Track Yanwen (…YP / YW…) cross-border parcels handed off to UniUni (UUS…) for North American delivery.

Yanwen frequently routes US and Canadian e-commerce parcels to UniUni (UUS…) for final-mile delivery after customs clearance. Calling GET /v1/track/:number on lastscanned returns the Yanwen international timeline and populates the top-level message field with 'Handed to UniUni as UUS...' so your app or agent can chain the local UniUni lookup automatically.

Barcode transition: Yanwen to UniUni

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

Yanwen lookup →Format & check-digit detector →
Origin / middle-mile carrier
Yanwen (yanwen)
Yanwen S10 / Commercial Waybill
2 letters + 9 digits + YP or YW + 3 letters + 12 digits
Origin example
YWBZX260123456789
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 Yanwen → UniUni handoff works

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

1. Query the Yanwen waybill
Send GET /v1/track/YWBZX... to retrieve origin facility induction, export flight departure, and port arrival scans.
2. Read the UniUni barcode from message
lastscanned extracts the exchange barcode and formats message as 'Handed to UniUni as UUS...'.
3. Query UniUni for doorstep delivery
Send GET /v1/track/UUS... to get UniUni local warehouse arrival, driver out_for_delivery status, and proof-of-delivery completion timestamps.
Origin carrier code
yanwen (auto-detected from …YP with S10 check digit or YW + 3 letters + 12 digits).
Destination carrier code
uniuni (auto-detected from UUS…, UR…, U9999…, or U000…).
Coverage across US & Canada
Tracks both US and Canadian UniUni regional delivery hubs in one schema.

Chain Yanwen → 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 Yanwen origin waybill (extracts final-mile barcode in .message):
curl "https://api.lastscanned.com/v1/track/YWBZX260123456789" \
  -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"

Yanwen to UniUni Last-Mile Handoff Tracking FAQ

How do I know if my Yanwen package was handed to UniUni or USPS?
Query your Yanwen tracking number on lastscanned. The top-level message field names both the destination carrier and the new tracking number (e.g. 'Handed to UniUni as UUS...' or 'Handed to USPS as 92...').
Does lastscanned support non-UUS UniUni partner numbers like UR… or U9999…?
Yes. UniUni's Pass 2 detector matches UR + 12–20 digits, U9999 + 6–20 digits, and U000 + 6–20 digits automatically, and any GV…/JY… partner number can be tracked with ?carrier=uniuni.

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