Every business has one: the workbook that does the quote, or the roster, or the check, and that somebody breaks every second week by typing over a formula. It can be a small interactive tool instead — from one prompt, built to be handed to people who will never see the logic.
This is not about building an app. That article exists and its first rung covers the mechanics of a custom tool. This is about a much more common situation, and a different person: you are not a builder, you have a spreadsheet the team depends on, and you are tired of fixing it.
The quote workbook works perfectly for the person who built it. They know which cells are inputs, which are formulas, and that the yellow ones must never be touched. Then it goes to sales.
Sales pastes a value over a formula. Someone sorts a column and breaks the references. Someone “fixes” a rounding they did not like. Three versions circulate. Nobody knows which is current. Once a fortnight the owner rebuilds it from the copy they kept, and the cycle starts again.
Nothing about the logic is wrong. The problem is that a spreadsheet gives every user the same power as its author, and most users should not have it. What they need is the inputs, the result, and nothing else — which is the definition of a tool.
Each of these is a real business object, described the way that produces a working tool. Notice what the descriptions contain: users, inputs, the calculation in words, validation, and what happens when something is missing. Notice what they do not contain: colours, layout, or the word “beautiful”.
A quote calculator for our sales team. Inputs: quantity (whole number, 1 to 5,000), unit price in A$, delivery region (metro / regional / remote), and whether the customer has a trade account. Rules: trade accounts get 12% off the line total; delivery is A$0 metro, A$45 regional, A$120 remote; GST is added at 10% on the total after discount and delivery. Show the line total, discount, delivery, GST and grand total separately, and the grand total large. If any input is blank or out of range, show a plain message next to that field and do not calculate. Add a “Copy quote” button that copies a one-paragraph summary.
What sales gets: four fields and a number. What they cannot do: change the 12%, the delivery table or the GST rate, because those are not inputs. When the trade discount changes, the owner changes the tool once, and every copy of the old spreadsheet stops mattering.
A weekly capacity planner for an operations lead. Inputs: number of staff (0 to 40), hours per person per week (0 to 60), planned leave hours for the week, and a list of jobs with estimated hours each (add or remove rows). Calculate available hours (staff × hours minus leave), committed hours (sum of jobs), and the gap. Show the gap in green when available exceeds committed by 10% or more, amber within 10% either way, red when committed exceeds available. Jobs with no estimate count as zero and are flagged. Show which jobs would have to move to bring the week back to green, starting with the largest.
This is the one that usually lives as a workbook with conditional formatting nobody understands. As a tool, the rule is in the description and the colours follow from it. The “which jobs would have to move” line is the useful bit that a spreadsheet makes people work out by hand.
A pre-submission checker for tender documents. Inputs: a checklist of twelve named items (each yes / no / not applicable), the submission deadline as a date, and today’s date. Rules: any “no” blocks submission and is listed at the top with the item name; “not applicable” requires a one-line reason or it counts as “no”; if the deadline is fewer than two working days away, show a warning in red regardless of the checklist. Output a single status — Ready, Blocked, or Ready with warnings — and the list of blockers. Add a button that copies the status and the blockers as plain text.
A checker is the most underrated tool in a business, because it turns a thing people forget into a thing that cannot be skipped. And it is almost impossible to build well in a spreadsheet, where a checklist is a column of cells that can be left blank.
Read those three prompts again and you will see the pattern the Academy teaches: who uses it, what inputs it accepts, the calculation in words, what must be validated, what to show when data is missing or invalid, and what the output is. That is the whole discipline. A prompt that describes a layout produces a page that looks like a tool. A prompt that describes behaviour produces a tool.
You will not get it perfectly right the first time, and you are not supposed to. The tool renders live in the chat; you use it, you say “the discount is applying before delivery, it should apply after”, and it changes while keeping the parts that were already right. That preview-and-steer loop is the actual method.
A tool that works when you use it is not a tool that works. Before it goes to anyone else, deliberately break it:
Then the test that matters more than all of those: hand it to one person who did not build it, say nothing, and watch. If they ask a question, the tool needs a label, not an explanation.
The Academy’s reference page puts it in one line worth keeping: a working preview is a testable artefact, not automatic production approval.
Every generated tool carries the same small set of controls, and the choice among them is the choice of where the tool lives:
| Control | What it does | Use it when |
|---|---|---|
| Save as AI Tile | Pins the tool to your tile dashboard beside the others | You will use it every week. The quote calculator, the capacity planner. |
| Open in new tab | Runs the tool full-screen in its own tab | You want to use it for a while, or show it on a call. |
| Save HTML | Saves the tool as a single file | You want to keep a copy, or hand a self-contained version to someone. |
| Convert to… Document | Turns the tool’s logic and output into a written document | The rules need to be in the procedures manual as words. |
| Convert to… Visualisation | Turns the numbers into a chart | The capacity gap is more useful as a picture in the Monday report. |
| Convert to… Code | Opens the tool as a code project in the editor | It has outgrown a single tool and needs to become a real application. |
That last row is the honest boundary. A live artefact is for a focused, single-purpose interaction. When the tool needs accounts, a database, several screens or a team of users, it is no longer a tool; it is an app, and the app article takes over from here.
None of this argues against spreadsheets. The person who owns the logic should keep the workbook, because a workbook is the best place to reason about logic. What changes is who receives it. The owner keeps the sheet; everyone else gets the tool; and when the logic changes, one thing is updated rather than nine emailed copies.
If the logic itself is the hard part — a real financial model, a rate library with history — that is the spreadsheet editor’s job and the accountants article covers doing it properly. The tool is the layer on top: the safe surface you hand to the people who should not be inside the model.
Live artefacts and custom tools are part of the Oppermind workspace today: describe the tool in chat, use it live in the reply, steer it, then save it as a tile, open it in a tab, save the file, or convert it to a document, a visualisation or a code project. The Academy course takes forty-two minutes and ends with a tested tool built for a real need; the reference page is the five-step short form — choose the surface, describe behaviour, preview and steer, test before customer use, publish deliberately.
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Whatever you’re here to make, make more of it.
A tool hides the logic, which is the point, and also the risk: nobody using it can see whether the 12% is still right. Put the owner’s name and a date on it. Review the rules when the business changes them, not when someone notices a wrong quote. And if the tool will handle customer information, treat handing it out as a deliberate publish with a decision about who can reach it and what it keeps, not as sharing a link. The Academy’s last step is called “export or publish deliberately” for exactly that reason.
A small interactive tool — a calculator, a planner, a checker — generated from a plain-language description and running live inside the chat where you asked for it. You can use it immediately, tell it what to change, and then save it as a tile on your dashboard, save it as a file, open it in its own tab, or convert it to a document, a visualisation or a code project.
When the person using it is not the person who built it. A spreadsheet handed to a colleague can be broken by a stray keystroke, a pasted value over a formula, or a sorted column. A tool exposes only the inputs that should change and validates them, so the logic cannot be edited by accident. Keep the spreadsheet for the person who owns the logic; give everyone else the tool.
Describe behaviour, not appearance. Who uses it, the inputs it accepts, the calculation in words, what it must validate, what it shows when something is missing or invalid, and what the result looks like. A prompt that describes a layout produces a page; a prompt that describes behaviour produces a tool.
Empty inputs, invalid inputs, unusually large or small values, a phone-sized screen, and what happens when the thing it depends on is missing. Then hand it to one person who did not build it and watch them use it without help. A working preview is a testable artefact, not automatic approval for production.
It can use whatever you give it, which is exactly why you should decide first what it is allowed to see. Build and test with realistic sample values, keep sensitive data out of the description, and treat a tool that will handle customer information as a deliberate publish with an access model, not a quick share.
The tools and figures described are illustrative examples, not templates for your business; discount rules, delivery charges, GST treatment and any rule you build into a tool are yours to determine and verify, and this article is not tax, accounting, legal or professional advice. Tools that handle personal or customer information are subject to your own privacy obligations. Oppermind platform prices are current as at 14 September 2026, are in Australian dollars, and are subject to the plan terms at checkout.
Describe the behaviour once, test the edges, save it as a tile — and stop rebuilding the workbook every fortnight.