Track YunExpress parcels through customs clearance and OnTrac final-mile delivery.

YunExpress consolidates cross-border e-commerce parcels under an origin waybill (YT2621200705470145) and injects them into OnTrac (1LS729108273411) via LAX / EWR / ORD customs release to OnTrac facility. Querying lastscanned with ?carrier=yunexpress returns origin export and linehaul events, while querying the OnTrac tracking number returns domestic final-mile delivery scans.

Try a live tracking number:

Barcode transition: YunExpress to OnTrac

When YunExpress clears customs and hands off to OnTrac, lastscanned surfaces the secondary tracking number in the top-level message field.

Origin / middle-mile carrier
YunExpress (yunexpress)
YunExpress Waybill
YT + 16 digits
Origin example
YT2621200705470145
Final-mile carrier
OnTrac (ontrac)
OnTrac Barcode
1LS… or C/D + 14 digits
Final-mile example
1LS729108273411
Extracted in .message
Handed over to final-mile carrier OnTrac (1LS729108273411) — LAX / EWR / ORD customs release to OnTrac facility

How the YunExpress → OnTrac handoff works

Follow the parcel across both networks without waiting on asynchronous webhooks or losing visibility at the handoff boundary.

1. Origin induction (YunExpress)
The merchant inducts the parcel into YunExpress under origin tracking ID YT2621200705470145.
2. Linehaul & customs (LAX / EWR / ORD customs release to OnTrac facility)
The shipment clears customs at LAX / EWR / ORD customs release to OnTrac facility and receives domestic OnTrac barcode 1LS729108273411.
3. Final-mile delivery (OnTrac)
OnTrac completes local regional sortation and doorstep delivery with photo confirmation.
Origin Carrier Slug
yunexpress
Destination Carrier Slug
ontrac
Primary Injection Gateway
LAX / EWR / ORD customs release to OnTrac facility

Chain YunExpress → OnTrac in code or MCP

Resolve both legs synchronously in TypeScript, curl, or your AI support agent via Streamable HTTP MCP. Want automatic alerts when this handoff updates? Add the tracking number in Dashboard Watches, or use the Free API (5/day), Pro ($4.99/mo for 1,000 numbers), or an Instant 25-Pack ($0.50).

REST (Synchronous GET)

# 1. Query YunExpress origin waybill (extracts final-mile barcode in .message):
curl "https://api.lastscanned.com/v1/track/YT2621200705470145" \
  -H "Authorization: Bearer lsk_live_YOUR_API_KEY"

# 2. Query the extracted OnTrac barcode:
curl "https://api.lastscanned.com/v1/track/1LS729108273411" \
  -H "Authorization: Bearer lsk_live_YOUR_API_KEY"

TypeScript (Automatic Handoff Chaining)

const headers = { Authorization: `Bearer ${process.env.LASTSCANNED_API_KEY}` };
const originRes = await fetch(`https://api.lastscanned.com/v1/track/${encodeURIComponent(number)}`, { headers });
const originPkg = await originRes.json();

// Extract secondary barcode from top-level message ("Handed over to final-mile carrier OnTrac (1LS729108273411) — LAX / EWR / ORD customs release to OnTrac facility")
const handoff = originPkg.message?.match(/^Handed to (.+?) as ([A-Z0-9-]+)$/i);
if (handoff) {
  const [, , lastMileNumber] = handoff;
  const destRes = await fetch(`https://api.lastscanned.com/v1/track/${encodeURIComponent(lastMileNumber)}`, { headers });
  const destPkg = await destRes.json();
}

Remote MCP (Claude Code / Cursor / ChatGPT)

claude mcp add --transport http lastscanned https://mcp.lastscanned.com \
  --header "Authorization: Bearer lsk_live_YOUR_API_KEY"

YunExpress to OnTrac Handoff Tracking FAQ

How do I track a YunExpress parcel handed off to OnTrac?
Query GET /v1/track/YT2621200705470145?carrier=yunexpress for origin and customs milestones, and GET /v1/track/1LS729108273411?carrier=ontrac for OnTrac final-mile delivery scans.
Can I get automatic alerts when YunExpress hands off to OnTrac?
Yes. Add YT2621200705470145 or 1LS729108273411 in lastscanned Dashboard Watches at https://app.lastscanned.com/watches or subscribe via webhook.

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