@Marvin, how do a I set tags on flow runs?

To set tags on flow runs in Prefect, you need to set them on the deployment level. Tags set on a deployment will be inherited by the deployment's flow runs. Here is what the Prefect documentation says:

Tags are a mechanism for grouping related work together across a diverse set of objects. Tags set on a deployment will be inherited by that deployment's flow runs. These tags can then be used to filter what runs are displayed on the primary UI dashboard, allowing you to customize different views into your work.

You can find more details on how to set tags for deployments in the Prefect documentation here: Deployments - Prefect Docs.