Attribute Macro instrument 

#[instrument]

Drop-in replacement for #[tracing::instrument] that defaults to skip_all, making field logging opt-in.

Pass fields(name = expr) to record specific values. All other tracing::instrument options (name, level, target, ret, err, parent, follows_from) flow through unchanged.

User-supplied skip(...) or skip_all are rejected at compile time: skip_all is already enforced and fields(...) is the way to opt back in.