Restrict write permissions only to specific attributes for custom API credentials

Hi,

I'm trying to create a custom integration (Integrations -> API credentials -> Add new credential) which, for the employee API, should only be able to update specific fields.
It seems like it's only possible to select specific attributes for "Read" (= "Readable employee attributes"), but not for "Write".
Is there a way to restrict write permissions only to specific attributes? If not, is there a specific reason, and will this be added in the future?

Thanks very much!
Thore