Access parent(obj) in graphql resolver defined as controller action

This comes from strapi slack channel where I initially asked it.

I am writing my custom GraphQL resolvers and trying to follow the guide here: GraphQL - Strapi Developer Documentation

I put the code of my resolver into my controller and my schema.graphql.js points to my controller method as a resolver.
Alternatively I could write the actual resolver right in the schema.graphql.js as the document shows, but I wanted to have a checkbox in Admin UI for permissions control that appears if I have a controller action.

I saw that the signature of a controller action takes only one argument, e.g. async blah(ctx) while in my resolver I need to access the parent object (known in strapi world as the obj). The documentation says that I can get it via ctx.params and the options via ctx.query.

The obj parameter is available via ctx.params and the options are available via ctx.query in the controller’s action.

Unfortunately, that is not true.
Both the ctx.params and ctx.query contain the options in slightly different form.
I tried to inspect the ctx object to see if I can find where the obj is, but I could not find it.

Can someone tell me where on Earth can I get the obj if I define my resolver as a controller action?

And perhaps I should file a ticket for documentation update to be factually correct?