Page Automation Primitives

Agent calls page.goto('https://shop.example/cart') and immediately calls page.click('#checkout').

Pass wait_until='networkidle' or 'domcontentloaded' explicitly per the target's loading pattern. SPAs may need explicit wait_for_selector on a post-mount anchor — do not rely on the default 'load' for a JS-heavy cart.

Form has input event listeners that validate on each keystroke (e.g., card-number spacing). Agent uses page.fill() and validation never fires.

Use page.type() (per-keystroke events) when the form depends on input events. Use fill() for non-event-driven fields (faster, atomic). Decide per field by inspecting the listener model via observe() or DOM inspection.

Operator uses page.click('button.btn-primary') on a Tailwind site where the class is shared by 12 buttons.

Prefer Playwright's role/text-based locators (getByRole('button', {name:'Checkout'})) or Stagehand act() for resilience to class refactors. Avoid brittle class selectors as the primary target.