#!/usr/bin/env bash
# fake codex: emits thread.started, writes last message file, exits 0
out=""
prev=""
for a in "$@"; do [[ $prev == "-o" ]] && out=$a; prev=$a; done
echo '{"type":"thread.started","thread_id":"test-thread-123"}'
echo '{"type":"turn.completed"}'
echo "stub answer" > "$out"
exit 0