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"""
Example: Using Background Post-Hooks in AgentOS

This example demonstrates how to run post-hooks as FastAPI background tasks,
making them completely non-blocking.
"""

import asyncio

from agno.agent import Agent
from agno.db.sqlite import AsyncSqliteDb
from agno.hooks.decorator import hook
from agno.models.openai import OpenAIChat
from agno.os import AgentOS
from agno.run.agent import RunInput

# ---------------------------------------------------------------------------
# Create Example
# ---------------------------------------------------------------------------


@hook(run_in_background=True)
def log_request(run_input: RunInput, agent):
    """
    This pre-hook will run in the background before the agent processes the request.
    Note: Pre-hooks in background mode cannot modify run_input.
    """
    print(f"[Background Pre-Hook] Request received for agent: {agent.name}")
    print(f"[Background Pre-Hook] Input: {run_input.input_content}")


async def log_analytics(run_output, agent, session):
    """
    Post hook for logging analytics
    """
    print(f"[Post-Hook] Logging analytics for run: {run_output.run_id}")
    print(f"[Post-Hook] Agent: {agent.name}")
    print(f"[Post-Hook] Session: {session.session_id}")
    print("[Post-Hook] Analytics logged successfully!")


@hook(run_in_background=True)
async def send_notification(run_output, agent):
    """
    Post hook for sending notifications
    """
    print(f"[Post-Hook] Sending notification for agent: {agent.name}")
    await asyncio.sleep(3)
    print("[Post-Hook] Notification sent!")


# Create an agent with background post-hooks enabled
agent = Agent(
    id="background-task-agent",
    name="BackgroundTaskAgent",
    model=OpenAIChat(id="gpt-5.2"),
    instructions="You are a helpful assistant",
    db=AsyncSqliteDb(db_file="tmp/agent.db"),
    # Define hooks
    pre_hooks=[log_request],
    post_hooks=[log_analytics, send_notification],
    markdown=True,
)

# Create AgentOS
agent_os = AgentOS(
    agents=[agent],
)

# Get the FastAPI app
app = agent_os.get_app()


# When you make a request to POST /agents/{agent_id}/runs:
# 1. The agent will process the request
# 2. The response will be sent immediately to the user, with log_analytics executing with the normal execution flow
# 3. The pre-hooks (log_request) and post-hooks (send_notification) will run in the background without blocking the API response
# 4. The user doesn't have to wait for these tasks to complete

# Example request:
# curl -X POST http://localhost:8000/agents/background-task-agent/runs \
#   -F "message=Hello, how are you?" \
#   -F "stream=false"

# ---------------------------------------------------------------------------
# Run Example
# ---------------------------------------------------------------------------

if __name__ == "__main__":
    agent_os.serve(app="background_hooks_decorator:app", port=7777, reload=True)

​
Run the Example

# Clone and setup repo
git clone https://github.com/agno-agi/agno.git
cd agno/cookbook/05_agent_os/background_tasks

# Create and activate virtual environment
./scripts/demo_setup.sh
source .venvs/demo/bin/activate

python background_hooks_decorator.py