curl --request GET \
  --url https://api.mudstack.com/workspaces/usage \
  --header 'Authorization: Bearer <token>' \
  --header 'x-account-id: <x-account-id>' \
  --header 'x-workspace-id: <x-workspace-id>'

{
  "members": 123,
  "storage": 123,
  "assets": 123
}