How to Receive Custom Arguments in Event Webhook

[KentaYamada]

Hi, all.

I would like to set custom arguments in the request using the Node.js SDK and receive them in the Event Webhook, but I'm unable to receive them correctly. Could you please provide guidance on how to implement this?

Package versions

• node: 18.20
• @sendgrid/mail: 8.1.3

source code (typescript)

// Send email
const service = new MailService();
service.send({
   from: `Cafe de Gamoyon<${process.env.FROM}>`,
   to: payload.mail,
   bcc: bcc,
   subject: mailTemplate.subject,
   text: text,
  // is that correct ?
  customArgs: {
      mail_notification_id: mailNotificationId,
    },
});

// Define event webhook payload type
type SendgridEvent = {
  email: string;
  timestamp: Date;
  "smtp-id": string;
  event: string;
  sg_event_id: string;
  sg_message_id: string;
  category?: string | string[];
  response: string;
} & Partial<Record<string, string>>;

expected

{
  "email": "xxx",
  "timestamp": "xxx",
  "smtp-id":  "xxx",
  "event": "xxx",
  "sg_event_id": "xxx",
  "sg_message_id": "xxx",
  "category": "xxx",
  "response": "xxx",
  "mail_notification_id": "xxx"
}

actual

When I looked at the sample code, custom arguments were set in the personalizations. Is this the only way to receive them in the Event Webhook?
https://www.twilio.com/docs/sendgrid/for-developers/tracking-events/event#custom-arguments