Add trackingToken to Device request object

This adds the optional trackingToken field to the Device request
object for explicit device linking via the Device Tracking Add-on.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: oschwald

CHANGELOG.md

@@ -1,6 +1,14 @@
 CHANGELOG
 =========
 
+8.4.0
+------------------
+
+* Added the input `/device/tracking_token`. This is the token generated by
+  the [Device Tracking Add-on](https://dev.maxmind.com/minfraud/track-devices)
+  for explicit device linking. You may provide this by providing
+  `trackingToken` to `Device`.
+
 8.3.0 (2026-01-20)
 ------------------
 

README.md

@@ -179,6 +179,7 @@ try {
   transaction = new minFraud.Transaction({
     device: new minFraud.Device({
       ipAddress: "81.2.69.160",
+      trackingToken: "abc123",
     }),
     event: new minFraud.Event({
       party: minFraud.Constants.EventParty.Customer,

src/request/device.spec.ts

@@ -27,4 +27,12 @@ describe('Device()', () => {
       });
     }).not.toThrow();
   });
+
+  it('sets trackingToken correctly', () => {
+    const device = new Device({
+      ipAddress: '1.1.1.1',
+      trackingToken: 'abc123',
+    });
+    expect(device.trackingToken).toBe('abc123');
+  });
 });

src/request/device.ts

@@ -26,6 +26,11 @@ interface DeviceProps {
    * identifies a visitor's session on the site.
    */
   sessionId?: string;
+  /**
+   * The tracking token from the Device Tracking Add-on for explicit device
+   * linking.
+   */
+  trackingToken?: string;
 }
 
 /**
@@ -42,6 +47,8 @@ export default class Device implements DeviceProps {
   public sessionAge?: number;
   /** @inheritDoc DeviceProps.sessionId */
   public sessionId?: string;
+  /** @inheritDoc DeviceProps.trackingToken */
+  public trackingToken?: string;
 
   public constructor(device: DeviceProps) {
     if (device.ipAddress != null && isIP(device.ipAddress) === 0) {