curl --request GET \
  --url https://{cluster}.cognitedata.com/api/v1/projects/{project}/models/statistics/spaces \
  --header 'Authorization: Bearer <token>'

{
  "items": [
    {
      "space": "<string>",
      "containers": 123,
      "views": 123,
      "dataModels": 123,
      "edges": 123,
      "softDeletedEdges": 123,
      "nodes": 123,
      "softDeletedNodes": 123
    }
  ]
}