Three Doors Into Seller Central

What changed

Amazon wrote the rule down

On March 4, 2026 Amazon added Section 19, "Use of Agents," to the Business Solutions Agreement every seller signs. It defines an agent as "any software or service that takes autonomous or semi-autonomous action on behalf of, or at the instruction of, any person or entity." That definition does not mention AI. A plain browser extension you click counts too.

Section 19 points to Amazon's Agent Policy, which sets four technical rules for any agent touching Amazon:

1. Identify itself in every web request, with its name in the user-agent string as Agent/[agent name].
2. Never hide that it is automated, for example by mimicking human typing or click speed, or by solving robot checks.
3. Answer any "are you a human?" check truthfully.
4. Never get around measures Amazon uses to block or limit agents.

Amazon can also tell an agent to stop, and a breach of the agreement can be treated as a material breach, the same path that leads to account deactivation. The same four rules now appear in the shopper-side Conditions of Use on amazon.com (last updated August 14, 2026).

Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 Chrome/141.0 Safari/537.36 Agent/[agent name]

The map

One wall, three doors

Picture Seller Central behind a wall. On one side is the part Amazon built for software. On the other is the part built for people with a browser. Software can still get in on the people side, but only by borrowing a person's login, and that is where the rules bite.

Door 1 · Designed for this

Apps on the API

The Selling Partner API exists for programmatic, systematic access. Repricers, accounting links, inventory tools and analytics dashboards connect here. Their developers register with Amazon, agree to Amazon's developer terms, and get only the permissions you grant. Bots and agents on this side are the point.

You probably have more of these than you remember, and the list is worth a look because every entry is a key to your account.

Check yours in two minutes

1. In Seller Central, open the menu and go to Apps and Services, then Manage Your Apps. It is also linked from Settings > User Permissions.
2. Read every name. An app can be listed under its developer's legal company name, which may not match the brand you know.
3. Revoke anything you no longer use. A tool you quit last year can still hold access today.

A seller who has been at this a few years can easily find a dozen or more apps on that list: accounting links, repricers, sourcing and analytics tools, lenders, print services. Many will be ones you stopped using long ago, which is exactly why the list deserves a regular cleanup.

One nuance: some Chrome extensions are also registered API apps. The list tells you what has API access. It does not tell you what that same extension does through your browser, which is Door 2.

Door 2 · Allowed with rules

Extensions using your login

When you are logged into Seller Central, your browser holds a session cookie. An extension can make requests with that cookie and read pages the way you would: eligibility checks, inventory screens, your own listing price. This is the consumer side of the wall. It is narrower than the API and was never designed for software, which is why Section 19 was written with tools like these in mind.

Nothing in the agreement bans this kind of tool. What the Agent Policy asks is that it be honest about itself. For an extension that is easy to do. It can tag its own requests with Agent/[name] and leave your manual browsing alone.

Profit Zones identifies itself with an Agent tag with our name on every Seller Central request it makes, on all ten marketplaces, since October 1, 2026. Only requests the extension starts are tagged; your own browsing is left alone. How Profit Zones accesses your data lists every Seller Central request it makes.

Ask every extension vendor

1. Do your Seller Central requests carry an Agent/ name in the user-agent? What is the name?
2. Do you stop, rather than retry or solve it, when Amazon shows a robot check or blocks a request?
3. Does anything run on its own in the background, or only when I click?
4. Does any of my Seller Central data leave my computer?

A vendor who has done the work will answer all four in one email. Silence or "we're not an agent" is an answer too, and it is the vendor's bet placed on your account.

Door 3 · Unannounced today

AI that drives a browser

This is the frontier: general AI assistants that open pages, read them and click for you. They come in two shapes. Some drive your own browser with your own login. Others run a cloud browser on the vendor's computers, where you sign in to Amazon inside their machine.

As of October 3, 2026. Atlas, OpenAI's former agent browser, was retired in August 2026. The "Claude" and "ChatGPT" research crawlers are a different thing. They do name themselves, and Amazon blocks them in robots.txt.

So who is responsible?

The AI company did not sign your Business Solutions Agreement. You did. Section 19 binds the seller, and it has no exception for "I only told it what to do" or for reading your own data. When Claude or ChatGPT drives Seller Central in your browser, Amazon sees your account doing something automated without the tag its policy requires. The breach, if Amazon calls it one, is on your account.

The court fight you may have heard about does not change that. In Amazon v. Perplexity, a judge blocked Perplexity's Comet agent in March 2026, and the Ninth Circuit vacated that order on August 4, 2026, reasoning that the user, not Perplexity, was the one accessing Amazon. That was a computer-crime case against the AI company. It says nothing that protects a seller under the seller's own contract, and by its logic the user is the actor. The case is now back in district court.

How big is the risk, really?

• Enforcement is discretionary. We found no credible public report of a seller deactivated for using an AI assistant in Seller Central as of this writing. Amazon's posture is still hardening on the shopping side: on September 20, 2026 it blocked Meta's Muse assistant from amazon.com under the customer Conditions of Use, saying it was unauthorized, did not identify itself, and appeared to capture customer credentials.
• Reading is low, changing is high. An assistant reading a report you could read yourself is the quiet end. An assistant changing prices, listings, shipments or settings at machine speed is the kind of semi-autonomous action the rule was written for, and it is where a mistake costs real money.
• Cloud browsers add a second risk. When you sign in inside a vendor's cloud browser, the AI never sees your password, but your logged-in session lives on their computer. The Business Solutions Agreement's Password Security section says you may not give your Seller Central password to a third party you have not authorized, and that you are responsible for anything done with it. It does not mention cloud browsers or new-device checks, so treat those as practical risks rather than a written violation. One catch many sellers miss: if your shopper account and your seller account share the same login, a "shopping" session in a cloud browser may also open Seller Central.
• Robot checks are a bright line. If an assistant solves or works around a robot check or a block on your account, it is breaking a written rule, not a gray one.

Can you make it identify itself?

Partly. A small Chrome extension can append Agent/YourName to every request to Seller Central. Run your AI assistant in a separate Chrome profile used only for agent work, with that extension installed, so your own browsing stays untagged. That satisfies rule 1 for a tool that drives your browser. It does not satisfy rules 2 through 4 by itself: the assistant still must not solve robot checks or dodge blocks, and Amazon may simply limit tagged traffic. It also does nothing for cloud browsers, which you cannot configure. We found no ready-made extension built for this yet.

What to do

A seller's playbook

1. Audit Door 1 this week. Open Manage Your Apps, recognize every name, revoke what you no longer use.
2. Ask your Door 2 vendors the four questions. Prefer tools that tag themselves, stop on a robot check, act only when you click, and keep your data on your machine.
3. Bring AI in through the official door. US Professional sellers using Claude can connect the Selling Partner plugin from Claude's Connectors today. Anyone else: export the report and give the file to your AI. That gets you the analysis with none of the access.
4. If you let AI drive Seller Central, keep it read-only and slow. A dedicated Chrome profile, the Agent/ tag, no bulk loops, no price or listing changes, and stop the moment Amazon challenges it.
5. Keep your seller login out of cloud agents. Cloud browsers are fine for public product research while signed out. Signing in as a shopper puts you under the same agent rules in the customer Conditions of Use, and if that login is also your seller login, keep it on your own computer.

Sources

• Amazon Business Solutions Agreement (US), Password Security section and General Terms Section 19 "Use of Agents" (effective March 4, 2026), and the Seller Central Agent Policy (Seller Central Help node GS83KH2MA7HM69PH, login required), read June 2026.
• Amazon Conditions of Use, Agent Terms (updated August 14, 2026) and amazon.com/robots.txt, both retrieved October 3, 2026.
• Seller Central Help, "Selling partner plugin" (help node GAFFEKSK9UR4MGTF, login required); Amazon Selling Partner agentic toolkit (github.com/amzn); Seller Essentials, "Amazon Accelerate 2026 AI tools"; API Evangelist, "Amazon opened Seller Central to agents and kept the storefront closed" (September 24, 2026).
• Amazon v. Perplexity: CNBC, "Amazon wins court order to block Perplexity's AI shopping agent" (March 10, 2026); Cooley, "Ninth Circuit rules on AI agent access to third-party websites under CFAA" (August 6, 2026); Jones Day, "Ninth Circuit vacates CFAA injunction against Perplexity's Comet AI agent" (September 2026); Courthouse News, "No 9th Circuit rehearing in Amazon, Perplexity case".
• The Register, "Amazon shows Meta's Muse AI shopping agent the door" (September 21, 2026).
• OpenAI Help, "ChatGPT agent allowlisting"; Google, "Google-Agent" crawler documentation; Anthropic, "Does Anthropic crawl data from the web, and how can site owners block the crawler?"; HUMAN Security, Perplexity Comet agent profile and Copilot Actions agent profile; CHEQ, "The cyborg session: reversing and detecting the Claude AI agent Chrome extension"; StackFox, "Grok user agent" research.
• Chrome for Developers, chrome.declarativeNetRequest API reference (how an extension appends to the user-agent).