string"}, "age": {"type": "integer"}},
+            "required": ["name", "age"],
+        }
+    }
+
+    wrapper = AgentFrameworkAgent(agent=agent)
+    input_data = {"messages": [{"role": "user", "content": "Extract info for Alice aged 30"}]}
+
+    events: list[Any] = []
+    async for event in wrapper.run(input_data):
+        events.append(event)
+
+    text_events = [e for e in events if e.type == "TEXT_MESSAGE_CONTENT"]
+    assert len(text_events) > 0
+    assert text_events[0].delta == json_payload