Track YunExpress (YT…) parcels and automatically extract the UniUni (UUS…) last-mile tracking number.

YunExpress (YT + 16 digits) is one of the largest cross-border air linehaul networks from China to North America, frequently handing cleared US and Canadian parcels to UniUni (UUS…) for final doorstep delivery. When you query a YT… number on lastscanned, the top-level message field automatically surfaces the UniUni tracking number ('Handed to UniUni as UUS5BM1269395824723') so you can track both legs in two synchronous GET calls.

Barcode transition: YunExpress to UniUni

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

YunExpress lookup →Format & check-digit detector →
Origin / middle-mile carrier
YunExpress (yunexpress)
YunExpress Waybill
YT + 16 digits (/^YT\d{16}$/)
Origin example
YT2601500703194270
Final-mile carrier
UniUni (uniuni)
UniUni Last-Mile Barcode
UUS + 13–16 alphanumeric chars (/^UUS[0-9A-Z]{13,16}$/)
Final-mile example
UUS5BM1269395824723
Extracted in .message
Handed to UniUni as UUS5BM1269395824723

How the YunExpress → UniUni handoff works

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

1. Query the origin YT… waybill
Call GET /v1/track/YT2601500703194270. lastscanned auto-detects yunexpress in Pass 1 and returns all origin warehouse, export customs, and destination airport scans.
2. Read the secondary barcode from message
As soon as YunExpress assigns a domestic last-mile courier, lastscanned populates message: 'Handed to UniUni as UUS5BM1269395824723'.
3. Chain a synchronous GET on the UUS… barcode
Call GET /v1/track/UUS5BM1269395824723 to get UniUni's regional gateway scans, out_for_delivery driver dispatch, and delivered timestamp.
Origin auto-detection
/^YT\d{16}$/ routes to yunexpress in Pass 1.
Destination auto-detection
/^UUS[0-9A-Z]{13,16}$/ (Pass 1) and /^(UR\d{12,20}|U9999\d{6,20}|U000\d{6,20})$/ (Pass 2) route to uniuni.
Programmatic handoff regex
Match /^Handed to (.+?) as ([A-Z0-9-]+)$/i against pkg.message to chain the second lookup automatically.

Chain YunExpress → UniUni in code or MCP

Resolve both legs synchronously in TypeScript, curl, or your AI support agent via Streamable HTTP MCP.

Get an API keyWISMO agent guide

REST (Synchronous GET)

# 1. Query YunExpress origin waybill (extracts final-mile barcode in .message):
curl "https://api.lastscanned.com/v1/track/YT2601500703194270" \
  -H "Authorization: Bearer lsk_live_YOUR_API_KEY"

# 2. Query the extracted UniUni barcode:
curl "https://api.lastscanned.com/v1/track/UUS5BM1269395824723" \
  -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 to UniUni as UUS5BM1269395824723")
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 UniUni Last-Mile Handoff Tracking FAQ

How do I find the UniUni tracking number for a YunExpress (YT…) package?
Enter your 18-character YT… number into the lookup above or call GET /v1/track/YT... on lastscanned. The top-level message field in the JSON response returns 'Handed to UniUni as UUS...' as soon as the last-mile label is linked.
Can I track the UUS… UniUni number directly on lastscanned?
Yes. UniUni is a first-class carrier on lastscanned (carrier code: uniuni). Passing the UUS… number to GET /v1/track/:number returns live UniUni facility and driver delivery scans.
Does re-polling the YT… or UUS… number cost extra on the $4.99/mo Pro plan?
No. Pro includes 1,000 unique tracking numbers per month ($0.015 per extra unique number), and re-polling any tracking number you already queried during the billing period is free.

Other carrier handoff guides

Explore cross-border last-mile barcode extraction and domestic USPS consolidator overrides across all 31 carriers.

"USPS Currently Awaiting Package" 92… Checker →Tracking Number Format & Check-Digit Detector →

All 31 supported carriers

Major carriers

Regional and last mile

Cross-border