is there any way to restrict visibility of a specific field within a type? or do I have to create a separate type and add permissions there?

If you create a

READ

permission on that Type, and exclude that field from it, you can't query it, but it will still be visible in the schema though.

ah I see - I'm trying to do this in YAML, would you happen to know what it would look like?

Yes, you can specify fields on a permission in YAML like described here: https://docs-next.graph.cool/reference/project-configuration/graphcool.yml-foatho8aip#type:-permission

aah thanks, I missed that 🙂