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.

Work with Git

When Cosine edits files in a Git repository, it can create an Agent Commit at the end of each editing turn so those changes stay visible, reviewable, and reversible in your normal workflow. If you prefer, you can also disable this behavior.

See Agent Commits for review and recovery.

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