Yuntrack

MCP server (stdio transport) for tracking parcels via YunTrack.

How it works

The tracker calls services.yuntrack.com/Track/Query directly using a signed POST request (HMAC-SHA256, key found in the page bundle). Because Alibaba Cloud WAF blocks requests that lack Chrome's TLS fingerprint, a headless Chromium browser is kept alive in the background and all API calls are made via page.evaluate() — the browser's own fetch() — rather than loading the full tracking page each time. This keeps response times around 400 ms per query.

A shared browser context is reused across all calls so warm-up only happens once. The raw JSON from the API is returned as-is — no field interpretation.

Build

npm install
npx playwright install chromium
npm run build

Development & testing

npm run inspect   # opens MCP Inspector in the browser — lets you call tools interactively
npm run dev       # watch mode (tsc + node --watch)

---

Installing in Claude Desktop

1. Open (or create) ~/Library/Application Support/Claude/claude_desktop_config.json
2. Add the server under mcpServers:

{
  "mcpServers": {
    "yuntrack": {
      "command": "/absolute/path/to/mcp-yuntrack/node_modules/.bin/tsx",
      "args": ["/absolute/path/to/mcp-yuntrack/src/index.ts"]
    }
  }
}

3. Restart Claude Desktop — the track_parcel tool is now available.

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Installing in Claude Code (CLI)

Run once from any directory:

claude mcp add yuntrack /absolute/path/to/mcp-yuntrack/node_modules/.bin/tsx /absolute/path/to/mcp-yuntrack/src/index.ts

Restart Claude Code. The tool is available in every project.

To confirm it loaded:

claude mcp list

---

Installing in Claude Code via project config

Add a .claude/mcp.json (or mcp.json) in your project root:

{
  "mcpServers": {
    "yuntrack": {
      "command": "/absolute/path/to/mcp-yuntrack/node_modules/.bin/tsx",
      "args": ["/absolute/path/to/mcp-yuntrack/src/index.ts"]
    }
  }
}

This makes the server available to everyone who opens the project in Claude Code.

---

Tool: track_parcel

Single tracking number:

{ "trackingId": "UJ123456789SE" }

Batch (up to 100 IDs per call, sent in one request):

{ "trackingIds": ["UJ123456789SE", "BCM987654321SE"] }

Returns the raw JSON from the YunTrack Query API.