is webhook event source "url" property required or optional?

[m-ronchi]

from all the docs / examples, the only seemingly required properties are endpoint, port and method, e.g.:

spec:
  webhook:
    example:
      port: "12000"
      endpoint: /example1
      method: POST

but if I add the jsonschema to my vscode, it says that url is also required.

which is it? my webhooks already work without url (I am calling them internally in the cluster using the svc endpoint) and also I have no idea what to put there or what effect it should have