The Singular Interface Experience & The Ive Phone
APIs over UIs. Intent over navigation. Agents over users... If you run a business that relies on the web, maybe you’ve got 12 months to make your systems LLM-first and agent-optimized.
We seem to be entering a new phase in the history of the web. A period where the first point of contact won’t be a search engine or a website—it’ll be a single (and victorious) LLM. Over time, our use of traditional search, apps, and websites will likely significantly drop. Instead, this front-line interface will act on the user's behalf, calling on services like Amazon, Expedia, and Google Claude (!) —delivering results without the user ever leaving the chat.
[Discuss the topic of this newsletter on LinkedIn]
The Singular Interface Experience (SIE)
I'm calling this the Singular Interface Experience (SIE). It’s not a future scenario—it’s happening now. While most people are still accessing services through browsers, that’s quickly changing. AI agents are starting to handle those interactions instead. They don’t visit your homepage. They don’t care how slick your navigation is. They go straight to your systems and ask:
Can I get the data I need? Can I complete this task? Can I act on behalf of the user?
If you run a web-based business or you create digital advertising, I'm thinking that you have 12 months to adapt. You probably need to build for AI-to-AI interaction. That means exposing your services through APIs that large language models can read, query, and transact with directly. Not doing so means risking invisibility in this new layer of the internet.
This isn’t just a technical challenge. It’s a business one. If your competitors become LLM-readable before you, they will capture the first wave of delegated intent—before the user ever reaches a screen.
I'm thinking of this as the Singular Interface Experience (SIE)—a paradigm where users engage through a unified, intelligent interface that replaces traditional app and web-based interactions. At first we'll interface through our web browsers but later through our phone, gadgets ands IOT devices. This interface will be omnipresent, intuitive, and action-capable.
Early Signals
A clear sign of what’s coming is the travel booking feature that Perplexity is testing with Expedia. As shared by Simon Taylor, it’s already live for some users. You don’t need to browse hotel listings, mess with filters, or second-guess reviews. You just ask:
“Find me a hotel in Amsterdam with a serious gym, walkable to conference venues, under €300/night.”
Thirty seconds later: a solid recommendation. The hotel they picked matched what the user already books manually. No scroll fatigue. No fake reviews. No misleading images. The AI acts as a proxy—filtering and selecting on your behalf. It even completes the payment via Stripe.
You’re not going to Expedia. Your SIE assistant is.
What Will Happen to Claude, Manus, Perplexity, and the Rest?
In the '90s, Google changed how search worked and quietly won the race. As Google took over, most of its competitors faded. Some became backend services for others. A few were absorbed into larger systems. Most simply disappeared.
I think ChatGPT is in that same dominant position now. And like the other players during the Google era, Perplexity, Claude, and others may need to pivot. Some will stick around, powering niche capabilities. Others will become utilities called upon by the dominant interface.
And Then There’s Hardware
We know that iPhone designer Jony Ive is building a device with OpenAI and this matters. That product will likely assume this kind of singular interface experience from day one. No apps. No browser. No clutter. It will expect users to speak or write and then deliver results from a world of connected services.
And this shift won’t stop at the device level. Perplexity is reportedly negotiating to be the default AI interface on Samsung phones. It’s like watching the Google/Apple search deal happen again—but this time, for the next generation of interaction.
Implications for Designers, Developers, and Businesses
If your customer is no longer the end user but the AI working for them, everything about your product strategy changes. These are topics that the PSFK team are talking to our clients about when it comes to AI to AI experiences:
APIs over UIs: Build clear, callable endpoints. Prioritize machine-readability over human navigation.
AI-to-AI interfaces: Your service needs to talk cleanly to other systems. Think about function chains, not clicks.
Deprioritize surface UX: Your homepage may matter less than the structure behind your booking or pricing engine.
1. Design for Intent, Not Clicks
Most APIs assume a developer will use them. That’s not enough. To be usable by an LLM, they need to support:
Natural-language-to-function mapping (“Book me a table at 7pm” → /reservations/create)
Flexibility in handling vague or incomplete requests
Helpful error messages that guide the AI toward a better query
2. Public, Well-Documented APIs
LLMs work best with structured documentation. If you want to be accessible to ChatGPT:
Use OpenAPI 3.0+ specs
Include examples and clear parameter descriptions
Host your docs at a public URL
Keep authentication simple and well-described
(For reference: OpenAI plugins are just OpenAPI-based APIs with a manifest file.)
3. Conversational Transaction Support
You’ll want to support:
Search: /products/search?query=lawnmower
Availability: /inventory/check?product_id=123
Booking: /appointments/book
Checkout: /checkout/start
Make responses clean and structured (JSON). Include backup options when something’s unavailable. Deliver complete answers—no pagination, no partial info.
4. Think Modular and Composable
Let the AI string together simple actions. For example, in travel:
/search-flights
/book-flight
/get-baggage-policy
Each service should be designed as a single action in a larger sequence the AI can build.
Shopify Gets It
Shopify is already showing signs of where this is headed. Its ChatGPT plugin started as a product discovery tool. But its architecture—and Shopify’s secure checkout—suggest it won’t stop there.
We’re not far from a future where someone asks, “Find me a leather tote under $200,” gets three great picks, chooses one, and completes the transaction—without leaving the chat. That means purchases, upsells, and post-purchase support could all be handled in one interaction. Shopify’s infrastructure and OpenAI’s function-calling make that not just possible—but likely.
In Closing
The web isn’t disappearing—it’s shifting roles. It’s no longer the main event, but the infrastructure underneath. Interfaces powered by AI will sit on top, mediating how people access services, content, and commerce.
That means your website may no longer be the front door to your brand. The interface is. And whether or not your service shows up in that conversation will come down to how well your systems are built for AI-to-AI interaction.
Piers Fawkes, PSFK / Service Buddy
[Images are AI generated, obvs]
[Discuss this newsletter on LinkedIn]
