Please read this first
Describe the bug
In certain scenarios, the Agents SDK returns the following error:
Example:
openai.NotFoundError: Error code: 404 - {'error': {'message': "Item with id 'rs_3c4caff36e34c099006900f0e3c66481909c15ac262a15b060' not found.", 'type': 'invalid_request_error', 'param': 'input', 'code': None}}
Configuration:
- Store is not set to
False
- Using default session management:
SQLiteSession
- All items stored in the database are sent back to the agent for each turn
- Multi-agent system architecture with handoffs:
- Agent 1:
gpt-5 with minimal reasoning (acts as the triage agent)
- Agent 2:
gpt-5 with medium reasoning
- Agent 3:
gpt-5 with low reasoning
Issue:
Agent 1 generates an empty reasoning item as shown below:
8|f00b2f3b-770b-4f40-9ca3-ae7700940a19_6555bacd-f286-42b3-9f25-e7a9ae94e3de|{"id":"rs_3c4caff36e34c099006900f0e3c66481909c15ac262a15b060","summary":[],"type":"reasoning"}|2025-10-28 16:36:16
After several steps (including outputs produced by Agent 2 and Agent 3), when Agent 1 regains control and any new message is passed, the error above is triggered.
Debug information
- Agents SDK version:
0.2.8
- Python version: Python 3.11.6
Repro steps
While the code that triggers this error in our system involves multiple agents and handoffs, the following simplified code reproduces the same error:
import asyncio
import random
from agents import (
Agent,
ItemHelpers,
Runner,
enable_verbose_stdout_logging,
function_tool,
)
enable_verbose_stdout_logging()
@function_tool
def how_many_jokes() -> int:
"""Return a random integer of jokes to tell between 1 and 10 (inclusive)."""
return random.randint(1, 10)
ORIGINAL_RS_ID = "rs_07a11282cddc7074006905172505c88198bd41b4889a8d5649"
def mangle_rs_id(original_rs_id: str) -> str:
return original_rs_id[:-2] + "ff"
async def main():
agent = Agent(
name="Joker",
instructions="Call the `how_many_jokes` tool once, and tell that many jokes.",
tools=[how_many_jokes],
model="gpt-5-nano",
)
rs_id = mangle_rs_id(ORIGINAL_RS_ID)
input_list = [
{"content": "We want to hear jokes", "role": "user"},
{
"id": rs_id,
"summary": [],
"type": "reasoning",
},
{
"arguments": "{}",
"call_id": "call_xkkWToQpzfvn0asJfDPo06Wj",
"name": "how_many_jokes",
"type": "function_call",
"id": "fc_07a11282cddc707400690517253a148198a2dad52c744c22ce",
"status": "completed",
},
{
"call_id": "call_xkkWToQpzfvn0asJfDPo06Wj",
"output": "7",
"type": "function_call_output",
},
]
result = Runner.run_streamed(
agent,
input=input_list,
)
async for event in result.stream_events():
if (
event.type == "run_item_stream_event"
and event.item.type == "message_output_item"
):
print(f"-- Message output:\n {ItemHelpers.text_message_output(event.item)}")
if __name__ == "__main__":
asyncio.run(main())
Expected behavior
The SDK should not error out, as we are not modifying or altering any reasoning items.
Please read this first
Describe the bug
In certain scenarios, the Agents SDK returns the following error:
Example:
Configuration:
FalseSQLiteSessiongpt-5with minimal reasoning (acts as the triage agent)gpt-5with medium reasoninggpt-5with low reasoningIssue:
Agent 1 generates an empty reasoning item as shown below:
After several steps (including outputs produced by Agent 2 and Agent 3), when Agent 1 regains control and any new message is passed, the error above is triggered.
Debug information
0.2.8Repro steps
While the code that triggers this error in our system involves multiple agents and handoffs, the following simplified code reproduces the same error:
Expected behavior
The SDK should not error out, as we are not modifying or altering any reasoning items.