generated: '2026-08-23'
method: derived
source: mcp/l-nutra-prolonlife-ucp-tools-list.json
description: >-
  Entity-relationship graph derived from the JSON Schema 2020-12 input schemas of the thirteen UCP
  tools live on https://prolonlife.com/api/ucp/mcp. There is no OpenAPI and no components.schemas
  block, so every entity and field below was read out of a tool's own inputSchema. Identifiers on
  this surface are Shopify global IDs (gid://shopify/<Type>/<n>), which is itself the id convention.
id_scheme:
  format: 'gid://shopify/<Type>/<numeric-id>'
  examples_from_spec:
  - 'gid://shopify/Order/123'
  note: Confirmed in the get_order id description; the same GID form governs product and variant ids.
entities:
- name: Cart
  source_tools: [create_cart, get_cart, update_cart, cancel_cart]
  fields: [id, line_items, buyer, context]
  relationships:
  - has_many: LineItem
    via: line_items
  - has_one: Buyer
    via: buyer
- name: LineItem
  source_tools: [create_cart, update_cart, create_checkout, update_checkout]
  fields: [id, quantity, item]
  required: [item, quantity]
  relationships:
  - belongs_to: ProductVariant
    via: item.id
- name: Checkout
  source_tools: [create_checkout, get_checkout, update_checkout, complete_checkout, cancel_checkout]
  fields: [id, line_items, buyer, payment, fulfillment, discounts, totals, context]
  relationships:
  - has_many: LineItem
    via: line_items
  - has_one: Buyer
    via: buyer
  - has_many: PaymentInstrument
    via: payment.instruments
  - has_one: Order
    via: order id returned by complete_checkout
- name: PaymentInstrument
  source_tools: [create_checkout, update_checkout]
  fields: [id, handler_id, type, billing_address]
  required: [id, handler_id, type]
  relationships:
  - belongs_to: PaymentHandler
    via: handler_id
  note: >-
    type is 'card' for credit/debit and 'token' for wallet payments (Google Pay, Apple Pay).
- name: PaymentHandler
  source: /.well-known/ucp payment_handlers
  fields: [id, version, spec, schema, config]
  instances:
  - id: gpay
    handler: com.google.pay
    merchant_name: Prolon Life
    merchant_origin: prolonlife.com
    card_networks: [VISA, MASTERCARD, AMEX, DISCOVER]
- name: Buyer
  source_tools: [create_cart, create_checkout]
  fields: [email, phone_number]
- name: Order
  source_tools: [get_order, complete_checkout]
  fields: [id]
  relationships:
  - belongs_to: Checkout
    via: the checkout that completed it
- name: Product
  source_tools: [search_catalog, lookup_catalog, get_product]
  fields: [id, variants, pricing, availability]
  relationships:
  - has_many: ProductVariant
    via: variants
- name: ProductVariant
  source_tools: [lookup_catalog, get_product]
  fields: [id, price, availability]
  relationships:
  - belongs_to: Product
- name: BuyerContext
  source_tools: [search_catalog, create_cart, create_checkout]
  fields: [address_country, address_region, postal_code, language, currency, intent]
  note: >-
    address_country is ISO 3166-1 alpha-2, language is IETF BCP 47, currency is ISO 4217.
money:
  representation: '{ amount: <integer minor units>, currency: <ISO 4217> }'
  note: Stated in every tool description; see conventions/l-nutra-conventions.yml.
gaps:
- Response schemas are not published — MCP tools/list carries inputSchema only, so field-level
  detail on Order, Product and Checkout responses is inferred from tool prose, not from a schema.
- Subscription is a real entity in the business (the refund policy describes subscription renewal
  and cancellation) but no MCP tool exposes it.