Last 20 action entries

How Libretto Works

• Libretto is a CLI for exploring live websites and building or debugging reusable browser automation scripts.
• Use Libretto commands to inspect the site and open pages, observe state, inspect requests, and prototype interactions.
• Libretto work must end in script changes. Create or edit the workflow file instead of stopping at interactive exploration.

Shipped Source & Documentation

Read references/shipped-source-and-documentation.md for shipped source details, published documentation links, and implementation context beyond what this skill file covers.

Default Integration Approach

1. Call the site's fetch/XHR endpoints via browser-context fetch().
2. If references/site-security-review.md (assess only once per site) rules fetch() unsafe, passively capture responses with page.on('response', ...)
3. Fall back to Playwright UI automation.

Mix strategies freely across steps on a site.

Prefer to enter sites at a user-facing URL (homepage, login, etc.) on the first navigation — deep URLs on a cold session are commonly blocked by edge bot protection.

Always declare that entry URL as workflow startUrl. Do not open the same URL again with page.goto at the top of the handler when Libretto launches the browser; Libretto loads startUrl before the handler runs (and before CDP attach on Kernel / cloud providers). run --cdp attaches without navigating, so leave the existing page as-is or navigate inside the handler.

CAPTCHA Handling

• If a CAPTCHA, Cloudflare challenge, or similar bot check appears in a local Chromium session, try to solve it in the visible browser and continue from the solved state.
• If the same challenge appears while the session is using a hosted browser provider, wait up to 2 minutes for automatic CAPTCHA handling before deciding the workflow is blocked.
• When a CAPTCHA was observed during exploration, generated workflow code should include an explicit timeout wait at that point with a short comment linking to the hosted platform stealth docs. Follow references/code-generation-rules.md for the code shape.

Setup

• Use the package manager convention for the target project. The examples use npx libretto; pnpm, yarn, and bun projects should use their equivalent package-manager execution form.
• Use npx libretto setup for first-time workspace onboarding. It installs Chromium and syncs skills.
• Use npx libretto status to inspect open sessions without triggering setup.
• Use npx libretto update to upgrade the project-local Libretto package. Use npx libretto update --dry-run to preview the package-manager command first.

Experiments

• Use npx libretto experiments to list internal feature flags and npx libretto experiments describe <name> for usage notes when an experiment is enabled.

Run Modes