Lesson 1. What is HAPI and Why You Need It#
Why This Matters#
Imagine: you’re working with an AI assistant (say, Claude Code) on your computer. It writes code, edits files, runs commands. But you need to step away — grab coffee, head to a meeting, take a walk. Without HAPI, your AI agent stops and waits for you at the computer. With HAPI, you pull out your phone and continue working right from it — without losing progress.
HAPI is a tool that lets you control AI agents remotely: from your phone, tablet, or any browser.
What is an AI Agent?#
An AI agent is a program with artificial intelligence that can perform tasks on your computer. For example:
- Claude Code (by Anthropic) — writes and edits code
- Codex (by OpenAI) — also helps with code
- Gemini CLI (by Google) — another AI assistant
- OpenCode — an open-source alternative
They all work in the terminal (command line) of your computer. HAPI doesn’t replace them — it “wraps” them, adding the ability to control them remotely.
The Key Feature: Seamless Handoff#
Seamless Handoff is the ability to switch between your computer and phone without losing context.
How it works:
- You’re working with an AI agent in the terminal on your computer
- You send a message from your phone — control automatically transfers to the phone
- The terminal shows “Remote mode — waiting for input”
- You return to the computer, press double space — and you’re back to local control
No restarts, no data loss. The same session, the same state.
How HAPI Differs from Happy#
HAPI is inspired by the Happy project, but is fundamentally different:
| Happy | HAPI | |
|---|---|---|
| Where data is stored | On a cloud server (encrypted) | On your computer |
| Architecture | Centralized — one server for everyone | Decentralized — everyone runs their own hub |
| What the server does | Stores your encrypted data | Relay only forwards traffic, stores nothing |
| Installation | Multiple services (database, cache, server) | One command |
In simple terms:
- Happy is like Gmail: your emails sit on Google’s servers (encrypted, but still there).
- HAPI is like running your own mail server: everything is on your machine, and the “postman” (relay) only delivers envelopes without looking inside.
What are Hub and Relay?#
- Hub is the “control center” running on your computer. It stores sessions, manages connections, and provides the web interface.
- Relay is an intermediary server that simply forwards encrypted traffic between your phone and computer. It cannot read your data — it’s encrypted using WireGuard + TLS (military-grade encryption technologies).
What HAPI Can Do#
- 📱 Control from your phone — send commands to your AI agent from anywhere
- ✅ Approve requests — AI wants to edit a file? Approve with one tap from your phone
- 🔄 Seamless switching — computer ↔ phone without losing progress
- 🤖 Any AI of your choice — Claude Code, Codex, Gemini, OpenCode
- 🖥️ Terminal anywhere — run commands right from your phone
- 🎤 Voice control — talk to your AI agent by voice
- 🔒 Security — data never leaves your computer
Lesson Summary#
- HAPI is a tool for remotely controlling AI agents from your phone and browser
- The key feature is Seamless Handoff: switching between devices without losing context
- Unlike Happy, HAPI is decentralized: data stays on your computer
- Relay only forwards encrypted traffic — it cannot see your data
- HAPI supports Claude Code, Codex, Gemini, and OpenCode
In the next lesson, we’ll install HAPI on your computer.