{ "schema": "varexis-public-evidence-record/0.3", "generated_at_utc": "2026-10-13T23:52:59.204Z", "record_id": "VXI-EXT-TOOL-TRUST-SHOPIFY-CART-01-v1", "record_kind": "external_reference", "title": "Shopify Cart MCP: Cart changes and purchase authority", "system": "Shopify UCP Cart MCP", "evidence_family": "agent_tool_trust_review", "index_status": "PUBLIC_SAFE_SOURCE_REVIEW", "evidence_state": "PRIMARY_DOCUMENTATION_REVIEW_ONLY", "canonical_question": "Can a shopping agent prepare a Shopify cart without committing the buyer to payment?", "near_questions": [ "Can Shopify Cart MCP prepare a cart without payment?", "Does a Shopify cart total prove a completed purchase?", "Does Shopify update_cart replace the whole cart?", "What changed for older Shopify Storefront MCP cart tools?", "Does Shopify Cart MCP require an agent profile?", "Is Checkout MCP authentication separate from Cart MCP?", "What happens if an agent omits items when replacing a cart?", "Which merchant receives the Shopify cart request?", "Should an agent treat estimated Shopify totals as final prices?", "Can an agent cancel a pre-checkout Shopify cart?", "What evidence separates cart authority from purchase authority?", "When should a Shopify MCP migration review be refreshed?" ], "supported_claims": [ { "claim": "Shopify separates Cart MCP from Checkout MCP. Cart tools can create, read, replace and cancel a pre-checkout cart using unauthenticated requests with agent-profile metadata. Checkout has a separate authentication boundary. Older Storefront cart tools were removed; a cart or estimated total is not proof of payment.", "reliance": "DOCUMENTED_CAPABILITY_ONLY" } ], "not_demonstrated_claims": [ "Verified buyer configuration or effective access rights", "Independent execution, completeness or security testing", "Vendor certification, legal compliance or guaranteed suitability" ], "public_summary": "Shopify separates Cart MCP from Checkout MCP. Cart tools can create, read, replace and cancel a pre-checkout cart using unauthenticated requests with agent-profile metadata. Checkout has a separate authentication boundary. Older Storefront cart tools were removed; a cart or estimated total is not proof of payment.", "related_record_ids": [ "VXI-EXT-TOOL-TRUST-POSTMAN-01-v1", "VXI-EXT-TOOL-TRUST-ZAPIER-01-v1", "VXI-EXT-TOOL-TRUST-DOCKER-01-v1" ], "source_review": { "source_type": "official_external_documentation", "source_title": "Shopify UCP Cart MCP pre-purchase capabilities", "source_url": "https://shopify.dev/docs/agents/carts-and-checkout/cart-mcp", "checked_on": "2026-10-14", "candidate_record_id": "VXI-EXT-TOOL-TRUST-SHOPIFY-CART-01-v1", "candidate_record_sha256": "78a366dd048e81a9f36603085b4ee23f9f4916ec1f9f1c17d53fc3bb3cb913f8", "method": "Primary documentation reviewed for the published bounded statement.", "deployment_tested_by_varexis": false, "revalidation": "The delivered snapshot preserves the review date shown. Recheck current primary documentation and deployment context before relying on present applicability; payment does not trigger fresh research." }, "answer_policy": { "classification": "DOCUMENTED_WITH_DEPLOYMENT_BOUNDARY", "bounded_answer": "Shopify separates Cart MCP from Checkout MCP. Cart tools can create, read, replace and cancel a pre-checkout cart using unauthenticated requests with agent-profile metadata. Checkout has a separate authentication boundary. Older Storefront cart tools were removed; a cart or estimated total is not proof of payment.", "required_buyer_context": "Merchant endpoint, negotiated UCP capability, agent profile, cart identity and buyer purchase authority.", "missing_evidence": "A broader claim needs evidence matching the intended use. Payment does not upgrade the evidence state." }, "private_boundary": "Raw logs, thresholds, private paths, source code, protected mechanisms and reconstruction-level details are excluded from public and paid delivery.", "trust_profile": { "schema": "varexis-agent-tool-trust/1", "identity": { "tool": "Shopify UCP Cart MCP", "variant": "Merchant Cart MCP over UCP; separate from checkout and deprecated Storefront cart tools" }, "review_status": "documentation_review_only", "checked_on": "2026-10-14", "version_scope": "Dated rolling documentation snapshot; no installed or hosted runtime version independently verified.", "plan_scope": "Buyer plan, entitlement and effective configuration are not verified.", "findings": [ { "field": "operator", "label": "Publisher and operator", "status": "documented", "statement": "Shopify documents the service; calls target the selected merchant storefront.", "source_ids": [ "shopify-main", "shopify-migration" ] }, { "field": "purpose", "label": "Purpose", "status": "documented", "statement": "Cart MCP supports pre-purchase cart preparation before conversion to checkout.", "source_ids": [ "shopify-main", "shopify-migration" ] }, { "field": "reads", "label": "Read capability", "status": "documented", "statement": "The get-cart operation returns the current cart and estimated totals.", "source_ids": [ "shopify-main", "shopify-migration" ] }, { "field": "writes", "label": "Write capability", "status": "documented", "statement": "Create, update and cancel operations change cart state; update replaces the cart contents.", "source_ids": [ "shopify-main", "shopify-migration" ] }, { "field": "auth", "label": "Authentication", "status": "documented", "statement": "Cart calls accept unauthenticated requests with required agent-profile metadata; Checkout MCP requires separate authentication or signing.", "source_ids": [ "shopify-main", "shopify-migration" ] }, { "field": "permissions", "label": "Permission surface", "status": "documented", "statement": "Cart and checkout are separate capabilities with distinct access and rate limits.", "source_ids": [ "shopify-main", "shopify-migration" ] }, { "field": "egress", "label": "Data leaving the environment", "status": "review_inference", "statement": "Line items and any supplied buyer context are sent to the merchant service and returned through the client.", "source_ids": [ "shopify-main", "shopify-migration" ] }, { "field": "failures", "label": "Failure modes to consider", "status": "review_inference", "statement": "A partial replacement can remove intended items; an old Storefront endpoint or stale cart total can mislead a buying workflow.", "source_ids": [ "shopify-main", "shopify-migration" ] }, { "field": "unknown", "label": "Unknowns and applicability", "status": "unknown", "statement": "Merchant support, negotiated version, final pricing and buyer payment authority are unverified.", "source_ids": [] }, { "field": "gate", "label": "Suggested refusal or clarification condition", "status": "varexis_review_policy", "statement": "Keep cart preparation separate from purchase approval and verify the current cart before requesting checkout.", "source_ids": [] } ], "evidence_sources": [ { "source_id": "shopify-main", "url": "https://shopify.dev/docs/agents/carts-and-checkout/cart-mcp", "final_url": "https://shopify.dev/docs/agents/carts-and-checkout/cart-mcp", "title": "Shopify UCP Cart MCP pre-purchase capabilities", "checked_on": "2026-10-14", "sha256": "e2f596e836ef1c176b44a50a413e85f8b760091e1935efe0b75d96e1302a74dc", "bytes": 501114 }, { "source_id": "shopify-migration", "url": "https://shopify.dev/docs/apps/build/storefront-mcp", "final_url": "https://shopify.dev/docs/apps/build/storefront-mcp", "title": "Shopify Storefront MCP migration", "checked_on": "2026-10-14", "sha256": "c20749ed793bc3d3a10367830dace10af8f96e39f544154613ffdecd9671b696", "bytes": 439758 } ], "observed_tool_execution": false, "policy_basis": "Suggested VAREXIS review gates; apply the buyer's authorized task and policy. These conditions do not execute or enforce controls.", "commercial_reliance_boundary": "A source-linked review aid, not a vendor certification, security clearance or deployment assessment. Unknown does not mean false or unsafe.", "paid_value": { "decision_context": "Preserve the protocol and buyer-authority boundary behind pre-purchase cart preparation.", "free": "Complete review, practical questions, sources and limitations; may be saved locally.", "single_request": "Existing server-saved version-bound route snapshot for later authenticated retrieval.", "evidence_receipt": "The same snapshot plus the existing unsigned delivery receipt.", "excluded": [ "Fresh vendor research", "Continuous monitoring or change alerts", "Testing the buyer configuration", "Private evidence or vendor certification" ], "integrity": "Hashes identify content versions; they do not prove truth or provide a signature." }, "revalidation": { "trigger": "Recheck when permissions, deployment, authentication, source guidance or intended use changes; a purchase does not trigger revalidation.", "specific_watch": "Recheck merchant capabilities, cart replacement behavior and checkout authentication." }, "change_history": [ { "version": 1, "date": "2026-10-14", "change": "Initial documentation review; no earlier vendor assessment claimed." } ] }, "paid_access_note": "The full published answer and boundaries are free. Paid access saves the selected route and source versions, with an unsigned receipt when purchased. Preview coverage before paying. Fresh research, bespoke assessment and protected evidence are excluded.", "service_route": { "request_guide": "/varexis-index/request.html", "request_workflow": "/varexis-index/request-workflow.json", "service_id": "single_request", "service_routes_url": "/varexis-index/service-routes.json", "payment_required": true, "availability_endpoint": "/api/index/capabilities", "operational_status": "AUTOMATIC_SERVICE_CAPABILITIES_GATED", "checkout_url": "/index-access" }, "authority_boundary": "VAREXIS-INDEX informs evidence reliance. It does not provide advice, certification, deployment authority, security assurance, production approval, or guarantee.", "human_page": "/varexis-index/catalog.html#shopify-cart-mcp-purchase-boundary-trust", "machine_readable_record": "/varexis-index/records/shopify-cart-mcp-purchase-boundary-trust.json" }