A Calculator on a Throughline

Live in twenty-six minutes

The AI found the model in the record of the earlier chat and took its page apart into a page, a stylesheet and a script, so that the page could forbid every script but its own. It wrote the decisions first: one intent, one thing the page would never do, and nine requirements each with a test, from "anyone can read it and nothing asks who they are" to "a new build is seen on the next load". Then the image the page is served from, the pipeline that builds and scans it, and the few lines the hosting needs to route a name to a running thing. The certificate and the public address already covered any name beneath the register's, so the page needed neither; only a route.

Twenty-six minutes after the request the page answered from the public internet, and the AI checked it from outside: the security headers, the redirect from plain to encrypted, the health check, the page in a browser with no errors. That figure is from the timestamps of the session record. It could have been an hour; it was short because the register had already paid for the hosting.

Reshaped by the person who asked for it

Then the person used the page, and it changed eleven more times before the evening ended. Each change went the same way. He wrote a line or two; the AI wrote the decision and its test, changed the page, checked the record, and rolled the page out; the next line usually arrived before the last change had landed. In the order they came:

• "A little asymmetry." In the model one entrance's cameras could be down for a day and the other's could not. Both could, within the hour.
• Light and dark. The page followed the reader's system; he wanted a choice. It got one, kept in the reader's browser and applied before the page first paints.
• A fault the AI found in its own work. The network in front of the page keeps a copy of the stylesheet and the script for four hours. A returning reader could run last hour's script against this hour's page, and a new slider would silently do nothing. Every file is now named by its own contents, so a changed file has a new name, and the build fails if a name is left unstamped.
• Fewer sliders. Eight was too many. He designed the replacement in one message: one rate by default; a rate for each entrance behind a control; a rate for each camera behind another; and, at either level, entries and exits separately behind a switch. The values at each level stay put while another is shown.
• Two features removed. A setting that let the two cameras at one entrance fail together was "too complicated, and actually shifts responsibility to the number plate". Out. The offline-day settings "over-complicate it too". Out. Each removal is a decision on the record with his reason kept beside it, so the next person to wonder where a setting went can read why.
• Economics. A slider for how many drivers make two visits in a day, and from it the number of wrong notices a year and what they come to at the charge on the notice and at the reduced charge for paying promptly. He read the first wording and found it "a little provocative". It now calls itself an illustrative estimate of the reader's own choices, and both charges are inputs.
• Photographs. He had taken five on site. The AI blurred every number plate beyond reading, cropped his thumb out of one, straightened the two signs into flat boards and typed out their wording in full, so a reader can search it and a screen reader can say it. Hovering over a camera on the page's map now shows its photograph. The originals stay outside the record and are never published.
• Order and defaults. The signs moved to the end. Every rate now starts at three per cent, and the wide-angle camera at one hundred, because it reads no plates; so the headline reads the same at every level until a slider moves.
• One sentence at the top. The two visits are each shorter than the thirty-minute limit, including the drive in from the entrance and back out to the exit.
• Remembered settings. Every slider, switch and choice is kept in the reader's browser and there on the next visit, with a note saying so and a link to reset. "No need for an accept toggle": it serves only the reader, and nothing leaves the browser.

The map, and a tool that fell out of it

Between the sliders and the economics he asked for a map of the car park in front of the store, so the cameras could be marked on it. The AI drew one from open map data: the store, its car park, the roads and paths, and each place where the car park's roads meet the public road, labelled so he could point at them. Then it served him a page beside the map where he clicked where each camera is mounted and set the direction it looks, how wide, and how far. He placed three and said "done". The map went onto the page with the cameras numbered and a shaded wedge for what each can see. It is not reproduced here: a map names roads, and roads name the place.

His next message was that the map and the placement tool were "amazing, please capture it somewhere so we can use it again for different sites". So the drawing code came out of the page's repository into a tool of its own, with five commands, a record of eighteen decisions and eight tests, and the page's own map was redrawn by the tool the same evening; the hand-made version was deleted. The tool found two faults in itself the moment it ran on the real data. It listed two junctions the picture did not show; then, told to keep to the picture's frame, it dropped a junction that sat exactly on the edge. The tests caught the second.

Signing, and a fault in the process

Some way into the evening the person signed the thirty-two decisions then on the record, without saying he had. The AI's next save of its own work swept those signatures up with it, so the record of who signed what sits, in the history, under the AI's name. The signatures themselves are intact and carry his name; the presentation is wrong. The rule that stops it happening again, name each file you save in a record you share, is now written down where the AI will read it at the start of its next session.

Minutes later the AI changed the words of a decision he had signed, to set the new defaults he had asked for, and the tool said the signature no longer matched. It said so again when the note about remembered settings changed what the page says it keeps. He signed both again, and the eight new decisions with them, in one command on a hand-off; then the tool's eighteen in one more. That the tool reported the moved words within seconds is what this example has to show for the method. That the person signed thirty-two decisions in one go, and later ten and eighteen, leaves open the question the second example left open.