aid: underdog
name: Underdog
description: 'Underdog (legal entity Older is Better, RCS Nantes 918 609 629) is a French direct-to-consumer
  retailer of professionally refurbished large home appliances and televisions — washing machines, fridges,
  dishwashers, tumble dryers, ovens, cookers, freezers, wine cabinets, TVs and Thermomix — reconditioned in
  France and sold at up to 50% below new with a two-year warranty, delivery, installation and old-appliance
  takeback. It is a circular-economy / climate-tech company backed by Serena. Underdog has no developer
  programme and publishes no OpenAPI, but its storefront runs on Shopify and it exposes a genuine, live
  agent-commerce surface on its own domain: an /llms.txt and /agents.md agent instruction document, a
  Universal Commerce Protocol (UCP) merchant profile at /.well-known/ucp, two anonymously-listable remote
  MCP endpoints (a 13-tool UCP commerce server and a 1-tool storefront policy server), an introspectable
  Shopify Storefront GraphQL API, RFC 8414 / RFC 9728 OAuth metadata, and read-only product and collection
  JSON endpoints.'
url: https://raw.githubusercontent.com/api-evangelist/underdog/refs/heads/main/apis.yml
deliveryModel:
  model: saas
  open_source: false
  commercial: true
  callable_host: false
  label: Hosted service · you call their endpoint
  confidence: medium
  source:
  - pricing
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source:
  - security
  generated: '2026-09-02'
  method: derived
image: https://underdog.shop/cdn/shop/files/UND-logo-Noir_1_3878927d-05f3-4209-b1e5-6113f92e6567.png?v=1762513808
x-type: company
x-source: serena-portfolio
x-tier: profiled
x-tier-reason: portfolio-lead
specificationVersion: '0.23'
created: '2026-08-17'
modified: '2026-08-17'
tags:
- Company
- Climate Tech
- Circular Economy
- Refurbished Electronics
- Home Appliances
- Retail
- E-Commerce
- Shopify
- Agentic Commerce
- Universal Commerce Protocol
- MCP
- GraphQL
- France
tags_raw:
- Company
- Climate Tech
- Circular Economy
- Refurbished Electronics
- Home Appliances
- Retail
- Ecommerce
- Shopify
- Agentic Commerce
- Universal Commerce Protocol
- MCP
- GraphQL
- France
apis:
- aid: underdog-ucp-commerce
  name: Underdog UCP Commerce MCP API
  description: 'The Universal Commerce Protocol (UCP) shopping service Underdog serves from its own domain.
    A remote MCP endpoint that answers tools/list anonymously with 13 tools covering catalog search and
    lookup, cart create/read/update/cancel, checkout create/read/update/complete/cancel, and order lookup.
    complete_checkout requires an idempotency-key and buyer approval. Merchant profile and supported
    protocol versions are published at https://underdog.shop/.well-known/ucp.'
  humanURL: https://underdog.shop/agents.md
  baseURL: https://underdog.shop/api/ucp/mcp
  tags:
  - MCP
  - Agentic Commerce
  - Universal Commerce Protocol
  - Checkout
  - Catalog
  properties:
  - type: MCPServer
    url: mcp/underdog-mcp.yml
  - type: ToolCrosswalk
    url: mcp/underdog-tool-crosswalk.yml
  - type: Documentation
    url: https://underdog.shop/agents.md
  - type: Specification
    url: https://ucp.dev/2026-04-08/specification/overview/
- aid: underdog-storefront-graphql
  name: Underdog Storefront GraphQL API
  description: 'The Shopify Storefront GraphQL API as served on underdog.shop. It answers introspection
    anonymously and exposes 424 types, 35 root query fields (products, collections, search, predictiveSearch,
    cart, blog/article, menu, metaobjects, shop, localization) and 41 mutations (cart lifecycle, customer
    accounts, Shop Pay payment request sessions) over Underdog''s own catalogue, priced in EUR for FR.'
  humanURL: https://underdog.shop/llms.txt
  baseURL: https://underdog.shop/api/2026-01/graphql.json
  tags:
  - GraphQL
  - Storefront
  - Catalog
  - Cart
  properties:
  - type: GraphQL
    url: graphql/underdog-storefront.graphql
  - type: DataModel
    url: data-model/underdog-data-model.yml
  - type: ErrorCatalog
    url: errors/underdog-problem-types.yml
- aid: underdog-storefront-mcp
  name: Underdog Storefront Policy MCP API
  description: 'A second remote MCP endpoint on underdog.shop that answers tools/list anonymously with a
    single natural-language tool, search_shop_policies_and_faqs, for questions about the store''s return,
    shipping, warranty and contact policies.'
  humanURL: https://underdog.shop/agents.md
  baseURL: https://underdog.shop/api/mcp
  tags:
  - MCP
  - Support
  - Policies
  properties:
  - type: MCPServer
    url: mcp/underdog-mcp.yml
- aid: underdog-storefront-json
  name: Underdog Storefront JSON Endpoints
  description: 'Read-only, unauthenticated JSON representations of the Underdog catalogue published by the
    Shopify storefront: /products.json, /products/{handle}.json, /collections/{handle}/products.json and
    /search?q=&type=product, plus /sitemap.xml and an agentic-discovery sitemap listing /agents.md.'
  humanURL: https://underdog.shop/llms.txt
  baseURL: https://underdog.shop
  tags:
  - JSON
  - Catalog
  - Product
  tags_raw:
  - JSON
  - Catalog
  - Products
  properties:
  - type: Documentation
    url: https://underdog.shop/llms.txt
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: DomainSecurity
  url: security/underdog-domain-security.yml
- type: Website
  url: https://underdog.shop/
- type: Documentation
  url: https://underdog.shop/agents.md
- type: LLMsTxt
  url: llms/underdog-llms.txt
- type: WellKnown
  url: well-known/underdog-well-known.yml
- type: MCPServer
  url: mcp/underdog-mcp.yml
- type: ToolCrosswalk
  url: mcp/underdog-tool-crosswalk.yml
- type: GraphQL
  url: graphql/underdog-storefront.graphql
- type: Authentication
  url: authentication/underdog-authentication.yml
- type: OAuthScopes
  url: scopes/underdog-scopes.yml
- type: Conformance
  url: conformance/underdog-conformance.yml
- type: Conventions
  url: conventions/underdog-conventions.yml
- type: Idempotency
  url: conventions/underdog-conventions.yml
- type: ErrorCatalog
  url: errors/underdog-problem-types.yml
- type: Lifecycle
  url: lifecycle/underdog-lifecycle.yml
- type: Deprecation
  url: lifecycle/underdog-lifecycle.yml
- type: DataModel
  url: data-model/underdog-data-model.yml
- type: Plans
  url: plans/underdog-plans-pricing.yml
- type: RateLimits
  url: rate-limits/underdog-rate-limits.yml
- type: AgentSkill
  url: skills/_index.yml
- type: GitHubOrganization
  url: https://github.com/underdog-shop
- type: Support
  url: https://underdog.shop/pages/contact
- type: TermsOfService
  url: https://underdog.shop/policies/terms-of-service
- type: PrivacyPolicy
  url: https://underdog.shop/policies/privacy-policy
- type: Login
  url: https://account.underdog.shop/