AutoShop · seller authority for agentic commerce

The agent handles routine orders.
The seller keeps authority.

AutoShop lets a seller give a browser agent a live numerical mandate. Orders inside it can proceed; exceptions stop for exact, visible human approval; every successful decision leaves a receipt. The tiny synthetic marketplace is the deterministic test harness that makes this seller boundary easy to inspect.

6 units requested → mandate allows 5 → APPROVAL_REQUIRED → seller approves one exact action → immutable receipt

Open the seller control plane Generate a buyer order Read the source on GitHub
  • 4 authenticated seller tools
  • Live, versioned numerical mandate
  • Out-of-mandate actions stop
  • Exact human approval before commit
  • Synthetic only · no payments
Schematic: seeded parts flow through a green agent node, then across an amber dashed boundary to a human approval switch that issues a receipt.
fig. 1 — the authority circuitamber line = human decides

How it works

One seller decision, proved end to end

The buyer portal creates a reproducible workload. The seller control plane is the product: the agent acts inside the merchant's mandate, while every exception remains visible and human-controlled.

Seller control plane

Open seller portal
  1. 01AuthenticateSeller tools stay hidden until sign-in.Gate
  2. 02Enforce mandateOrders inside the numerical mandate can be accepted by the agent.Agent scope
  3. 03Approve exceptionAnything outside it waits for one explicit, visible approval.Human decision

Deterministic workload

Generate buyer order
  1. 01BrowseThe agent inspects seeded stock and prices.Agent scope
  2. 02Choose scopeAsk or Auto decides whether it may change the cart.Agent scope
  3. 03ConfirmYou review the exact cart and authorize the order once.Human decision

What makes it trustworthy

Small surface. Sharp edges.

Every feature exists to make the authority boundary legible within seconds — to a judge, a buyer, a seller, or the agent itself.

Role-scoped WebMCP tools

Three buyer tools and four seller tools, each with a strict input schema. Seller tools are registered only after sign-in and removed on logout, expiry, or leaving the page.

Ask or Auto scope

Ask keeps cart changes human-driven. Auto lets the agent browse and change the cart. Neither mode can submit until the buyer visibly confirms the exact order.

Visible buyer confirmation

Confirmation mints a one-time token bound to the exact cart version. Change the cart and authorization is cancelled; no order can be submitted until the buyer confirms again.

Numerical seller mandate

Items per order, total, discount, and minimum remaining stock are versioned limits. Orders that fit are eligible for agent acceptance; the rest are not.

Exceptional approval, once

An out-of-mandate action becomes a pending item. A human reviews the exact action ID, ticks the confirmation, and commits it exactly once with an idempotency key.

Immutable receipts, honest data

Every commit changes synthetic stock and issues a receipt that cannot be edited. Buyer-authored text is rendered as text, never as markup, and never authorizes anything.

Tool contracts

Seven tools. Nothing hidden.

What an agent connected through WebMCP can see on each page. Read-only tools never change state; mutating tools are marked and bounded.

/buyer3 tools · always registered

browse_products
Find up to 8 parts by an optional 80-character query. Read-only.
manage_cart
Add, set, or remove one bounded quantity. Changes cart state only.
submit_order
Submit one visibly confirmed order; private authorization never enters the tool input.

Seller tools are unavailable on this page.

/seller4 tools · after sign-in only

get_mandate
Read the current numerical mandate. Read-only.
list_orders
Read up to 5 order summaries. Buyer content is flagged untrusted.
accept_order
Accept a bounded quantity with an idempotency key — or get APPROVAL_REQUIRED.
commit_action
Commit one visibly approved action; private authorization never enters the tool input.

Removed on logout, session expiry, or leaving the page.

Seeded catalogue

Three parts, deterministic stock

The demo ships with a small seeded inventory so every run starts from the same numbers. The seller portal can reset it at any time.

Technical drawing of a processor package 10 in stock

Ryzen 5 7600

$189.00 cpu-1

Technical drawing of a memory module 12 in stock

16GB DDR5 Kit

$49.00 ram-1

Technical drawing of an M.2 solid-state drive 8 in stock

1TB NVMe SSD

$69.00 ssd-1

Try it

Pick a side of the counter

Open a portal in a WebMCP-capable browser to let an agent work with you, or drive everything by hand — the boundaries hold either way.

Seller control plane · the product

Sign in, tune the mandate, approve the exceptions.

Uses the privately supplied demo credential. The credential is never embedded in the page or repository.

Sign in as seller

Buyer portal · workload generator

Build a cart, choose the agent's scope, confirm once.

No account needed. A private browser cookie scopes server-side demo state; the one-time confirmation token stays only in page memory.

Generate an order