I think this is a fine distinction to make, though it's worth noting that function arguments _can be_ colors as the author describes if the arguments have to come from a specific place, e.g. in languages where only `main` receives certain arguments relating to system functionality, or a capability framework where only the top-level function receives the capability token.

I don’t quite understand why the author says Context doesn’t count here. I’ve certainly experienced a top-down version where because a function starts accepting a Context, and therefore needs to be cancelable, lots of functions it calls now need to take a Context too, and check for cancellation. Perhaps the color here is cancelability, not the Context per se. (Which may be even worse, as a kind of “invisible color”.)