Building a Mentoring Platform with 10 AI Agents: 6 Sessions, 1,289 Tool Calls

Six sessions. 1,289 tool calls. 84 files modified, 26 files created. That is how much tool usage went into a single Claude Code project. It all started with one sentence: "Have 10 agents build a master plan." TL;DR : Multi-agent is fast. But the more agents move, the less you do is a myth -- what actually happens is you have more to verify. QA works better as "find 5 at a time, repeat" than "find everything at once." Coffee Chat is a 1:1 AI mentoring platform connecting game industry professionals with mentees. The tech stack: Next.js 16, Supabase, Toss Payments, Resend. When I started, it was practically an empty shell. Dependencies were not installed, there was no .env.example , and the README was the default create-next-app template. Here is how Claude Code moved through it. 142 Tool Calls to Start: The Project Audit The first prompt in session 1: Do an initial project audit and make it runnable for local development. Tasks: 1) Detect the tech stack and how to run/build/test 2) Inst