Amazon shuts Meta's Muse out of its store with a terms-of-service popup

A shopper who asked Muse to place an Amazon order on Sunday night got a notice instead: "Continued access by an unauthorized AI agent violates Amazon's Conditions of Use, to which our customers have agreed" ^[2]. Meta never signed that agreement. The shopper did.

The block is built on that sentence. Meta says Muse runs on a secure virtual machine with its own browser and checks with the user before sensitive actions like sending an email or making a purchase ^[14]. Muse does its shopping inside the user's session, as the user. In the Perplexity case, the Ninth Circuit held on Aug. 4 that the user and not the AI company was the party accessing Amazon's computers under federal anti-hacking law ^[7]. So the message Muse users see does not accuse anyone of hacking; it cites the Conditions of Use ^[11].

The timing is tight. Meta launched Muse on Sept. 8 as a personal agent for multi-step tasks, connected to email, calendar, payments, dining and shopping ^[12]. Two days later, on Sept. 10, the court denied Amazon's petition for rehearing, leaving contract and terms-of-service claims as the avenue still open to it ^[9][19].

On credentials, the two companies are describing different things. Amazon says Muse can reach account pages and order history when a customer prompts it ^[22], and that an agent which does not announce itself amounts to an undisclosed third party moving through customer accounts, processing transactions and handling sensitive data without Amazon's knowledge or consent ^[23]. Meta has said that credentials a user shares "go into secure storage, so Muse can use them without seeing them, including passwords a person types into the browser themselves" ^[8]. Amazon objects to the storing and to the session it cannot see into. GeekWire reported that Meta did not immediately respond to a request for comment on Sunday night ^[10].

Amazon's own comparisons are food delivery apps and the restaurants they take orders for, and online travel agencies and the airlines they book ^[5]. Both arrangements run on a contract between the two sides. Amazon's advertising revenue works out to more than $186 million a day ^[20], and an agent clicking through a reorder skips the sponsored results a shopper would scan.

These two already do business with each other. Amazon products have been purchasable inside Facebook and Instagram since 2023, and Meta signed a multibillion-dollar deal in April to run agentic AI workloads on Amazon's cloud ^[17]. Amazon said on Sunday it is in direct conversation with Meta, and declined to comment on whether it would take legal action ^[18]. Its spokesperson said: "Agentic third-party applications such as Muse have the same obligations, and we've requested that Meta remove Amazon from the experience" ^[4].

If you are building a buy-on-my-behalf feature, sort every destination on two questions: whose account the agent signs into, and whether the store has said yes in writing. Identified agent with an agreement is the delivery-app arrangement Amazon endorsed. Identified agent without one gets filtered by name, and you learn that during integration instead of after launch. An agreement plus an anonymous session is a support problem you volunteered for. An anonymous session with no agreement is where Muse was on Sunday night, and Amazon has run this play before: over the past year it sued Perplexity over the Comet browser and moved to block shopping agents from Google and OpenAI ^[15]. An Amazon spokesperson said: "We think it's fairly straightforward that third-party applications that offer to make purchases on behalf of customers from other businesses should operate openly and respect service provider decisions about whether or not to participate" ^[3].