Disclosure first, because it matters for how you read this: I'm the CTO of UniPaaS, an FCA-authorised payment institution, and we build paas.build. We also built the index this post is about, and yes, our own site sits at the top of it. So read everything below with that in mind. To make it fair I'm publishing the full rubric and every site's evidence, so you can check the math or disagree with it. I'll also point out where our own scoring is weak.
The question
AI agents are starting to buy things. Not "soon", now: people are wiring up assistants that book, subscribe and pay. So I got curious about a boring but important question. If an agent lands on a website, can it actually figure out what the site does, find the thing to buy, and pay? Or does it hit a wall of JavaScript and marketing copy?
There's already solid work on the retail side of this. Digital Commerce 360 and ReFiBuy rank the top 1000 stores for AI shopping readiness, and a few others score individual ecommerce sites. I wanted to look one layer down, at the infrastructure: the app builders, the payment providers, and the AI companies themselves. If the tools and the rails aren't agent-ready, the stores sitting on top of them can only get so far.
