Background Execution
Start a background agent run that returns PENDING immediately, then poll for completion or cancel it.
Example demonstrating background execution with polling and cancellation.
"""
Example demonstrating background execution with polling and cancellation.
Background execution allows you to start an agent run that returns immediately
with a PENDING status, while the actual work continues in the background.
You can then poll for completion or cancel the run.
Requirements:
- PostgreSQL running (./cookbook/scripts/run_pgvector.sh)
- OPENAI_API_KEY set
Usage:
.venvs/demo/bin/python cookbook/02_agents/14_advanced/background_execution.py
"""
import asyncio
from agno.agent import Agent
from agno.db.postgres import PostgresDb
from agno.models.openai import OpenAIResponses
from agno.run.base import RunStatus
# ---------------------------------------------------------------------------
# Config
# ---------------------------------------------------------------------------
db = PostgresDb(
db_url="postgresql+psycopg://ai:ai@localhost:5532/ai",
session_table="background_exec_sessions",
)
# ---------------------------------------------------------------------------
# Create and Run Background Examples
# ---------------------------------------------------------------------------
async def example_background_run_with_polling():
"""Start a background run and poll until complete."""
print("=" * 60)
print("Example 1: Background run with polling")
print("=" * 60)
agent = Agent(
name="BackgroundAgent",
model=OpenAIResponses(id="gpt-5-mini"),
description="An agent that runs in the background",
db=db,
)
# Start a background run — returns immediately with PENDING status
run_output = await agent.arun(
"What is the capital of France? Answer in one sentence.",
background=True,
)
print(f"Run ID: {run_output.run_id}")
print(f"Session ID: {run_output.session_id}")
print(f"Status: {run_output.status}")
assert run_output.status == RunStatus.pending, (
f"Expected PENDING, got {run_output.status}"
)
# Poll for completion
print("\nPolling for completion...")
for i in range(30):
await asyncio.sleep(1)
result = await agent.aget_run_output(
run_id=run_output.run_id,
session_id=run_output.session_id,
)
if result is None:
print(f" [{i + 1}s] Run not found in DB yet")
continue
print(f" [{i + 1}s] Status: {result.status}")
if result.status == RunStatus.completed:
print(f"\nCompleted! Content: {result.content}")
break
elif result.status == RunStatus.error:
print(f"\nFailed! Content: {result.content}")
break
else:
print("\nTimed out waiting for completion")
print()
async def example_cancel_background_run():
"""Start a background run and cancel it before completion."""
print("=" * 60)
print("Example 2: Cancel a background run")
print("=" * 60)
agent = Agent(
name="CancellableAgent",
model=OpenAIResponses(id="gpt-5-mini"),
description="An agent whose run can be cancelled",
db=db,
)
# Start a long background run
run_output = await agent.arun(
"Write a very detailed essay about the history of computing. "
"Make it at least 5000 words with sections and subsections.",
background=True,
)
print(f"Run ID: {run_output.run_id}")
print(f"Status: {run_output.status}")
# Wait a moment for the run to start
await asyncio.sleep(2)
# Cancel the run
print("Cancelling run...")
cancelled = await agent.acancel_run(run_id=run_output.run_id)
print(f"Cancel result: {cancelled}")
# Check the final state
await asyncio.sleep(1)
result = await agent.aget_run_output(
run_id=run_output.run_id,
session_id=run_output.session_id,
)
if result:
print(f"Final status: {result.status}")
print()
async def example_cancel_before_start():
"""Cancel a run before it even starts (cancel-before-start semantics)."""
print("=" * 60)
print("Example 3: Cancel-before-start")
print("=" * 60)
from agno.run.cancel import cancel_run
agent = Agent(
name="PreCancelAgent",
model=OpenAIResponses(id="gpt-5-mini"),
description="An agent whose run is cancelled before starting",
db=db,
)
# Pre-generate a run ID
from uuid import uuid4
run_id = str(uuid4())
# Cancel the run BEFORE it starts
print(f"Pre-cancelling run {run_id}...")
cancel_run(run_id)
# Now start the run with that ID — it should detect the cancellation
run_output = await agent.arun(
"This should be cancelled before it runs.",
background=True,
run_id=run_id,
)
print(f"Run ID: {run_output.run_id}")
print(f"Initial status: {run_output.status}")
# Wait and check — the background task should detect the cancellation
await asyncio.sleep(2)
result = await agent.aget_run_output(
run_id=run_output.run_id,
session_id=run_output.session_id,
)
if result:
print(f"Final status: {result.status}")
print()
async def main():
await example_background_run_with_polling()
await example_cancel_background_run()
await example_cancel_before_start()
print("All examples completed!")
if __name__ == "__main__":
asyncio.run(main())Background task lifetime
background=True detaches the run from its consumer while the event loop remains alive. These standalone scripts use asyncio.run: when the main coroutine exits, unfinished tasks are cancelled, including after a polling timeout. Keep the loop alive until the desired terminal state, or explicitly cancel and observe the run before leaving. A saved pending row alone does not restart execution.
A running AgentOS server can keep work alive after client disconnects. For recovery across process restarts, configure its durable queue.
Run the Example
Set up your virtual environment
uv venv --python 3.12
source .venv/bin/activateInstall dependencies
uv pip install -U agno "psycopg[binary]" openai sqlalchemyExport your OpenAI API key
export OPENAI_API_KEY="your_openai_api_key_here"Run PgVector
docker run -d \
-e POSTGRES_DB=ai \
-e POSTGRES_USER=ai \
-e POSTGRES_PASSWORD=ai \
-e PGDATA=/var/lib/postgresql \
-v pgvolume:/var/lib/postgresql \
-p 5532:5432 \
--name pgvector \
agnohq/pgvector:18Run the example
Save the code above as background_execution.py, then run:
python background_execution.pyFull source: cookbook/02_agents/14_advanced/background_execution.py