fix: V0.2 stability — token-limited orphan, message-filter order, rst…

python/packages/autogen-agentchat/src/autogen_agentchat/agents/_message_filter_agent.py

@@ -152,19 +152,17 @@ def produced_message_types(self) -> Sequence[type[BaseChatMessage]]:
         return self._wrapped_agent.produced_message_types
 
     def _apply_filter(self, messages: Sequence[BaseChatMessage]) -> Sequence[BaseChatMessage]:
-        result: List[BaseChatMessage] = []
-
+        # Preserve chronological order: collect indices per source_filter then emit in original order.
+        selected: set[int] = set()
         for source_filter in self._filter.per_source:
-            msgs = [m for m in messages if m.source == source_filter.source]
-
+            indexed = [(i, m) for i, m in enumerate(messages) if m.source == source_filter.source]
             if source_filter.position == "first" and source_filter.count:
-                msgs = msgs[: source_filter.count]
+                indexed = indexed[: source_filter.count]
             elif source_filter.position == "last" and source_filter.count:
-                msgs = msgs[-source_filter.count :]
-
-            result.extend(msgs)
-
-        return result
+                indexed = indexed[-source_filter.count :]
+            for i, _ in indexed:
+                selected.add(i)
+        return [m for i, m in enumerate(messages) if i in selected]
 
     async def on_messages(
         self,

python/packages/autogen-core/src/autogen_core/model_context/_token_limited_chat_completion_context.py

@@ -4,7 +4,8 @@
 from typing_extensions import Self
 
 from .._component_config import Component, ComponentModel
-from ..models import ChatCompletionClient, FunctionExecutionResultMessage, LLMMessage
+from .._types import FunctionCall
+from ..models import AssistantMessage, ChatCompletionClient, FunctionExecutionResultMessage, LLMMessage
 from ..tools import ToolSchema
 from ._chat_completion_context import ChatCompletionContext
 
@@ -70,10 +71,21 @@ async def get_messages(self) -> List[LLMMessage]:
                 middle_index = len(messages) // 2
                 messages.pop(middle_index)
                 token_count = self._model_client.count_tokens(messages, tools=self._tool_schema)
-        if messages and isinstance(messages[0], FunctionExecutionResultMessage):
-            # Handle the first message is a function call result message.
-            # Remove the first message from the list.
-            messages = messages[1:]
+        # Remove orphaned FunctionExecutionResultMessages whose call_id is no longer present.
+        # When a middle-list AssistantMessage carrying FunctionCalls is truncated, its paired
+        # FunctionExecutionResultMessage would otherwise be orphaned and cause API errors.
+        active_call_ids: set[str] = set()
+        for msg in messages:
+            if isinstance(msg, AssistantMessage) and isinstance(msg.content, list):
+                for item in msg.content:
+                    if isinstance(item, FunctionCall):
+                        active_call_ids.add(item.id)
+        messages = [
+            m
+            for m in messages
+            if not isinstance(m, FunctionExecutionResultMessage)
+            or (m.content and all(r.call_id in active_call_ids for r in m.content))
+        ]
         return messages
 
     def _to_config(self) -> TokenLimitedChatCompletionContextConfig:

python/packages/autogen-ext/src/autogen_ext/models/anthropic/_anthropic_client.py

@@ -542,11 +542,13 @@ def _rstrip_last_assistant_message(self, messages: Sequence[LLMMessage]) -> Sequ
         """
         Remove the last assistant message if it is empty.
         """
-        # When Claude models last message is AssistantMessage, It could not end with whitespace
+        if not messages:
+            return messages
         if isinstance(messages[-1], AssistantMessage):
             if isinstance(messages[-1].content, str):
                 messages[-1].content = messages[-1].content.rstrip()
-
+                if not messages[-1].content:
+                    return messages[:-1]
         return messages
 
     async def create(

python/packages/autogen-ext/src/autogen_ext/models/openai/_openai_client.py

@@ -491,11 +491,13 @@ def _rstrip_last_assistant_message(self, messages: Sequence[LLMMessage]) -> Sequ
         """
         Remove the last assistant message if it is empty.
         """
-        # When Claude models last message is AssistantMessage, It could not end with whitespace
+        if not messages:
+            return messages
         if isinstance(messages[-1], AssistantMessage):
             if isinstance(messages[-1].content, str):
                 messages[-1].content = messages[-1].content.rstrip()
-
+                if not messages[-1].content:
+                    return messages[:-1]
         return messages
 
     def _process_create_args(