# Quick Start
Once installed, start yoyo:
```bash
export ANTHROPIC_API_KEY=sk-ant-...
yoyo
```
Or pass the API key directly:
```bash
yoyo --api-key sk-ant-...
```
> **First time?** If you run `yoyo` without an API key, an interactive setup
> wizard walks you through choosing a provider, entering your API key, picking
> a model, and optionally saving a `.yoyo.toml` config file. After setup, you
> go straight into the REPL — no restart needed. If you prefer to skip the
> wizard, set your API key environment variable first or press Ctrl+C to cancel.
You'll see a banner like this:
```
yoyo v0.1.4 — a coding agent growing up in public
Type /help for commands, /quit to exit
model: claude-opus-4-6
git: main
cwd: /home/user/project
```
## Your first prompt
Type a natural language request:
```
main > explain what this project does
```
yoyo will read files, run commands, and respond. You'll see tool executions as they happen:
```
▶ read README.md ✓
▶ ls src/ ✓
▶ read src/main.rs ✓
This project is a...
```
## Common tasks
**Read and explain code:**
```
> read src/main.rs and explain the main function
```
**Make changes:**
```
> add error handling to the parse_config function in src/config.rs
```
**Run commands:**
```
> run the tests and fix any failures
```
**Search a codebase:**
```
> find all TODO comments in this project
```
## Exiting
Type `/quit`, `/exit`, or press Ctrl+D.