America's No. 1 app is banned from America's biggest store

A No. 1 app that cannot check out

Muse went live on 8 September as a free agent that reads email, books tables and buys on a user's behalf. It passed 902,000 downloads in six days and topped the free charts on both US app stores by Monday, the day Meta shares rose 11.43%, their best day in 13 months, on a Wells Fargo target raise to $796 from $640 ¹². Ask it for paper towels and the reply is a popup: "Continued access by an unauthorized AI agent violates Amazon's Conditions of Use" ³.

The fourth agent Amazon has shown the door

Amazon cut Muse off on Sunday night after Meta refused to drop the store from the agent's scope ¹³. It is the fourth outside agent Amazon has moved against in a year: Perplexity's Comet browser, sued last November, plus shopping agents from Google and OpenAI ³. Amazon won an injunction in March under the Computer Fraud and Abuse Act, lost it on 4 August when the Ninth Circuit ruled the user, not the agent, does the accessing, and was denied a rehearing on 10 September ³⁴. The Muse popup leans on terms of service, the claim the appeals court left open ³.

Amazon is defending the shelf, not the shopper

What Amazon is protecting earns twice: more than $68 billion of advertising revenue last year, which depends on shoppers seeing sponsored listings, and the recommendation funnel behind it ³⁵. Andy Jassy told investors in July that 350 million shoppers used Amazon's own agent over the past year and spend 40% more per order ⁶. Amazon's Buy for Me identifies itself to other retailers and lets them opt out; it says Muse does neither ³⁵. Meta plays landlord too, having barred rival chatbots from WhatsApp business messaging in January ⁶.

Meta guides to $130–145 billion of AI and data-center spending this year ¹, and spent $30.1 billion in the June quarter alone, nearly five times the level of early 2024 ⁷. Muse is the product meant to answer for that bill, and it cannot buy at the largest online store in the US ⁶.

The user hands over the keys

The third party in this fight is the user. Muse signs people up by default for training-data collection and keeps proposing connections for bank balances, passport expiry dates and whole inboxes; Meta says its controls put people "absolutely in charge" ⁸. Privacy groups call the defaults a repeat of manipulative tactics ⁸, and the review was still climbing r/technology on Monday ⁹.

The agent gets carded at the door, or the walls hold

One ending is standards. Visa, Mastercard and Ant International said on 10 September they are writing common rules so merchants can recognize an agent at the door, close to Amazon's stated price of identification plus authorization ⁶¹. The other is walls: agents shop only where platforms permit, and Muse already pays through Stripe's Link with single-use card numbers everywhere else ¹⁰. The open question, as the participants themselves frame it, is whether access standards can be agreed that do not constrain what agents may do ¹¹.

Watch Wednesday night

Meta Connect opens Wednesday with a 7 p.m. Eastern keynote, where the first Muse usage numbers would land if Meta has them ². Amazon says the companies are talking and declines to say whether it will sue ³. Amazon is not blocking the future of shopping; it is reserving it.