Function summarize_input_for_log 

pub(crate) fn summarize_input_for_log(input: &[APIInputMessage]) -> String

Logs the shape and order of a request’s input items when Azure rejects it.

Azure’s item-shape errors (e.g. an out-of-place reasoning item whose encrypted_content “could not be verified”) name an item by id but not by position, so diagnosing one from the error alone means guessing at what the request actually looked like. This spells out every item’s type, id, and response_id in order, which is what identifies a reasoning item sitting next to the wrong call.