tensteps.

Quickstart

Run Tensteps against any site from your own machine. You need Node.js 20 or newer and an Anthropic API key.

1. Get an API key

Create a key in the Claude Console and set a monthly spend limit there while you're at it. Then:

export ANTHROPIC_API_KEY=sk-ant-...

2. Describe what to test

Create tensteps.yml in your project's root:

# yaml-language-server: $schema=https://tensteps.ai/schema/v1.json
version: 1
studies:
  - name: signup
    objective: "Create a new account"
    start_path: /signup
    success:
      url_matches: "/welcome"
    sessions: 4

An objective is the goal in plain words, the way you'd say it to a person. success is how Tensteps knows they made it: a URL, visible text or a visible element. The first line gives VS Code (with the YAML extension) autocomplete and checking for every option.

Check it:

npx tensteps@beta validate

3. Run it

npx tensteps@beta run --url https://your-preview.vercel.app --open

The first run downloads Chromium (about 150 MB, once). Tensteps shows the plan and a cost estimate, asks before it starts, then prints each persona's outcome as it finishes. --open opens the HTML report when it's done.

Runs are saved in .tensteps/runs/<run id>/: report.html, run.json, one JSON file per session, and the screenshots. Add .tensteps/ to your .gitignore.

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