# GPT CLI (Rust)

A lightweight command-line interface for chatting with AI models (OpenAI and Anthropic), written in Rust.

This is a Rust rewrite of the original Python gptCLI, providing the same functionality with improved performance and memory safety.

## Features

- **Multi-provider support** - Works with both OpenAI and Anthropic models
- **Session persistence** - Conversations are automatically saved and can be resumed later
- **Model switching** - Change models on the fly with interactive selection
- **Web search** - Enable web search tool for OpenAI models (when supported)
- **Reasoning summaries** - Enable reasoning summaries for compatible OpenAI models
- **Interactive commands** - Full set of slash commands for session management
- **Cross-platform** - Runs on Linux, macOS, and Windows

## Installation

### Prerequisites

- Rust 1.70 or later
- API keys for the providers you want to use:
  - `OPENAI_API_KEY` for OpenAI models
  - `ANTHROPIC_API_KEY` for Anthropic models

### Build from source

```bash
git clone <repository-url>
cd gpt-cli-rust
cargo build --release
```

The binary will be available at `target/release/gpt-cli-rust`.

## Usage

```bash
# Run with default session and model
./target/release/gpt-cli-rust

# Start with a specific session
./target/release/gpt-cli-rust --session my-session

# Start with a specific model
./target/release/gpt-cli-rust --model claude-3-5-sonnet-20241022

# Combine options
./target/release/gpt-cli-rust --session work --model gpt-4o
```

## Supported Models

### OpenAI
- gpt-4.1
- gpt-4.1-mini
- gpt-4o
- gpt-5 (default)
- gpt-5-chat-latest
- o1
- o3
- o4-mini
- o3-mini

### Anthropic
- claude-3-5-sonnet-20241022
- claude-3-5-haiku-20241022
- claude-3-opus-20240229
- claude-3-sonnet-20240229
- claude-3-haiku-20240307

## Commands

### Chat Commands
- Type normally to chat with the AI
- Use `/help` to see all available commands

### Session Management
- `/list` - List all saved sessions
- `/new <name>` - Create a new session
- `/switch [name]` - Switch to another session (interactive picker if no name)
- `/delete [name]` - Delete a session (interactive picker if no name)
- `/clear` - Clear current conversation

### Model Management
- `/model [name]` - Switch model (interactive picker if no name)
- `/models` - List all supported models

### Features (OpenAI only)
- `/tool websearch on|off` - Enable/disable web search
- `/reasoning on|off` - Enable/disable reasoning summaries
- `/effort [low|medium|high]` - Set reasoning effort level (GPT-5 only)

### Other
- `/help` - Show help
- `/exit` - Exit the CLI

## Environment Variables

- `OPENAI_API_KEY` - Your OpenAI API key (required for OpenAI models)
- `ANTHROPIC_API_KEY` - Your Anthropic API key (required for Anthropic models)
- `OPENAI_BASE_URL` - Custom base URL for OpenAI API (optional, for proxies)
- `DEFAULT_MODEL` - Default model if not specified (default: gpt-5)

## Session Storage

Sessions are stored as JSON files in `~/.chat_cli_sessions/`. Each session contains:
- Conversation history
- Current model
- Feature settings (web search, reasoning)
- Metadata (last updated time)

## Differences from Python Version

While functionally equivalent, this Rust version offers:
- **Better performance** - Faster startup and lower memory usage
- **Enhanced safety** - Rust's type system prevents many common errors
- **Improved error handling** - More detailed error messages and recovery
- **Modern UI** - Better terminal colors and interactive selection
- **Cross-platform** - Single binary that works across platforms

## Development

### Project Structure

```
src/
├── main.rs           # Entry point and CLI argument parsing
├── cli.rs            # Main CLI loop and command handling
├── core/
│   ├── mod.rs        # Core module exports
│   ├── session.rs    # Session management and persistence
│   ├── client.rs     # API clients for OpenAI and Anthropic
│   └── provider.rs   # Provider definitions and model lists
└── utils/
    ├── mod.rs        # Utility module exports
    ├── display.rs    # Terminal display and formatting
    └── input.rs      # Input handling and interactive prompts
```

### Building

```bash
# Development build
cargo build

# Release build (optimized)
cargo build --release

# Run tests
cargo test

# Run with debug output
RUST_LOG=debug cargo run

# Format code
cargo fmt

# Check for issues
cargo clippy
```

## License

This project maintains the same license as the original Python version.