Get Started

Fusion is a terminal-first AI coding agent designed for rapid setup and maximum autonomy.

Quickstart

Install fusion globally and initialize your first interactive session:

# 1. Install globally via npm
npm i -g @fusioncode/cli

# 2. Authenticate
fusion login

# 3. Launch interactive TUI
fusion

Interactive Auth Flow

When running fusion login, Fusion opens your default browser for seamless OAuth authentication:

$ fusion login

  Initializing Fusion login session…

  Opening browser to sign in to Fusion…
  If browser does not open automatically, visit:
    https://fusioncode.app/cli-auth?token=...

  Waiting for authorization…

  ✓ Logged in as user@example.com
    API key saved to: ~/.fusion/config.toml

  You can now run `fusion` to start the AI agent.

First Commands

Once logged in, start interacting with Fusion in any directory:

# Interactive TUI mode
fusion

# Single-turn prompt (Headless mode)
fusion -p "fix lint errors in src/index.ts"

# Minimal mode (ideal for mobile / small screen terminals)
fusion --minimal -p "explain the main router workflow"

# Always approve execution (automation mode)
fusion -p "run tests and fix failing cases" --always-approve

Next Steps

Explore all Installation choices for macOS, Windows, Linux, and Android Termux.
Learn how to obtain and manage API Keys.
Configure custom API keys and providers in Configuration.
Connect Fusion AI Gateway to OpenCode or OpenClaw.
Learn advanced CLI flags and slash commands in CLI Reference.