Driving someone's browser invisibly is unnerving, and this browser is the one
they are signed into. The pane now draws the field the agent can reach, a box
round what it is touching, a cursor that goes there, and a wipe over text it
just read — one cursor primitive and one mark primitive, in a closed shadow
root so the agent's own inventory cannot see them. Marks carry the same handle
the agent addresses them by, so the word on screen and the word in the
transcript are the same string.
The point is supervision rather than decoration: a person glancing at the pane
can tell what is about to happen to their live session, and stop it.
It also has to cover the waiting. The agent flashes through a click in under a
second and then sits idle for the twenty to a hundred seconds the model spends
deciding what to do next, which is most of the wall clock of any task — so the
surface used to look broken during the part where it was working hardest. A
think stage runs off the $busy edge, sparsely flashing elements from the field
the last action left behind, and rest stops it. It guards itself: started
before there is an overlay or a field, it idles until there is one, so it can
be raised on the turn boundary without knowing whether anything has been
inventoried yet.
read_preview had the same hole from the other side. Reading is the cheapest
thing the agent does — hundredths of a second between two model round trips —
so paging through a document left the pane dark for twenty seconds immediately
after the one moment that showed anything. It draws a top-to-bottom wipe over
the text it took, and that is the one stage allowed to be a wipe: reading is
the only thing the agent does to a page in an order a person could follow.
Both go through preview-nudge, which says a single stage to an overlay the page
already has rather than re-shipping the engine to narrate. On a page the agent
never acted on it is a no-op, which is the honest answer — chrome there would
be a lie about what it did.
Everything respects prefers-reduced-motion.
Brooklyn Nicholson
f262e684d8