I’m sorry to say it’s just a very ugly cURL script! It looks like this:

url="$(echo $note | sed -e 's|content|https://www.joelotter.com|' -e 's|\.md|/|')"

echo "Waiting for URL to become available..."
until $(curl --output /dev/null --silent --head --fail $url); do
  printf '.'
  sleep 5
done
echo "Page is up."