Quickstart

Use this guide when you want the fastest path from zero to a working CLI session, ready to start building with Cosine agentically.

1. Install the CLI

Choose one install method for your platform.

macOS or Linux

brew install CosineAI/tap/cos
cos --version

Linux alternative

curl -fsSL https://cosine.sh/install | bash
cos --version

Windows

winget install Cosine.CLI
cos --version

If you need direct download instructions or dependency notes, see Install & Authenticate.

2. Sign in

cos login

This opens your browser and connects the CLI to your Cosine account.

3. Open your repository

Change into the project directory you want to work in:

cd /path/to/project

If you want Cosine to create repo-local config files, run:

cos init

4. Start the CLI

cos start

This opens the interactive terminal user interface (TUI) in your current repository.

5. Try your first task

Inside the CLI, try a concrete prompt such as:

• Explain the architecture of this repository
• Find the authentication flow and summarize it
• Add a test for the date formatting utility

You can also run a one-shot task from the shell:

cos start --prompt "Explain the main entrypoint of this repository"

6. Learn the next layer

• Overview — Understand the product and mode model
• Commands — See the main commands and look up flags such as --cwd, --model, and --auto-accept
• Modes — Understand Manual, Auto, Plan, and Swarm