This is pretty much exactly what an oauth2 flow is. You generate a single-use-specific token and constrain it with the limited permissions you choose. If a site

This is pretty much exactly what an oauth2 flow is. You generate a single-use-specific token and constrain it with the limited permissions you choose. If a site wants to offer an oauth token flow where users can put a time or credit usage limit on the token they absolutely can do so.