Python: Fix Foundry reasoning MCP compaction

python/packages/core/agent_framework/_compaction.py

@@ -74,16 +74,16 @@ def _has_content_type(message: Message, content_type: str) -> bool:
     return any(content.type == content_type for content in message.contents)
 
 
-def _has_function_call(message: Message) -> bool:
-    return _has_content_type(message, "function_call")
+def _has_tool_call(message: Message) -> bool:
+    return any(content.type in {"function_call", "mcp_server_tool_call"} for content in message.contents)
 
 
 def _has_reasoning(message: Message) -> bool:
     return _has_content_type(message, "text_reasoning")
 
 
 def _is_tool_call_assistant(message: Message) -> bool:
-    return message.role == "assistant" and _has_function_call(message)
+    return message.role == "assistant" and _has_tool_call(message)
 
 
 def _is_reasoning_only_assistant(message: Message) -> bool:

python/packages/core/tests/core/test_compaction.py

@@ -45,6 +45,20 @@ def _assistant_function_call(call_id: str) -> Message:
     )
 
 
+def _assistant_mcp_call(call_id: str) -> Message:
+    return Message(
+        role="assistant",
+        contents=[
+            Content.from_mcp_server_tool_call(
+                call_id=call_id,
+                tool_name="search",
+                server_name="test_server",
+                arguments='{"query":"x"}',
+            )
+        ],
+    )
+
+
 def _assistant_reasoning_and_function_calls(*call_ids: str) -> Message:
     contents: list[Content] = [Content.from_text_reasoning(text="thinking")]
     for call_id in call_ids:
@@ -154,6 +168,23 @@ def test_group_annotations_handle_same_message_reasoning_and_function_calls() ->
     assert _group_has_reasoning(messages[1]) is True
 
 
+async def test_sliding_window_keeps_reasoning_and_mcp_call_atomic() -> None:
+    messages = [
+        Message(role="system", contents=["system"]),
+        Message(role="assistant", contents=[Content.from_text_reasoning(id="rs_1", text="thinking")]),
+        _assistant_mcp_call("mcp_1"),
+        Message(role="assistant", contents=["answer"]),
+        Message(role="user", contents=["follow up"]),
+    ]
+    annotate_message_groups(messages)
+
+    await SlidingWindowStrategy(keep_last_groups=3)(messages)
+
+    assert messages[1].additional_properties[EXCLUDED_KEY] is False
+    assert messages[2].additional_properties[EXCLUDED_KEY] is False
+    assert _group_id(messages[1]) == _group_id(messages[2])
+
+
 def test_annotate_message_groups_with_tokenizer_adds_token_counts() -> None:
     messages = [
         Message(role="user", contents=["hello"]),

python/packages/foundry_hosting/agent_framework_foundry_hosting/_responses.py

@@ -1110,7 +1110,7 @@ async def _item_to_message(item: Item, *, approval_storage: ApprovalStorage | No
         reason_contents: list[Content] = []
         if reasoning.summary:
             for summary in reasoning.summary:
-                reason_contents.append(Content.from_text(summary.text))
+                reason_contents.append(Content.from_text_reasoning(id=reasoning.id, text=summary.text))
         return Message(role="assistant", contents=reason_contents)
 
     if item.type == "mcp_call":
@@ -1383,7 +1383,7 @@ async def _output_item_to_message(item: OutputItem, *, approval_storage: Approva
         contents: list[Content] = []
         if reasoning.summary:
             for summary in reasoning.summary:
-                contents.append(Content.from_text(summary.text))
+                contents.append(Content.from_text_reasoning(id=reasoning.id, text=summary.text))
         return Message(role="assistant", contents=contents)
 
     if item.type == "mcp_call":

python/packages/foundry_hosting/tests/test_responses.py

@@ -813,6 +813,8 @@ async def test_reasoning(self) -> None:
         msg = await _output_item_to_message(item)
         assert msg.role == "assistant"
         assert len(msg.contents) == 1
+        assert msg.contents[0].type == "text_reasoning"
+        assert msg.contents[0].id == "r-1"
         assert msg.contents[0].text == "thinking hard"
 
     async def test_reasoning_no_summary(self) -> None:
@@ -1298,6 +1300,8 @@ async def test_reasoning_with_summary(self) -> None:
         assert msg is not None
         assert msg.role == "assistant"
         assert len(msg.contents) == 1
+        assert msg.contents[0].type == "text_reasoning"
+        assert msg.contents[0].id == "r-1"
         assert msg.contents[0].text == "thinking hard"
 
     async def test_reasoning_no_summary(self) -> None: