stop_agent_exception.py
"""
Stop Agent Exception
=============================
Demonstrates stop agent exception.
"""
from agno.agent import Agent
from agno.db.sqlite import SqliteDb
from agno.exceptions import StopAgentRun
from agno.models.openai import OpenAIChat
from agno.run import RunContext
from agno.utils.log import logger
# ---------------------------------------------------------------------------
# Create Agent
# ---------------------------------------------------------------------------
def add_item(run_context: RunContext, item: str) -> str:
"""Add an item to the shopping list."""
if run_context.session_state is None:
run_context.session_state = {}
if "shopping_list" not in run_context.session_state:
run_context.session_state["shopping_list"] = []
run_context.session_state["shopping_list"].append(item)
len_shopping_list = len(run_context.session_state["shopping_list"])
if len_shopping_list < 3:
raise StopAgentRun(
f"Shopping list is: {run_context.session_state['shopping_list']}. We must stop the agent." # type: ignore
)
logger.info(
f"The shopping list is now: {run_context.session_state.get('shopping_list')}"
) # type: ignore
return f"The shopping list is now: {run_context.session_state.get('shopping_list')}" # type: ignore
agent = Agent(
model=OpenAIChat(id="gpt-5.2"),
session_id="stop_agent_exception_session",
db=SqliteDb(
session_table="stop_agent_exception_session",
db_file="tmp/stop_agent_exception.db",
),
# Initialize the session state with empty shopping list
session_state={"shopping_list": []},
tools=[add_item],
markdown=True,
)
# ---------------------------------------------------------------------------
# Run Agent
# ---------------------------------------------------------------------------
if __name__ == "__main__":
agent.print_response("Add milk", stream=True)
print(
f"Final session state: {agent.get_session_state(session_id='stop_agent_exception_session')}"
)
Run the Example
1
Set up your virtual environment
uv venv --python 3.12
source .venv/bin/activate
uv venv --python 3.12
.venv\Scripts\activate
2
Install dependencies
uv pip install -U agno openai sqlalchemy
3
Export your OpenAI API key
export OPENAI_API_KEY="your_openai_api_key_here"
$Env:OPENAI_API_KEY="your_openai_api_key_here"
4
Run the example
Save the code above as
stop_agent_exception.py, then run:python stop_agent_exception.py