What it does XianyuAutoAgent is a Python bot that logs into China’s second-hand marketplace Xianyu and runs your storefront 24/7. It reads incoming messages, routes them to role-specific LLM “experts” (price haggler, tech support, generic customer service), and fires back replies with an optional fake typing delay so you look human.

The interesting bit The whole thing runs off your browser cookies and a single .env file. No official API, no OAuth dance — just F12, copy your cookies, paste them in, and the bot piggybacks on the web session. The “multi-expert” routing is really just prompt engineering: one LLM call classifies intent, then the request gets fed to a second prompt tuned for pricing, tech specs, or small talk.

Key highlights

• Cookie-based auth against Xianyu’s web interface (no API key from the platform itself)
• Four swappable prompt templates in prompts/ for intent classification, pricing, tech, and default replies
• “Staircase” price-drop strategy for automated bargaining
• Web search integration for technical product questions
• Manual override via a toggle keyword (default: typing a period switches to human mode)
• Defaults to Tongyi Qianwen, but any OpenAI-compatible endpoint works

Caveats

• The README warns the project may be “stopped or deleted at any time” due to its gray-area nature
• Several features listed as “planned” (sentiment analysis, market price comparison, RAG knowledge base, DingTalk alerts, web admin UI) are not yet implemented
• Relies on scraping web cookies, which will break if Xianyu changes its auth flow or detects automation

Verdict Worth a look if you’re already selling on Xianyu and want to experiment with LLM automation. Skip it if you need something stable, officially supported, or operating outside China’s second-hand ecosystem.