Description
_ensure_message_ids(messages) in agent_framework/_compaction.py fills each missing Message.message_id with f"msg_{index}", where index is the position in the list it receives. annotate_message_groups calls it indirectly via group_messages(messages[start_index:]) on a slice of the full list — so successive incremental calls collide with ids already assigned by earlier calls. The framework ends up with multiple distinct messages sharing the same message_id.
In the sample provided this was observed:
0: role=user id='msg_0'
1: role=assistant id='msg_1'
2: role=user id='msg_1'
3: role=assistant id='msg_2'
4: role=user id='msg_1'
5: role=assistant id='msg_2'
6: role=user id='msg_1'
7: role=assistant id='msg_2'
Downstream consumers assume message_id is unique. The most visible failure today is in SummarizationStrategy: _group_id_for derives group_id from message_id, so colliding ids collapse distinct groups into one.
Code Sample
import asyncio
import os
from agent_framework import (
Agent,
CompactionProvider,
InMemoryHistoryProvider,
SlidingWindowStrategy,
)
from agent_framework.openai import OpenAIChatCompletionClient
async def main() -> None:
agent = Agent(
client=OpenAIChatCompletionClient(
model="gpt-4o-mini", api_key=os.environ["OPENAI_API_KEY"]
),
name="Repro",
instructions="Reply in <= 4 words.",
context_providers=[
InMemoryHistoryProvider(),
CompactionProvider(
after_strategy=SlidingWindowStrategy(keep_last_groups=1000),
),
],
)
session = agent.create_session(session_id="repro")
for text in ["Say one.", "Say two.", "Say three.", "Say four."]:
await agent.run(text, session=session)
for i, m in enumerate(session.state["in_memory"]["messages"]):
print(f" {i}: role={m.role:9} id={m.message_id!r}")Error Messages / Stack Traces
Package Versions
agent-core-framework: 1.0.1
Python Version
Python 3.13
Additional Context
As a workaround I have been adding unique ids to messages outside of the agent loop
Description
_ensure_message_ids(messages)inagent_framework/_compaction.pyfills each missingMessage.message_idwithf"msg_{index}", whereindexis the position in the list it receives.annotate_message_groupscalls it indirectly viagroup_messages(messages[start_index:])on a slice of the full list — so successive incremental calls collide with ids already assigned by earlier calls. The framework ends up with multiple distinct messages sharing the samemessage_id.In the sample provided this was observed:
Downstream consumers assume
message_idis unique. The most visible failure today is inSummarizationStrategy:_group_id_forderivesgroup_idfrommessage_id, so colliding ids collapse distinct groups into one.Code Sample
import asyncio import os from agent_framework import ( Agent, CompactionProvider, InMemoryHistoryProvider, SlidingWindowStrategy, ) from agent_framework.openai import OpenAIChatCompletionClient async def main() -> None: agent = Agent( client=OpenAIChatCompletionClient( model="gpt-4o-mini", api_key=os.environ["OPENAI_API_KEY"] ), name="Repro", instructions="Reply in <= 4 words.", context_providers=[ InMemoryHistoryProvider(), CompactionProvider( after_strategy=SlidingWindowStrategy(keep_last_groups=1000), ), ], ) session = agent.create_session(session_id="repro") for text in ["Say one.", "Say two.", "Say three.", "Say four."]: await agent.run(text, session=session) for i, m in enumerate(session.state["in_memory"]["messages"]): print(f" {i}: role={m.role:9} id={m.message_id!r}")Error Messages / Stack Traces
Package Versions
agent-core-framework: 1.0.1
Python Version
Python 3.13
Additional Context
As a workaround I have been adding unique ids to messages outside of the agent loop