discord の webhook で mention したい

const user_id = '502486808211357707';
const mention_string = `<@!${user_id}>`;

export const sendDiscordMessage = async (
  message: string,
  discordWebhookUrl: DiscordWebhookUrl,
) => {
  // send message to Discord webhook
  await axios.post(discordWebhookUrl.url, {
    content:
      message +
      '\n' +
      mention_string +
      '\n' +
      '@tkt' +
      '\n' +
      '@tkt#6539'
    allowed_mentions: {
      parse: ['users'],
    },
  });
};