Python: fix(core): include tool trajectory details in summarizer input

python/packages/core/agent_framework/_compaction.py

@@ -1198,12 +1198,72 @@ def _tool_result_text(value: Any) -> str:
         if text_parts:
             return "\n".join(text_parts)
     if isinstance(value, Mapping):
-        return json.dumps(cast(Mapping[str, object], value), ensure_ascii=False)
+        try:
+            return json.dumps(cast(Mapping[str, object], value), ensure_ascii=False, default=str)
+        except (TypeError, ValueError):
+            return str(cast(object, value))
     return str(cast(object, value))
 
 
+def _format_summary_content(content: Content) -> str:
+    """Render one content item for the summarizer input transcript.
+
+    Tool calls and results are rendered with their name, arguments, result
+    text, and call id so the summarizer sees the tool trajectory instead of a
+    bare content type. Text contents are aggregated via ``Message.text``
+    instead. Returns an empty string when the item has no structured rendering
+    of its own, so callers can fall back to the legacy rendering.
+    """
+    if content.type == "function_call":
+        arguments = _tool_result_text(content.arguments) if content.arguments is not None else ""
+        call = f"function_call {content.name or ''}({arguments})"
+        if content.call_id:
+            call += f" [call_id={content.call_id}]"
+        return call
+    if content.type == "function_result":
+        result_text = _tool_result_text(content.result) if content.result is not None else "no result"
+        if content.exception:
+            result_text = f"error({content.exception}): {result_text}"
+        call_id_suffix = f" [call_id={content.call_id}]" if content.call_id else ""
+        return f"function_result: {result_text}{call_id_suffix}"
+    if content.type == "mcp_server_tool_call":
+        arguments = _tool_result_text(content.arguments) if content.arguments is not None else ""
+        call = f"mcp_tool_call {content.tool_name or ''}({arguments})"
+        if content.call_id:
+            call += f" [call_id={content.call_id}]"
+        return call
+    if content.type == "mcp_server_tool_result":
+        result_text = _tool_result_text(content.output)
+        if content.exception:
+            result_text = f"error({content.exception}): {result_text}"
+        call_id_suffix = f" [call_id={content.call_id}]" if content.call_id else ""
+        return f"mcp_tool_result: {result_text}{call_id_suffix}"
+    if content.type in ("function_approval_request", "function_approval_response"):
+        nested_call = content.function_call
+        name = "" if nested_call is None else nested_call.name or nested_call.tool_name or ""
+        label = "approval_request" if content.type == "function_approval_request" else "approval_response"
+        rendered = f"{label}: {name} [id={content.id}]"
+        if content.type == "function_approval_response":
+            rendered += f" approved={content.approved}"
+        return rendered
+    return ""
+
+
 def _format_summary_message(index: int, message: Message) -> str:
-    content_text = message.text
+    parts: list[str] = []
+    pending_text: list[str] = []
+    for content in message.contents:
+        rendered = _format_summary_content(content)
+        if rendered:
+            if pending_text:
+                parts.append(" ".join(pending_text))
+                pending_text = []
+            parts.append(rendered)
+        elif content.type == "text" and content.text:
+            pending_text.append(content.text)
+    if pending_text:
+        parts.append(" ".join(pending_text))
+    content_text = "; ".join(parts)
     if not content_text:
         content_text = ", ".join(content.type for content in message.contents)
     return f"{index}. [{message.role}] {content_text}"

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

@@ -3,6 +3,7 @@
 from __future__ import annotations
 
 import logging
+from datetime import date
 from typing import Any
 
 import pytest
@@ -36,6 +37,7 @@
     included_token_count,
 )
 from agent_framework._compaction import (
+    _format_summary_message,
     _select_summary_input_groups,
     _serialize_message,
     append_compaction_message,
@@ -972,6 +974,184 @@ def test_summary_input_selection_does_not_retokenize_selected_transcript() -> No
     )
 
 
+def test_format_summary_message_includes_function_call_details() -> None:
+    message = Message(
+        role="assistant",
+        contents=[Content.from_function_call(call_id="call_1", name="get_weather", arguments='{"city":"Seattle"}')],
+    )
+
+    rendered = _format_summary_message(1, message)
+
+    assert "get_weather" in rendered
+    assert '{"city":"Seattle"}' in rendered
+    assert "[call_id=call_1]" in rendered
+
+
+def test_format_summary_message_includes_function_result_and_exception() -> None:
+    message = Message(
+        role="tool",
+        contents=[Content.from_function_result(call_id="call_1", result="42", exception="ValueError")],
+    )
+
+    rendered = _format_summary_message(2, message)
+
+    assert "function_result" in rendered
+    assert "42" in rendered
+    assert "error(ValueError)" in rendered
+    assert "[call_id=call_1]" in rendered
+
+
+def test_format_summary_message_renders_function_result_without_call_id() -> None:
+    message = Message(
+        role="tool",
+        contents=[Content("function_result", call_id=None, result="done")],
+    )
+
+    rendered = _format_summary_message(3, message)
+
+    assert "done" in rendered
+    assert "call_id" not in rendered
+
+
+def test_format_summary_message_combines_tool_calls_with_text() -> None:
+    message = Message(
+        role="assistant",
+        contents=[
+            "I'll check the weather.",
+            Content.from_function_call(call_id="call_1", name="get_weather", arguments='{"city":"Seattle"}'),
+        ],
+    )
+
+    rendered = _format_summary_message(4, message)
+
+    assert "I'll check the weather." in rendered
+    assert "get_weather" in rendered
+
+
+def test_format_summary_message_preserves_text_only_messages() -> None:
+    message = Message(role="user", contents=["hello world"])
+
+    rendered = _format_summary_message(5, message)
+
+    assert rendered == "5. [user] hello world"
+
+
+def test_format_summary_message_includes_mcp_tool_details() -> None:
+    message = Message(
+        role="assistant",
+        contents=[
+            Content.from_mcp_server_tool_call(
+                call_id="mcp_1",
+                tool_name="search",
+                server_name="test_server",
+                arguments='{"query":"x"}',
+            ),
+            Content.from_mcp_server_tool_result(
+                call_id="mcp_1",
+                output=[Content.from_text("found")],
+            ),
+        ],
+    )
+
+    rendered = _format_summary_message(6, message)
+
+    assert "search" in rendered
+    assert '{"query":"x"}' in rendered
+    assert "[call_id=mcp_1]" in rendered
+    assert "found" in rendered
+
+
+def test_format_summary_message_includes_approval_request() -> None:
+    message = Message(
+        role="assistant",
+        contents=[
+            Content.from_function_approval_request(
+                id="approval_1",
+                function_call=Content.from_function_call(
+                    call_id="call_1", name="send_email", arguments='{"to":"a@b.c"}'
+                ),
+            )
+        ],
+    )
+
+    rendered = _format_summary_message(7, message)
+
+    assert "approval_request" in rendered
+    assert "send_email" in rendered
+    assert "[id=approval_1]" in rendered
+
+
+def test_format_summary_message_includes_approval_response() -> None:
+    message = Message(
+        role="assistant",
+        contents=[
+            Content.from_function_approval_response(
+                approved=True,
+                id="approval_1",
+                function_call=Content.from_function_call(
+                    call_id="call_1", name="send_email", arguments='{"to":"a@b.c"}'
+                ),
+            )
+        ],
+    )
+
+    rendered = _format_summary_message(8, message)
+
+    assert "approval_response" in rendered
+    assert "approved=True" in rendered
+
+
+def test_format_summary_message_stringifies_non_json_mcp_result_without_crash() -> None:
+    message = Message(
+        role="tool",
+        contents=[Content("mcp_server_tool_result", call_id="mcp_1", output={"when": date(2026, 1, 1)})],
+    )
+
+    rendered = _format_summary_message(9, message)
+
+    assert "2026" in rendered
+    assert "[call_id=mcp_1]" in rendered
+
+
+def test_format_summary_message_preserves_time_order_for_mixed_contents() -> None:
+    message = Message(
+        role="assistant",
+        contents=[
+            "I'll check the weather.",
+            Content.from_function_call(call_id="call_1", name="get_weather", arguments='{"city":"Seattle"}'),
+            "Please wait.",
+        ],
+    )
+
+    rendered = _format_summary_message(10, message)
+
+    assert rendered.index("I'll check the weather.") < rendered.index("function_call")
+    assert rendered.index("function_call") < rendered.index("Please wait.")
+
+
+def test_format_summary_message_uses_tool_name_for_mcp_approval() -> None:
+    message = Message(
+        role="assistant",
+        contents=[
+            Content.from_function_approval_request(
+                id="approval_mcp_1",
+                function_call=Content.from_mcp_server_tool_call(
+                    call_id="mcp_1",
+                    tool_name="search",
+                    server_name="test_server",
+                    arguments='{"query":"x"}',
+                ),
+            )
+        ],
+    )
+
+    rendered = _format_summary_message(11, message)
+
+    assert "approval_request" in rendered
+    assert "search" in rendered
+    assert "[id=approval_mcp_1]" in rendered
+
+
 async def test_summarization_strategy_returns_false_when_summary_generation_fails(
     caplog: Any,
 ) -> None: