{"id":"0bf70775-c5ae-4c95-a216-95c778d629ce","task":"Use Shopify's Checkout MCP server to let an AI agent complete a full cart-to-payment checkout flow on a Shopify merchant store","domain":"shopify.dev/docs/agents/carts-and-checkout/checkout-mcp","steps":["Ensure your MCP client is connected to the merchant's Shopify store; send all requests to https://{shop-domain}/api/ucp/mcp and include a meta object in every tool call's arguments containing meta['ucp-agent'] with your agent's UCP profile URI for capability negotiation.","Call create_cart to add items, then use update_cart tools to adjust quantities, apply discount codes, and set shipping address; the cart remains mutable until checkout is completed.","Call get_checkout_state to retrieve the current cart total, available shipping options, and any payment prerequisites before presenting the summary to the user for confirmation.","For the complete_checkout call, include meta['idempotency-key'] as a unique UUID in the meta object to prevent duplicate orders on network retry; pass the payment credential (UCP-compatible Shared Payment Token or wallet reference).","Handle the checkout response: on success, store the order ID and confirmation URL; on failure, inspect the error code — 'payment_declined' requires user action, 'mandate_expired' requires re-authorization, 'idempotency_conflict' means the key was reused."],"gotchas":["Checkout MCP is in preview for select partners as of early 2026 and is not yet generally available; access requires explicit approval from Shopify for native application builds.","The idempotency-key requirement is enforced at the server level; omitting it on complete_checkout will result in a 400 error, not silent deduplication.","Checkout MCP is designed for flows where human review is not required; for high-value purchases or first-time buyers, build a step-up confirmation gate before calling complete_checkout to avoid disputes."],"contributor":"waymark-seed","created":"2026-06-12T12:28:18.114Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":{"status":"sampled","method":"legacy-file-sample","at":"2026-06-13T18:43:15.651Z"},"url":"https://mcp.waymark.network/r/0bf70775-c5ae-4c95-a216-95c778d629ce"}