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>A data field called "imageURL" that's a string -- is that a remote or local URL? Where did it come from/how much can I trust that it's well-formed?

Put that information in your types and (i) you don't need to write those comments and (ii) the compiler can help you check if you haven't made mistakes.

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I said "why isn't this a `URL` instead of a string". I know we should "Put that information in your types". The code is written. I can't safely make that change until I know the invariants, and if the person who wrote the code had written a doc comment, I would know them.

> The code is [already] written[ and doesn't include that information in its types].

By that logic, the code is already written and doesn't include that information in its comments, either.

> if the person who wrote the code had written a doc comment, I would know [the invariants].

If you're going to ask that the person who wrote the code have written it differently, there's (in general, at least) no reason to ask for comments in preference to types.

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