page the live page
code what it built from the page
element table
also in the request
Jev picks, it never writes. Every step is a multiple-choice question the code builds from the live page; Jev answers with one option and a probability.
Step through a real run: the page, what the code built, what Jev answered. The logic here is scripts/core.mjs — the same file the skill runs.
Each place this implementation stops is a lesson about Jev.
The request asks for the operation and, speculatively, a target under every operation. The answer to the head that matches the chosen operation is used; the rest are discarded. Two dependent decisions, one round trip.
Not the DOM, not a screenshot. Whatever the observe step failed to capture, Jev cannot choose. Early on the login fields were labelled acct and pw, and Jev answered BLOCKED 0.31. Better labels fixed it.
text_values are supplied by the caller; Jev picks which one belongs in a field. A secret is typed only into password fields and never enters a request: Jev sees the field exists and whether it is filled.
An answer is a key into a table the code built. If it is not in the offered set, the code throws and nothing runs. Model output never becomes a selector, a coordinate or JavaScript.
So this skill offers the first 250 controls and warns when it skipped some. The Hacker News front page has 227. Larger pages need a first question that narrows to a region before this one.
Every step is an independent request. The only memory is the recent_actions the code chooses to send. A step is a few thousand input tokens; output is free.
Reference implementation, MIT. Read the code on GitHub. Jev is by TypeSafe.