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Hi guys,
Can anyone give me a piece of advice on how to run a flow from python without manually inserting the flow_id?

Hi <@U01C4F9T88P> where are you wanting to run your flow? If it's just on your local machine you could simply use flow.run()

I have tried all options but it is not clear to me how to make that automatically

Without knowing your exact use case it's a bit hard to advise but as background, you need a flow ID so that your agent knows which flow it is running.  If you just want to check your flow locally, you can use flow.run() (as I mentioned above).  If you want a flow to run in Cloud after you register it, you could use client.create_flow_run and use the flow id that is returned when you register a flow.

As a simple example:

```from prefect import Flow, task
from prefect.client.client import Client

@task()
def hello():
    print('hello')

with Flow(name='simple-flow') as flow:
    hello()    

# flow.run()
id = flow.register('PROJECT_NAME')
client = Client()
client.create_flow_run(flow_id=id)```

However, this is assuming I have an agent running, right?

Yes - you'll always need an agent running to run flows in Cloud.

How does the agent know, it should run this flow?

The agent will poll the api to see if there are flow runs waiting to be run.  You can customize which agent runs which flow run using labels - there's more about it in the agents section of the docs:

<https://docs.prefect.io/orchestration/agents/overview.html>

Hey <@ULXMV9SD7>

What are the best ways to utilise an agent? I.e. will I need to have it polling on a VM or?

What are the other deployment methods to host the polling agent?

Hi <@U01AKLVKQMP> - You can use a local agent or Docker, Kubernetes or Fargate - <https://docs.prefect.io/orchestration/agents/overview.html|the agents section in the docs> have more info to answer those questions.

My question is doesn't the agent have to be consistently turned on?

I.e. it has to be running as a background process listening for tasks from the cloud api?

Because for example Fargate is ephemeral, so I wondered about that?

Yep - technically they are querying the API for task runs and flow runs and you'll need them on whenever you want to run a flow run from the API.  Fargate Agents aren't generally installed to run on Fargate itself - they can be spun up anywhere with the correct variables set.

Cool thanks <@ULXMV9SD7> I'll have a review :slightly_smiling_face:

And another question, coming back to your example <@ULXMV9SD7>

```from prefect import Flow, task
from prefect.client.client import Client

@task()
def hello():
    print('hello')

with Flow(name='simple-flow') as flow:
    hello()    

# flow.run()
id = flow.register('PROJECT_NAME')
client = Client()
client.create_flow_run(flow_id=id)```
Imagine that I register the flow in a script different from the one I execute the client, how could I then know the id flow? Is there here any best practice?

Hi <@U01C4F9T88P> - if you need to you can query for a flow id using the client/ API: <https://docs.prefect.io/orchestration/concepts/api.html#authenticating-the-client-with-cloud>