Add a page directly under the workspace using Notion API

Question

I'm currently trying to implement adding pages using Notion's API.

I have confirmed that a new page can be added by specifying the ID of the page or database (table), but is it not possible to add a page to the workspace?

I thought it would work if I passed it in the form below, but an error is returned...

{
 "parent": {
 "type": "workspace",
 "workspace": true
 }
}

"message": "body failed validation. Fix one:\nbody.parent.page_id should be defined, instead was `undefined`.\nbody.parent.database_id should be defined, instead was `undefined`.",

Can someone please help me?