> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/shlokjain2031/email-tracker-extension/llms.txt
> Use this file to discover all available pages before exploring further.

# TrackingPayload

> Data structure for encoding tracking information into tracking tokens

The `TrackingPayload` interface defines the data structure used to create tracking tokens. This payload is encoded into the tracking pixel URL and decoded when the pixel is accessed.

## Fields

<ParamField path="user_id" type="string" required>
  Unique identifier for the user or account that owns this tracking pixel. Used for data isolation and filtering.
</ParamField>

<ParamField path="email_id" type="string" required>
  Unique identifier for the specific email being tracked. This should be a unique value for each email sent.
</ParamField>

<ParamField path="recipient" type="string" required>
  Email address of the recipient. Used to associate open events with specific recipients.
</ParamField>

<ParamField path="sender_email" type="string">
  Email address of the sender. Optional field that can be used to identify which sender account was used.
</ParamField>

<ParamField path="sent_at" type="string" required>
  ISO 8601 timestamp indicating when the email was sent. Format: `YYYY-MM-DDTHH:mm:ss.sssZ`
</ParamField>

## Usage

This interface is used when:

* Creating tracking tokens with `encodeTrackingToken()` function
* Generating tracking pixel URLs for emails
* Decoding tracking tokens in the tracking endpoint

## Related APIs

* [Tracking pixel endpoint](/api/tracking-pixel) - Decodes `TrackingPayload` from tracking tokens
* [Mark suppress next](/api/suppression) - Uses `email_id` from the payload for suppression

## Example

```typescript theme={null}
const payload: TrackingPayload = {
  user_id: "user_123",
  email_id: "email_456",
  recipient: "recipient@example.com",
  sender_email: "sender@example.com",
  sent_at: "2024-01-15T10:30:00.000Z"
};

const token = encodeTrackingToken(payload);
const trackingUrl = `https://your-server.com/track/t/${token}.gif`;
```

## Database mapping

When a tracking pixel is accessed, the `TrackingPayload` data is stored in the `tracked_emails` table and used to create records in the `open_events` table.