Webhook filter for update fields

Hi there,

In the documentation of Webhooks Filters is mentioned that you can filter by field ID, but it is waitng an array of integers. As far as I know, I have used ids like (id) “field_2_string” when reading fields and “this_type_of_id” (index_name) for writing. There is also the uuid. But how can I get a numeric ID for fields that can be used in filters?

It says:

mutation {
    createWebhook(input: {
      actions: ["card.field_update"],
      name: "Field Update Webhook",
      pipe_id: 123456,
      url: "https://your-endpoint.com/",
      filters: {
        field_id: [ 123, 345 ]
      }
    }) {
      webhook {
        id
        actions
        url
      }
    }
  }

I try using the following mutation:

mutation {
  createWebhook(
    input: {
      actions: ["card.field_update"], 
      filters: { field_id: [ "field_37_string" ] },
      name: "card.field_update", 
      url: "myserver.app", 
      email: "myemail@gobusinessinc.com", 
      pipe_id: 1234
    }
  ) {
    webhook {
      id
      actions
      url
    }
  }
}

But the error is:

"Validation failed: Invalid format type for one or more filter values: [[\"field_37_string\"]]. The correct format is a non-null array of numeric ids: [ID], Invalid value(s) added to filter: [\"field_37_string\"]. Make sure the IDs belong to the resource where the webhook is being created"

What should I do?