How to build a crashproof customer service agent in

from swarm import Agent
from dbos import DBOS

def process_refund(context_variables, item_id, reason="NOT SPECIFIED"):
    """Refund an item. Refund an item. Make sure you have the item_id of the form item_... Ask for user confirmation before processing the refund."""
    user_name = context_variables.get("user_name", "user")
    print(f"[mock] Refunding for {user_name}, item {item_id}, because {reason}...")
    for i in range(1, 6):
        refund_step(i)
        DBOS.sleep(1)
    print("[mock] Refund successfully processed!")
    return "Success!"

@DBOS.step()
def refund_step(step_id):
    print(f"[mock] Processing refund step {step_id}... Press Control + C to quit")

@DBOS.step()
def apply_discount():
    """Apply a discount to the user's cart."""
    print("[mock] Applying discount...")
    return "Applied discount of 11%"

refunds_agent = Agent(
    name="Refunds Agent",
    instructions="Help the user with a refund. If the reason is that it was too expensive, offer the user a refund code. If they insist, then process the refund.",
    functions=[process_refund, apply_discount],
)

from dbos import DBOS, DBOSConfiguredInstance
from swarm import Swarm
from swarm.repl.repl import pretty_print_messages

DBOS()

@DBOS.dbos_class()
class DurableSwarm(Swarm, DBOSConfiguredInstance):
    def __init__(self, client=None):
        Swarm.__init__(self, client)
        DBOSConfiguredInstance.__init__(self, "openai_client")

    @DBOS.step()
    def get_chat_completion(self, *args, **kwargs):
        return super().get_chat_completion(*args, **kwargs)

    @DBOS.workflow()
    def run(self, *args, **kwargs):
        response = super().run(*args, **kwargs)
        pretty_print_messages(response.messages)
        return response

DBOS.launch()

from agents import refunds_agent

def main():
    client = DurableSwarm()
    print("Connecting to Durable Refund Agent 💪🐝")

    user_name = input("\033[90mWhat's your name\033[0m: \n")
    if user_name.strip() == "":
        return  # Exit if user doesn't provide a name

    query = "I want to refund item 99 because it's too expensive and I don't like its color! I want to proceed with the refund and also get a discount for my next purchase!"
    context_variables = {"user_name": user_name}

    client.run(
        agent=refunds_agent,
        messages=[{"role": "user", "content": query}],
        context_variables=context_variables,
    )

if __name__ == "__main__":
    main()

export OPENAI_API_KEY=<your_openai_key>

git clone https://github.com/dbos-inc/durable-swarm.git
cd examples/reliable_refund

python3 -m venv .venv
source .venv/bin/activate
pip install dbos git+https://github.com/openai/swarm.git

export PGPASSWORD=dbos
python3 start_postgres_docker.py

> python3 main.py

Connecting to Durable Refund Agent 💪🐝
What's your name:
Max
[mock] Refunding for Max, item item_99, because Too expensive and I don't like its color...
[mock] Processing refund step 1... Press Control + C to quit
[mock] Processing refund step 2... Press Control + C to quit
[mock] Processing refund step 3... Press Control + C to quit
^C⏎

# Resume from where the last completed step (step 3), continuing with step 4.
> python3 main.py

Connecting to Durable Refund Agent 💪🐝
[mock] Refunding for Max, item item_99, because Too expensive and I don't like its color...
[mock] Processing refund step 4... Press Control + C to quit
[mock] Processing refund step 5... Press Control + C to quit
[mock] Refund successfully processed!
[mock] Applying discount...
Refunds Agent:
process_refund("item_id"= "item_99", "reason"= "Too expensive and I don't like its color")
apply_discount()
Refunds Agent: I've processed the refund for item 99 and also applied a discount of 11% for your next purchase. If there's anything else you need, feel free to ask!