Agentzon vs Saleor API + MCP

Agentzon

Public OpenAPI 3.1 description and llms.txt, with a whole-basket checkout that needs no account or key. The buyer pays on a private page, so a person completes each purchase. No status page, security.txt or registered seller address was found on agentzon.co, and 34 of 500 listed items cannot be bought.

Saleor API + MCP

One GraphQL schema with 78 typed error-code enums and 464 marked deprecations. The MCP server can't create checkouts or orders.

Agentzon

1. Search with GET /api/products. Use only items with checkoutAvailable true and a non-null unitAmount, because a null price means unavailable, never free
2. Send every item and quantity in one POST /api/checkout, with a new Idempotency-Key for each purchase attempt and the same key only to retry that basket
3. Show the buyer the product image from /api/products/{id}/image and get their approval before opening the checkout URL
4. Tell the buyer that catalogue prices exclude sales tax, that shipping is U.S. only and that change-of-mind returns exclude hygiene and food items
5. Keep the checkout URL and the orderToken private. A paid status confirms payment, not shipment

Saleor API + MCP

1. Pass the channel slug on product and checkout queries. Prices and availability are per channel
2. Send X-Saleor-API-URL and X-Saleor-Auth-Token on every MCP request, with a token holding MANAGE_PRODUCTS and MANAGE_ORDERS
3. Read the errors array in every mutation payload. A 200 response can still carry a CheckoutErrorCode
4. Keep queries under the 50,000 complexity cap and 100 items a page, and send at most 4 mutations per request
5. The 3.24 changelog removes the old dummy payment plugins, so test checkouts should use a payment app