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Lasso is a coding agent that runs in your terminal. It comes with the cowboy CLI, so once you’ve installed the CLI you already have it. It also knows Cowboy from the start: in a Cowboy project, it loads a skill for building, testing and deploying actors. You describe the actor you want, and it writes the code and tests it on your machine. You start it with lasso. cowboy console is another name for the same agent.

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1. Connect a model

Lasso runs on your machine, but the thinking is done by an AI model hosted elsewhere, so it needs a key to reach one. It connects through OpenRouter, a service that gives you one key for many models. You pay OpenRouter for what you use, separately from your Cowboy wallet. Paying for models from your wallet is coming soon. Create a key on OpenRouter, then give it to Lasso by setting LASSO_API_KEY. This command waits for you to paste the key and press Enter. Nothing shows as you paste, and the key stays out of your shell history:
That lasts until you close the terminal. To have it in every terminal, set LASSO_API_KEY in your shell’s startup file.

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2. Start it in a project

Create a project, and check that Lasso is set up. This doesn’t call a model, so it costs nothing:
Output
--trust tells Lasso it may read this folder, and remembers that. Skills counts what Lasso can use, including the Cowboy skill, and /skills lists them. Model is OpenRouter’s name for the model in use. If it says (no channel), Lasso didn’t find your key. This check doesn’t test the key itself: a wrong one shows up as an authentication error on your first prompt. To choose another, start with lasso --model <id>, using any id from OpenRouter’s list. Now run lasso to start a session, and say what you want:

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3. Stay in control

Lasso reads and edits files in the project folder. On macOS its commands run in a sandbox with no network, and on Linux it asks before each one. It asks before anything that needs the network, such as a deploy, so you see what’s about to happen first. A deploy pays from your Cowboy wallet, so create and fund one before you ask for it. Your conversation, including file contents and command output, goes to the model provider, so keep private data out of the project. These are the commands you’ll use most inside a session: From your shell, lasso -c continues the latest session in the folder, and lasso -p "<prompt>" runs one prompt without opening a session.

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