Function pre_tool_use_answer 

pub fn pre_tool_use_answer(
    event: &str,
    verdict: PolicyVerdict<'_>,
) -> PolicyHookAnswer

A PreToolUse answer. Codex refuses a call with a deny decision and does not support ask from a hook, so an ask rule matched here says nothing and is left to the native rule, if any. No match prints nothing; input that cannot be read is denied.