UCP Implementation Deck

Wix UCP TPA - Complete Protocol Implementation

Slide 1: What We Built

Full UCP Protocol Implementation on Wix

Component	Status
Discovery	✅ `/.well-known/ucp`
Catalog & Cart	✅ Full CRUD
Checkout	✅ Create/Update/Complete
Payment Handlers	✅ Mint & Validate
Orders & Fulfillment	✅ With Webhooks
Identity & Consent	✅ GDPR Compliant
Protocol Bindings	✅ MCP + A2A

176 tests passing | 14 phases complete

Slide 2: UCP Playground Alignment

Matches all 8 steps from ucp.dev/playground

Step	Implementation
1. Platform Profile	Capability discovery
2. Discovery	`/.well-known/ucp`
3. Capability Negotiation	10 capabilities
4. Create Checkout	`POST /ucp/checkout`
5. Update Checkout	`PATCH /ucp/checkout/:id`
6. Mint Instrument	`POST /checkout/:id/mint`
7. Complete Checkout	`POST /checkout/:id/complete`
8. Webhooks	Fulfillment events

Slide 3: Capabilities

{
  "capabilities": [
    "catalog_search",
    "product_details", 
    "cart_management",
    "checkout",
    "orders",
    "fulfillment",
    "discounts",
    "payment_handlers",
    "server_checkout",
    "identity_linking"
  ]
}

Payment Handlers: com.wix.checkout.v1, com.ucp.sandbox

Slide 4: Core Commerce (Phases 1-6)

Feature	Endpoint
Browse Products	`GET /ucp/products`
Product Details	`GET /ucp/products/:id`
Create Cart	`POST /ucp/cart`
Add to Cart	`POST /ucp/cart/items`
Update Item	`PUT /ucp/cart/items/:id`
Create Checkout	`POST /ucp/checkout`

Powered by Wix SDK with OAuth + Headless mode

Slide 5: Orders & Fulfillment (Phases 7, 9)

Orders API

Endpoint	Action
`GET /ucp/orders`	List with filters
`GET /ucp/orders/:id`	Get details
`GET /ucp/orders/:id/fulfillments`	Track shipments

Webhook Events

order.fulfilled
shipment.in_transit
shipment.delivered
tracking.updated

Slide 6: Schema Validation (Phase 8)

Zod-powered request validation

router.post('/ucp/cart', 
  validate(UCPCreateCartRequestSchema),
  handler
);

Standardized Error Response:

{
  "error": "Validation Error",
  "code": "VALIDATION_ERROR",
  "details": [
    { "field": "items[0].quantity", "message": "Required" }
  ]
}

Slide 7: Discounts (Phase 10)

Endpoint	Action
`POST /checkout/:id/coupons`	Apply coupon
`DELETE /checkout/:id/coupons`	Remove
`GET /checkout/:id/discounts`	View applied

Response includes:

Discount breakdown
Updated totals
Coupon validation

Slide 8: Payment Handlers (Phase 11)

Flow

Discovery → Select Handler → Mint Instrument → Validate → Use

Endpoints

Action	Endpoint
List Handlers	`GET /ucp/payment-handlers`
Mint	`POST /checkout/:id/mint`
Validate	`POST /instruments/:id/validate`

Sandbox Test Cards

4242... = Success
4000...0002 = Decline

Slide 9: Server-Side Checkout (Phase 12)

Complete purchase via API - no redirects

POST /ucp/checkout/:id/complete
{
  "instrumentId": "instr_abc",
  "billingAddress": {...},
  "shippingAddress": {...},
  "idempotencyKey": "unique-123"
}

Returns: Order ID, transaction details, totals

✅ Idempotent | ✅ One-time instrument use | ✅ Secure

Slide 10: MCP Binding (Phase 13)

Expose UCP as LLM tools

Tool	Description
`ucp_discover`	Get capabilities
`ucp_search_products`	Search catalog
`ucp_create_cart`	Start cart
`ucp_complete_checkout`	Purchase

POST /mcp/call
{ "name": "ucp_search_products", "arguments": {"query": "drinks"} }

Slide 11: A2A Binding (Phase 13)

Agent-to-Agent transaction handoff

Agent A                    UCP                    Agent B
   │── POST /a2a/handoff ──▶│                        │
   │◀── handoffId + token ──│                        │
   │                        │◀── accept + complete ──│
   │◀── webhook ────────────│                        │

Use case: Transfer shopping session between agents

Slide 12: Identity & Consent (Phase 14)

Identity Linking

POST /ucp/identity/link
{ "primaryId": "user@email.com", "platform": "alexa", "userId": "amzn1..." }

Consent Management

Marketing | Analytics | Personalization
Grant, query, withdraw consent

GDPR

GET /gdpr/export/:id - Data export
POST /gdpr/delete - Right to erasure

Slide 13: Architecture

┌─────────────────────────────────────────┐
│           AI Agents / LLMs              │
└──────────────────┬──────────────────────┘
                   │ MCP / A2A / REST
┌──────────────────▼──────────────────────┐
│            UCP API Layer                │
│  Discovery │ Cart │ Checkout │ Orders   │
└──────────────────┬──────────────────────┘
                   │ Wix SDK
┌──────────────────▼──────────────────────┐
│         Wix eCommerce Platform          │
│   Products │ Cart │ Checkout │ Payments │
└─────────────────────────────────────────┘

Slide 14: Test Coverage

Phase	Tests	Coverage
7-10	45	Orders, Validation, Fulfillment, Discounts
11	35	Payment Handlers
12	20	Server Checkout
13	40	MCP + A2A
14	36	Identity + Consent
Total	176	100%

All tests passing ✅

Slide 15: Live Demo

Production: https://wix-ucp-tpa.onrender.com

Interface	URL
Discovery	`/.well-known/ucp`
AI Chat	`/test/llm`
Full Test UI	`/test/full`
Storefront	`/test/storefront`

Slide 16: Summary

✅ Complete UCP Implementation

10 Capabilities fully implemented
All 8 Playground steps covered
2 Protocol Bindings (MCP + A2A)
176 Tests passing
Production deployed on Render

Powered By

Wix eCommerce SDK
Express.js + TypeScript
Zod validation

UCP Spec Version: 1.0 | Status: 100% Complete 🎉