Agent 101

A practical course on building AI agents — from core loop to multi-agent collaboration.

中文版

What is this?

Agent 101 is a hands-on course that teaches you how to build real AI agents using TypeScript and the Anthropic SDK. Each lesson introduces one new concept by modifying a minimal working agent — you can see exactly what changed and why.

The course ships with one app:

App	Description
apps/agent	TypeScript source files — run each lesson directly

Curriculum

Chapter 1 — Agent Core Loop & Tools

The foundation every agent is built on

Lesson	Title	Concept
1.1	Agent Core Loop	One while loop, one stop condition
1.2	Tools System	Dispatch map, four file tools
1.3	Steering	Inject instructions while the agent is running
1.4	Followup	Outer loop — continue after the agent finishes

Chapter 2 — Orchestration

Managing complex multi-step work

Lesson	Title	Concept
2.1	ToDo System	Self-updating checklist + Drift Guard
2.2	Sub-Agent Delegation	Spawn a fresh agent for focused sub-tasks
2.3	Skills System	Load expert knowledge on demand
2.4	JSON File-based Task System	Persistent tasks with dependency tracking

Chapter 3 — Context

Managing what the agent sees

Lesson	Title	Concept
3.1	Compaction	Run long tasks without hitting context limits
3.2	Context Engineering	What goes into the context window, and why it matters

Chapter 4 — Concurrency

Doing more than one thing at a time

Lesson	Title	Concept
4.1	Background Task Execution	Start a slow command and keep working

Chapter 5 — Collaboration

Agents working together

Lesson	Title	Concept
5.1	Agent Team System	Multiple agents, one shared filesystem
5.2	Team Protocol	Typed messages with request/response pairing
5.3	Autonomous Agents	Agents find and claim their own work
5.4	Worktree & Task Isolation	One git branch per task

Prerequisites

• Node.js 22+
• pnpm 9+
• An Anthropic API key

Getting Started

1. Clone and install

git clone https://github.com/yai-dev/a101.git
cd a101
pnpm install

2. Configure environment

cp .env.example .env
# Edit .env and add your ANTHROPIC_API_KEY

3. Run a lesson

cd apps/agent
npx tsx ch1-core/1.1-core-loop.ts

4. Start the course website

pnpm dev
# Opens at http://localhost:3000

Environment Variables

Variable	Required	Description
ANTHROPIC_API_KEY	Yes	Your Anthropic API key
MODEL_ID	No	Override the default model (default: claude-opus-4-5)
ANTHROPIC_BASE_URL	No	Override the API endpoint (useful for proxies)

Tech Stack

• Runtime: Node.js, TypeScript, tsx
• AI SDK: @anthropic-ai/sdk
• Package manager: pnpm workspaces

License

MIT © 2026 Yaid