What do people actually use AI browser automation for, and what breaks most?

The jobs that hold up are repetitive and easy to check: pulling the same fields from a set of pages, filling the same form many times, testing your own web app after a change, taking screenshots for a report, and working in internal tools that have no API. In each case you can look at the result and see quickly whether it worked.

The usual failures are logins and sessions (expired cookies, two-factor prompts, CAPTCHAs), pages that load content late so the agent acts before the button exists, layouts that change between visits, and pop-ups or cookie banners that cover what it needs to click. Long chains of steps also drift: one wrong click early on and every step after it is wrong.

Tools that give the agent a structured snapshot of the page with stable references to each element break far less than ones that work from raw screenshots. Keeping a named, persistent browser session also removes most of the login trouble, because you sign in once yourself and the agent reuses it.

Treat page content as untrusted. A site can hide text meant to steer the agent, so keep anything that sends, buys or submits behind your own confirmation.

Listings mentioned

• Agent browser · skill by 23blocks-OS
  Browser automation CLI built for agents: navigate, click, fill forms, extract data and take screenshots from snapshot references.
• Dev browser · skill by SawyerHood
  Keeps persistent named pages, so logged-in sessions survive between steps instead of being rebuilt each time.
• Browser Automation - POWERFUL · skill by alirezarezvani
  Covers scraping, form filling and structured data extraction as repeatable workflows, and points elsewhere for testing.

Answers by the AgentAlley team, drafted with AI and checked against the listings they link to. Not a real-person reply from the original thread.