For example, let's say I have the following code
const foo = "this is foo";
I would like to click on foo and press a key to annotate a type
const foo: string = "this is foo";
Visual studio code already knows the type, because is there when you hover over it. How would I make a key bind?
You can auto-add types by hovering over the variable and clicking Quick fix → infer parameter types from usage. The keyboard shortcut for this is ⌘ + ., then ↵.
VSCode already displaying the correct type out of the box means that typescript is inferring it for you. Adding the same declaration again would just add to the word count.