Summary
Creator Magic’s Mike walks through building “Silicon Seeker,” an autonomous AI shopping agent that searches eBay for Mac Mini M4 listings and prepares checkout links — all without manual browsing. The project is built on three open-source layers: OpenClaw as the agent runtime, GStack (a Claude Code framework quietly released by Y Combinator CEO Garry Tan), and the Zapier SDK as the action layer that connects the agent to eBay’s Browse API.
The video covers the full setup from scratch: installing GStack inside Claude Code, using its “office hours” mode to scope the project with an engineering-review loop before writing any code, and connecting a Zapier account to eBay’s marketplace. A notable detail is GStack’s ability to hand off architecture decisions to a second AI (Codex or Gemini) for an independent review before committing to a build path — a lightweight multi-agent check built into the framework.
Because eBay’s native API is seller-focused, Mike shows how to build a custom Zapier SDK integration from scratch to handle buyer-side actions like listing search and deep-link checkout generation. The video doubles as a practical introduction to GStack, which had received little YouTube coverage at the time of filming. Viewers come away with a working blueprint for building commerce-capable AI agents using Claude Code as the backbone.
📺 Source: Creator Magic · Published June 24, 2026
🏷️ Format: Hands On Build
