generated: '2026-08-26'
method: probed
source: >-
  Derived from the live tools/list responses at https://relesium.com/api/ucp/mcp and
  https://www.lifesfirstnaturals.com/api/ucp/mcp, the UCP merchant profiles at /.well-known/ucp,
  and the agent instructions each store publishes at /llms.txt (all HTTP 200 on 2026-08-26).
scope_note: >-
  These conventions describe the UCP-over-MCP commerce surface on the two PanTheryx brand
  storefronts. They are platform conventions supplied by Shopify, not house style authored by
  PanTheryx, which publishes no API documentation of its own.
transport:
  protocol: JSON-RPC 2.0 over MCP
  content_type: application/json
  accept: application/json, text/event-stream
  method_discovery: tools/list
auth_style:
  discovery: anonymous - no credential required for tools/list, catalog reads, or /.well-known/ucp
  customer_context: OAuth 2.0 / OpenID Connect (Shopify customer accounts) - see authentication/
  payment: >-
    a payment instrument is supplied on the checkout object; handlers are com.google.pay,
    dev.shopify.card and dev.shopify.shop_pay
identifiers:
  style: Shopify global IDs
  format: 'gid://shopify/<Type>/<id>'
  example_documented: 'gid://shopify/Checkout/abc123'
  source: the id parameter description on get_checkout and update_checkout
money:
  representation: integer minor units paired with an ISO 4217 currency code
  shape: '{"amount": 2500, "currency": "USD"} is $25.00'
  agent_rule: >-
    convert to major units before quoting a price to a buyer - divide by 100 for two-decimal
    currencies; zero-decimal currencies such as JPY are already whole units
  source: stated in every tool description in tools/list
agent_profile:
  required: true
  field: meta.ucp-agent.profile
  note: >-
    Every tool declares meta as a required input carrying a ucp-agent.profile URI for UCP agent
    profile discovery. An agent that omits it will fail schema validation.
buyer_context:
  documented_fields:
  - context.address_country
  - context.currency
  purpose: accurate pricing and availability
  source: the "Use buyer context" rule in each store's llms.txt
pagination:
  documented: false
  note: >-
    No pagination convention is documented for search_catalog in the tool descriptions or in
    llms.txt. Not asserted.
versioning:
  style: dated protocol versions negotiated through the UCP merchant profile
  current: '2026-04-08'
  supported:
  - '2026-01-23'
  - '2026-04-08'
  discovery: GET /.well-known/ucp
error_envelope:
  style: JSON-RPC 2.0 error objects
  documented_catalog: false
  note: >-
    No error-code reference is published. complete_checkout is documented only as returning
    "any errors encountered". No RFC 9457 problem+json surface exists, so errors/ is not written.
rate_limit_signaling:
  documented: true
  detail: >-
    "The MCP endpoint is rate-limited per IP. Back off on 429 responses." - published in each
    store's llms.txt. No numeric limit and no response headers are named. See
    rate-limits/pantheryx-rate-limits.yml.
idempotency:
  supported: unknown
  grade: na
  note: >-
    No idempotency key, header, or retry-safety statement appears in any tool inputSchema, in the
    UCP merchant profile, or in either store's llms.txt. The pipeline does not assert idempotency
    that the contract does not state, and no Idempotency pointer is emitted for this provider.
dry_run_mode:
  supported: false
  grade: na
  note: >-
    No test mode, sandbox store, simulation flag or dry-run parameter is published. A cart or
    checkout created against these endpoints is a real cart against the live storefront.
reversibility:
  grade: documented
  rationale: >-
    Reversal operations exist and are named in the live contract, but no store, policy page or tool
    description states a window inside which they work - so this is documented, not verified. No
    window is asserted here, because inventing one could cost a buyer real money.
  surfaces:
  - write_operation: create_cart
    tool: create_cart
    reversal: cancel_cart
    window: null
    window_source: null
    evidence: >-
      cancel_cart is present in tools/list on both storefronts with the description "Cancels a
      cart."
  - write_operation: create_checkout
    tool: create_checkout
    reversal: cancel_checkout
    window: null
    window_source: null
    evidence: >-
      cancel_checkout is present in tools/list on both storefronts with the description "Cancels a
      checkout." No documentation states whether it remains available after complete_checkout.
  - write_operation: complete_checkout
    tool: complete_checkout
    reversal: none-in-contract
    window: null
    window_source: null
    evidence: >-
      There is no refund, void or reverse tool in tools/list. Once complete_checkout succeeds, the
      only published reversal path is out-of-band: the Relesium refund policy at
      https://relesium.com/policies/refund-policy (HTTP 200) says only "If you do need to return an
      order, we're happy to help. Just email us at info@relesium.com and we'll take you through the
      return process." It states no return window, no eligibility conditions and no cancellation
      procedure.
  agent_guidance: >-
    An agent can safely abandon a cart or an uncompleted checkout through the API. It cannot undo a
    completed order through the API at all, and it cannot tell a buyer how long they have to return
    one, because the merchant does not say.
cross_links:
  authentication: authentication/pantheryx-authentication.yml
  scopes: scopes/pantheryx-scopes.yml
  rate_limits: rate-limits/pantheryx-rate-limits.yml
  lifecycle: lifecycle/pantheryx-lifecycle.yml
  conformance: conformance/pantheryx-conformance.yml
  mcp:
  - mcp/pantheryx-relesium-mcp.yml
  - mcp/pantheryx-lifes-first-naturals-mcp.yml