# Interactive Mode (REPL)
Interactive mode is the default when you run yoyo in a terminal. It gives you a read-eval-print loop where you can have a multi-turn conversation with the agent.
## Starting
```bash
yoyo
# or
cargo run
```
## The prompt
The prompt shows your current git branch (if you're in a git repo):
```
main 🐙 › _
```
If you're not in a git repo, you get a plain prompt:
```
🐙 › _
```
## Line editing & history
yoyo uses [rustyline](https://crates.io/crates/rustyline) for a full readline experience:
- **Arrow keys**: Navigate within the current line (← →) and through command history (↑ ↓)
- **Inline hints**: As you type a slash command, a dimmed suggestion appears after the cursor showing the completion and a short description — e.g. typing `/he` shows `lp — Show help for commands`. Press Tab or → to accept.
- **Tab completion**: Type `/` and press Tab to see available slash commands with descriptions — each command is shown alongside a short summary of what it does. Partial matches work too — `/he<Tab>` suggests `/help` and `/health`. After typing a command + space, argument-aware completions kick in:
- `/model <Tab>` — suggests known model names (Claude, GPT, Gemini, etc.)
- `/provider <Tab>` — suggests known provider names (anthropic, openai, google, etc.)
- `/think <Tab>` — suggests thinking levels (off, minimal, low, medium, high)
- `/git <Tab>` — suggests git subcommands (status, log, add, diff, branch, stash)
- `/pr <Tab>` — suggests PR subcommands (list, view, diff, comment, create, checkout)
- `/save <Tab>` and `/load <Tab>` — suggest `.json` session files in the current directory
- File paths also complete — type `src/ma<Tab>` to get `src/main.rs`, or `Cargo<Tab>` to get `Cargo.toml`. Directories complete with a trailing `/` for easy continued navigation.
- **History recall**: Previous inputs are saved across sessions
- **Keyboard shortcuts**: Ctrl-A (start of line), Ctrl-E (end of line), Ctrl-K (kill to end), Ctrl-W (delete word back)
- **History file**: Stored at `$XDG_DATA_HOME/yoyo/history` (defaults to `~/.local/share/yoyo/history`)
## How it works
1. You type a message
2. yoyo sends it to the LLM along with conversation history
3. The LLM may call tools (read files, run commands, etc.)
4. Tool results are streamed back — you see each tool as it executes
5. The final text response is printed
6. Token usage and cost are shown after each turn
## Tool output
When yoyo uses tools, you'll see status indicators:
```
▶ $ cargo test ✓ (2.1s)
▶ read src/main.rs ✓ (42ms)
▶ edit src/lib.rs ✓ (15ms)
▶ $ cargo test ✗ (1.8s)
```
- `✓` means the tool succeeded
- `✗` means the tool returned an error
- The duration shows how long the tool took
## Token usage
After each response, you'll see a compact token summary:
```
↳ 3.2s · 1523→842 tokens · $0.0234
```
Use `--verbose` (or `-v`) for the full breakdown including session totals and cache info.
This shows:
- Wall-clock time for the response
- Input→output tokens for this turn
- Estimated cost for this turn
## Interrupting
Press **Ctrl+C** to cancel the current response. The agent will stop and you can type a new prompt. Press Ctrl+C again to exit.
## Inline @file mentions
You can reference files directly in your prompts using `@path` syntax. The file content is automatically read and injected into the conversation — no need for a separate `/add` command.
```
> explain @src/main.rs
✓ added src/main.rs (250 lines)
(1 file inlined from @mentions)
> refactor @src/cli.rs:50-100
✓ added src/cli.rs (lines 50-100) (51 lines)
(1 file inlined from @mentions)
> compare @Cargo.toml and @README.md
✓ added Cargo.toml (35 lines)
✓ added README.md (120 lines)
(2 files inlined from @mentions)
```
**How it works:**
- `@path` — injects the entire file
- `@path:start-end` — injects a specific line range
- If the path doesn't exist, the `@mention` is left as-is (it might be a username)
- Email-like patterns (`user@example.com`) are not treated as file mentions
- Images work too: `@screenshot.png` inlines the image into the conversation