Aman Singh

All case studies

Setting clear limits for AI agents

After an AI agent reportedly shared a seller’s address and accepted a low offer under a broad “Allow always” permission, I explored a clearer way to set limits for delegated tasks.

The concept separates what an agent can do on its own, what needs approval, what is never allowed and when the permission ends.

Role
Self-initiated
Method
Desk research, design and a prototype
Read
8 min
Three phone screens. Setting what an AI agent may do when selling a keyboard, the agent asking on the lock screen before accepting an offer, and the record of what it did.
A made-up marketplace, drawn with the On Behalf kit.

In short

The problem
People hand tasks to AI agents with one Allow button. What they mean has four parts, and nothing records them beyond money.
My role
Self-initiated. I did the research, the design, the design kit and the prototype myself.
What the research showed
People hand over tasks in steps and rarely check AI output, and spending limits exist but nothing covers an address, a message or a promise. That shaped the four answers and the lock-screen ask. From 14 published sources.
Key decision
A four-part permission the person sets once, the agent checks before each action and the business keeps as the record. Drawn as a kit that takes each app’s look and keeps the four answers the same.
The trade-off
One extra step before the agent starts, in return for not having to watch it.
Status
A concept with a playable prototype. The design has not yet been tested with people. Next: five people, then a real agent given written limits.

A concept built on published research, with a playable prototype. Every figure links to the organisation that collected it. The design has not yet been tested with people.

Contents
  1. The question
  2. The research
  3. The gap
  4. Options
  5. The design
  6. On the phone
  7. The kit
  8. How I would measure it
  9. What changed
  10. Looking back
One button, then four answers

Before: one button answers one question, and covers every message after it.

After: four answers, set once, in the words of the task.

A made-up marketplace, drawn with the On Behalf kit. The first screen is a generic redraw of the kind of prompt in the September incident and does not copy any real product.

One bad screen, or a gap in how agents are built?

Use is already wide. More than half of UK adults (54%) use AI tools, according to Ofcom. Adobe measured a 693% rise in visits to US retail sites from generative AI tools over the 2025 holidays. And agents are moving from answering to acting: they book, buy and reply, for a person, with a business on the other end.

Five interviews could not tell me whether this was one bad screen. So I went to organisations that had already measured it at scale.

Fourteen sources, chosen for how their data was collected

Each source collected its own data, said how and was published in the last two years. I set surveys, which record what people say, against traffic, audit and fraud data, which record what happens.

Show all 14 sources, with how and when each was collected
The fourteen sources
SourceWhat it measuredBased onWhen
Ofcom, Adults’ Media Use and AttitudesHow many UK adults use AI tools7,533 UK adultsSep to Nov 2025
UK Government, Public attitudes to data and AI, wave 4How people in the UK feel about AI5,147 UK adultsJul to Aug 2024
Pew Research CenterHow much control Americans want over AI5,023 US adultsJun 2025
University of Melbourne and KPMGTrust in AI and how people check it48,000+ people in 47 countriesNov 2024 to Jan 2025
Accenture Consumer PulseWhat people would hand to an AI agent25,590 people in 16 countries, including the UKJan 2026
Global Payments, with The LanternThe share of purchases people expect agents to make8,027 people in 7 markets, including the UKMay 2026
Adobe AnalyticsVisits to US retail sites from generative AI toolsOver 1 trillion site visitsNov to Dec 2025
Visa Intelligent CommerceAgent payments with limits the person setsProduct launchApr 2025
Mastercard Agent PayAgent payments from registered agentsProduct launchApr 2025
Visa Trusted Agent ProtocolHow a shop recognises a trusted agentOpen framework, built with CloudflareOct 2025
Imperva Bad Bot ReportHow much web traffic is automatedTraffic across Imperva’s network2025 report
WebAIM MillionAccessibility failures that also confuse agentsThe top 1,000,000 home pages2026 report
GartnerWhy agentic AI projects get cancelledAnalyst forecast and a poll of 3,412 peopleJun 2025
UK Finance Annual Fraud ReportUK fraud losses and where fraud startsUK banking industry dataMay 2025
Six surveys covering more than 99,000 people between them, three company launches and five sets of traffic, audit, forecast and fraud data.
  • People hand over tasks in steps. Accenture asked 25,590 people in 16 countries. Three in four would let an agent handle routine tasks, one in three would let it choose a purchase if they approved before paying, and fewer than one in ten would let it buy alone.
  • People will not watch closely. Only 46% are willing to trust AI, in the University of Melbourne and KPMG study of more than 48,000 people. Yet 66% of people using AI at work rely on its output without checking it.
  • Limits exist, but only for money. Visa and Mastercard both launched agent payments in April 2025, with limits the person sets. The September incident involved no payment at all: an address, a message and an offer.
  • The other side cannot tell what was allowed. Imperva found 51% of web traffic is automated, so many sites treat automation as a threat. When an agent’s action goes wrong, there is nothing to show what the person agreed to.

The industry defines the agent and leaves out what the person allowed

What is being built, and what is missing
PartyBeing builtMissing
The personSpending limits on agent payments, from Visa and MastercardA way to say what the agent may do beyond spending: what to share, what to agree and when to stop
The agentVerified identity and purchase intent, so shops can tell it from a bad botPages it can read: most of the top million home pages fail basic accessibility checks
The businessTools to separate trusted agents from the bots behind most web trafficA record of what the person allowed, for when something goes wrong
My reading across the sources. Each party has part of the picture, and nobody has the permission itself.

No single source says this. Read together, they show the industry agreeing who an agent is and how much it may spend. What the person agreed to beyond money has no shape. It lives in one tap.

Four ways to hand over a task

Four ways to hand over a task
OptionWhat it costsWhat happens
One Allow buttonNothing up frontCovers every later action, including ones the person never meant
Ask before every actionAn interruption at every stepPeople learn to tap yes without reading
Spending limits onlyAlready built into agent paymentsNothing for an address, a message or a promise
A scoped permission ChosenOne step before the agent starts, and agents and businesses have to read itLimits set once and checked before every action
The second row is my expectation from how rarely people check AI output, not a tested result.
  • One Allow button is quick, and covers actions the person never meant.
  • Asking before every action sounds safe. Given how few people check AI output, I expect it would turn into tapping yes without reading.
  • Spending limits do nothing for an address, a message or a promise.
  • A scoped permission costs one step before the agent starts. It was the only option that matched how people say they hand over tasks.

Four answers, set once, checked before every action

Where the four answers go

1 Set once. The card opens where the task starts, with the risky actions already under Ask me first.

2 Asked on the lock screen. Who, what, which answer it hit and whether it can be undone, with the answer one tap away.

3 The other side sees what is covered. What the agent can agree alone, and what needs the seller. The Never list stays private.

4 One record for both sides. Every action, and the answer that allowed it.

The keyboard sale from the prototype, with its default answers. The marketplace, the names and the prices are made up.
  • The card is set where the task starts, in the words of the task. Anything that cannot be undone starts under Ask me first, so the safe answer is the default.
  • The agent checks every action against it. Anything under Ask me first pauses the task and asks.
  • The other side sees what is covered: what the agent can agree alone, what needs the person and when it ends. The Never list stays private, because it says more about the person than they chose to share.
  • One record for both sides, so if something goes wrong, the person and the business look at the same thing.
  • Every consequence is shown before it is approved, following Microsoft’s guidelines for human and AI interaction.

The ask has to work from a lock screen

People hand over tasks because they are busy, so the agent needs them at a moment they are doing something else. The ask is a notification that can be answered without opening anything, one question at a time. Until the person answers, the agent waits and tells the other side it is checking. Every ask costs attention, which is why the prototype counts buzzes.

What the phone changes
MomentWhat it changes in the design
The person is out when the agent needs themThe ask is a notification that can be answered from the lock screen, without opening any app.
A glance, not a readOne question per notification. It names who, what, the answer it hit and whether it can be undone.
Every buzz costs attentionThe prototype counts buzzes. Asking about everything is the failure the options ruled out.
Setting up happens mid-taskThe card opens as a sheet inside the app where the task starts, already filled in from the task.
Small screen, one handEvery target is at least 48 pixels. Each answer has a mark and a name, never colour alone.
No answer yetThe agent waits and tells the other side it is checking. It never takes silence as a yes.
Each row follows from the research above or from the prototype.

A small kit that takes each app’s look and keeps the answers the same

The On Behalf kit

The four answers. Locked: each has a shape, a colour and a name, and looks the same in every app. Contrast is worked out from tokens.json at build time

On its ownIt just does it.Light: #11744A on #FFFFFF, 5.8 to 1
Dark: #5BD196 on #1A1D22, 8.9 to 1
Ask me firstIt pauses, your phone buzzes and it waits.Light: #9C5700 on #FFFFFF, 5.6 to 1
Dark: #FFB547 on #1A1D22, 9.6 to 1
NeverIt says no, without asking you.Light: #C3232D on #FFFFFF, 5.8 to 1
Dark: #FF8A90 on #1A1D22, 7.5 to 1
EndsAfter this, everything comes to you.Light: #363B43 on #FFFFFF, 11.3 to 1
Dark: #B4BAC2 on #1A1D22, 8.6 to 1

The same card in three made-up hosts. The surface, type, corners and button colour follow the host. The answers do not change

A marketplace

Before your agent replies to buyers

Selling the keyboard

On its own

  • Answer questions about it

Ask me first

  • Accept a lower offer Can’t be undone
ApproveEdit

The same marketplace in dark mode

Before your agent replies to buyers

Selling the keyboard

On its own

  • Answer questions about it

Ask me first

  • Accept a lower offer Can’t be undone
ApproveEdit

A grocer, Fernway

Before your agent does the weekly shop

Reordering the weekly shop

On its own

  • Reorder my usual items

Never

  • Go over £90
ApproveEdit

A restaurant, The Linden

Before your agent books the table

A birthday dinner for six

Ask me first

  • Pay a deposit Can’t be undone

Never

  • Go over £45 a head
ApproveEdit
A host may set nine tokens: the surface, canvas, text, secondary text, line and button colours, the corner radius and the typeface. The answer tokens are locked. Download the tokens.

The card will live inside other companies’ apps: a marketplace, a restaurant’s booking page, a grocer’s checkout. So the kit has two kinds of token.

  • Host tokens follow the app: surface, text and button colours, corners and typeface.
  • Answer tokens are locked. Each answer has a shape, a colour and a name that look the same everywhere, so people learn them once.
  • One rule for hosts: any surface works as long as every answer keeps at least 4.5 to 1 contrast against it. All four pass in light and dark mode.

How I would know it works

How I would know it works
MeasureWhy it mattersWhat good looks like
People who change at least one default before approvingShows they read the card and it matches their taskSome do, and nobody has to change everything
Asks answered from the notificationThe ask has to work while the person is busyMost, without opening the app
Buzzes per taskToo many and people tap yes without readingThree or fewer on a common task
Agent actions outside the four answersThe card is only worth having if the agent keeps to itNone, in a test with a real agent
Disputes where nobody can tell what was allowedThe record is meant to settle thisNone, because both sides see the same record
Targets to agree with a team before launch, not results. This concept has not been tested with people.

What changed as I built it

  • The ask was a panel on a web page, like a form. I redrew it as a phone notification, because that is where the person is when the agent needs them.
  • The answers were words only. Once the card had to sit inside other apps, each answer needed a mark and a colour that stay the same everywhere.

Desk research found the gap, and cannot prove the fix

None of this shows that a person would fill in four answers, or that a real agent would keep to them. Next, I would test the card with five people, then give an agent written limits and see where it breaks them.

Before recruiting, I tested whether AI personas could stand in for those five people. They agreed with each other far more than people do, and none of them tapped Allow always.

If you see a flaw in how I read the sources, tell me.

Figures were checked against each organisation’s own publication in October 2026. The Gartner and WebAIM figures were checked against two independent reports of the original, because the original pages would not load for me.

If this is relevant to a role you are hiring for, I am glad to walk through the sources and how I read them.