Agent Briefing

Miyagi Sánchez

Zero-commission marketplace for Mexico — built on the Universal Commerce Protocol (UCP) and MCP-compatible for AI agent commerce.

What is this marketplace?

Miyagi Sánchez is a multi-seller C2C and B2C marketplace serving Mexico. Sellers list products across multiple channels simultaneously: the main marketplace, their own branded domain, an embeddable widget, and a headless API. Commission: 0%.

The platform is designed for AI-native commerce. Buyers can instruct an AI agent to search, negotiate, and complete purchases on their behalf through the UCP API without ever touching a browser UI.

Supported product types

📦Physical goodswith optional shipping

🎓Digital productsinstant delivery via R2

🔁Subscriptionsrecurring Stripe billing

🔧Servicesbookable, quote-based

🏠Rentalsdaily / weekly pricing

Payment methods

Stripecards, OXXO, Link — international

MercadoPagoSPEI, cards, cash — Mexico-native

SPEI transferdirect bank transfer (manual)

API endpoints (UCP)

Base URL: https://miyagisanchez.com

GET/api/ucp/catalog

Search and filter active listings (full-text es-MX, category, price, location, condition, automotive/real-estate filters). Cursor-paginated.

GET/api/ucp/catalog/{id}

Full UCP detail for one listing: trust signals, seller, images, payment methods, checkout URLs.

POST/api/ucp/checkout-session

Get ALL payment options for a listing in one call (instant: MercadoPago, Stripe — with ready URLs; contact-first: SPEI/CLABE, cash, WhatsApp).

POST/api/mp/checkout

Create a MercadoPago Checkout Pro session (cards, OXXO, wallet, meses sin intereses). Returns checkoutUrl.

POST/api/stripe/checkout

Create a Stripe Checkout session for card payments. Returns checkoutUrl.

GET+POST/api/embed/support

Discover a seller support widget by embed key and initiate a guest contribution checkout through the same hosted Stripe/MercadoPago handoff used by the widget.

POST/api/offersauth

Submit a price offer on a listing. Seller has 48h to accept, counter, or decline. Requires an authenticated Miyagi buyer session.

GET/api/ucp/identity/{identifier}

OmniReputation trust score for a buyer by email or Clerk user ID. Returns score, level, and signals (no PII beyond the identifier).

GET/api/ucp/manifest

Machine-readable capability manifest. Fetch first to discover everything this API can do.

GET+POST/api/ucp/mcp

Model Context Protocol server (HTTP / JSON-RPC 2.0). Connect from Claude Desktop, Gemini, or any MCP client for native shopping + seller-config tools.

MCP server setup

Add Miyagi Sánchez as a remote MCP server in Claude Desktop or any MCP-compatible client:

// claude_desktop_config.json
{
  "mcpServers": {
    "miyagi-sanchez": {
      "url": "https://miyagisanchez.com/api/ucp/mcp",
      "transport": "http"
    }
  }
}

Once connected, Claude can browse listings, check seller trust scores, negotiate prices, and complete purchases autonomously on your behalf.

Buyer tools (no auth)

search_listingsget_listingget_checkout_optionscreate_checkoutmake_offerget_shopcheck_availabilitybook_appointmentget_buyer_trustget_support_optionscreate_support_checkout

Seller tools (shop agent token)

get_store_configurationpatch_store_configurationlist_offersrespond_to_offercreate_listinglist_my_listingsupdate_listingset_listing_status

Seller tools read and adjust a shop's own configuration. They require a per-shop token (Authorization: Bearer ms_agent_…) generated in the shop's settings, scoped to that one shop. Payments, custom domain, and Cal.com stay manual.

UCP-enabled use cases

These are live capabilities powered by the Universal Commerce Protocol:

Generic Retail / FashionIdentity Linking (OAuth 2.0) & Embedded Checkout

Pain: Friction in cross-platform authentication, manual input of sizing data, and tedious checkout forms.

Flow: User requests brand updates via AI assistant. AI assistant invokes UCP Identity Linking token to securely access consumer's store profile, loyalty ledger, and physical dimensions. AI executes headless checkout using Google Wallet API without directing user to external web browser.

Home Improvement / General RetailNative Embedded Checkout (Merchant of Record pass-through)

Pain: High cart abandonment rates during multi-step redirection to unknown merchant domains.

Flow: User identifies product within Google Search/Chat interface. UCP surfaces integrated checkout parameters (taxes, localized shipping). User completes transaction instantly inside native interface via Google Wallet. Retailer backend receives structured order payload as direct Merchant of Record.

Electronics / Consumer HardwareOrder Management & Real-Time Webhooks

Pain: Complex, fragmented post-purchase return portals requiring manual customer service intervention.

Flow: User requests a product return natively through AI assistant. AI leverages UCP order webhooks to trigger return authorization event in e-commerce backend. System generates automated return shipping label and registers refund parameters inside database without human intervention.

P2P Marketplace (General / Vinted-Style Mexico)Open Liquidity Network & Medusa Headless Sourcing

Pain: Low mobile app retention and friction for users navigating fragmented P2P listings across regions.

Flow: User requests highly specific second-hand item within Gemini environment. AI queries Medusa database exposed via UCP metadata attributes. Listing displays inline within user's active application. Purchase resolves via universal payment tokens, routing order straight to the tenant's inventory.

P2P Marketplace (Price Negotiation)Model Context Protocol (MCP) & Agent-to-Agent (A2A) Negotiation

Pain: High operational fatigue for casual sellers managing manual, repetitive price haggling ('¿Cuánto lo menos?') over chat apps.

Flow: Buyer's AI agent submits lower price offer to marketplace. Medusa backend AI evaluates offer against programmatic seller constraints (e.g., age of listing, predefined discount bounds). If valid, system automatically updates transaction price and processes immediate automated checkout.

P2P Marketplace (Trust & Safety - Mexico)Verifiable Identity Credentials & Escrow Logic

Pain: High prevalence of identity fraud, ghost accounts, and payment scams ('salvo buen cobro') in the Mexican secondary market.

Flow: Onboarding users link profiles to authenticated global ecosystems via UCP Identity framework. System transmits zero-knowledge trust proofs to Medusa backend. Marketplace displays decentralized trust metrics natively, while Medusa core executes secure payment hold escrow until delivery is verified.

Automotive (Used Cars - Mexico)Asynchronous Pre-Vetting & Escrow Deposits

Pain: Sellers flooded with low-intent inquiries; buyers paralyzed by lack of vehicle history verification (REPUVE) and physical safety fears.

Flow: Buyer's agent queries car listings. Medusa serves UCP metadata containing cryptographically verified government database checks (REPUVE, original invoice validation). Buyer's agent automatically locks a refundable holding deposit into Medusa's escrow via UCP checkout to secure a physical vehicle inspection slot.

Real Estate (Rentals & Sales - Mexico)Pre-Qualified Identity Transmission & Custom Transactional Flows

Pain: High volume of unqualified leads and administrative friction collecting physical identity and income documents over WhatsApp.

Flow: Prospect's AI agent presents a verified UCP token representing identity and income background validation without revealing underlying sensitive raw data. Landlord's system reviews pre-qualification and executes custom UCP action requiring payment for a background check or booking deposit before releasing calendar availability.

Handcrafted & Artisanal Goods (Etsy-Style)Dynamic API Parameter Routing & Conversational Customization

Pain: Inability to calculate complex freight shipping variables dynamically for unique items, paired with manual friction handling custom modifications.

Flow: User inputs custom sizing/color alterations to AI. AI updates product configuration schema and requests validation from Medusa API. Medusa calculates structural material adjustments, fetches real-time regional logistics shipping rates via local carrier APIs, and displays a single, binding UCP checkout price to the user instantly.

External references

ucp.dev — Protocol spec Live marketplace Browse catalog API