Quickstart

Open New session

Click New session at the top of the sidebar, or press ⌘N on macOS and Ctrl+N on Windows and Linux. The screen asks “What should we work on?” above a composer. Under the composer you choose where the session works and which agent runs it.

Choose a project

Click the folder button under the composer, which reads Choose a project at first. Pick a recent project, or Open project… (⌘O or Ctrl+O) to add a folder. The agent works in that folder. To just ask something, pick No project, and the session runs in a scratch folder of its own.

Choose an agent and model

Click the agent button on the right, which reads Choose an agent at first. The menu lists your agents on the left and the chosen agent’s models, reasoning level and switches on the right. The mode menu sits beside the button.

The menu lists the agents installed on your computer. Claude Code shows Sets up on first use until Kettu has installed what it needs. If an agent you want is missing, click Set up agents…, or install it in Settings › Harnesses (see Install). To start with the same agent every time, set Settings › General › Default agent.

Sign in if the agent asks

An agent that needs a sign-in shows Sign in in the menu. Sign in… opens its page in Settings › Agents, where Sign in in terminal runs the agent’s own sign-in command in Kettu’s terminal. Kettu never sees your credentials.

Send your first message

Describe the task and press Enter. To send with ⌘Enter or Ctrl+Enter instead, change Settings › General › Send with. The + button adds files, photos or a folder, you can paste images, and @ mentions a project file. The session starts with this message and appears in the sidebar under its project.

Answer permission requests

Before the agent runs a command or changes a file, it asks you in a card in the conversation. Click an option, or press 1 to 4 while the composer is empty. See Permission requests.