UCP Checker
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UCP status report

assay.agentdiet.dev

Verified

assay.agentdiet.dev publishes a valid UCP profile. That is what it declares. An observed agent run shows how far an agent actually gets.

ShopwareREST, Embedded, MCPHTTP 200 in 74 msrelease 2026-08-25

UCP Score 100/100 grade A · ready for UCP agents To fix 0 nothing to fix
Passed 16 checks
Checked 21 Oct 11:46 UTC · public requests

Findings

16 passed · 0 to fix
Discovery
OK
HTTPS
https
Profile URL uses https://
https
OK
UCP profile reachable
/.well-known/ucp
HTTP 200
/.well-known/ucp
OK
AI bot access
robots.txt
robots.txt allows /.well-known/ucp
robots.txt
UCP profile
OK
Profile passes schema validation
ucp
No structural errors
ucp
OK
Protocol version present and well-formed
ucp.version
Version: 2026-08-25
ucp.version
OK
Public keys published
keys
Keys published at the top level
keys
OK
No validation warnings
ucp
No outstanding validation issues
ucp
Services
OK
Capabilities declared
capabilities
6 of 6 capability families detected: Checkout, Identity Linking, Cart Management, Order Management, Payment Token Exchange, Catalog. A family counts once however many namespaces or extensions declare it.
capabilities
OK
Checkout capability
shopping.checkout
dev.ucp.shopping.checkout detected
shopping.checkout
OK
Transports declared
services
REST, Embedded, MCP
services
OK
Payment handlers
payment_handlers
2 handlers registered
payment_handlers
Outside UCP
OK
llms.txt
/llms.txt
Found at /llms.txt
/llms.txt
OK
sitemap.xml
/sitemap.xml
Found at /sitemap.xml
/sitemap.xml
OK
Open Graph tags
og: meta
og:title and og:type/url present
og: meta
OK
Organization schema (JSON-LD)
JSON-LD
Organization-typed JSON-LD detected
JSON-LD
OK
Mobile viewport meta
meta viewport
<meta name="viewport"> present
meta viewport
Check trace

How assay.agentdiet.dev answered our check

The five ways an agent can reach this store, what each one met, and every request we made.

2 of 5 open
4 requests · 74 ms at the store · public requests only
  1. 01Hosting ↗
    Finding the profile
    Open
  2. 02Identity Linking ↗
    Acting for the buyer
    Offered
  3. 03Embedded ↗
    In the buyer's browser
    Declared
  4. 04Services ↗
    Calling its services
    Declared
  5. 05continue_url ↗
    Sending the buyer to the website
    Not declared
UCP Checkerpublic requests
  • 2 requestsFinding the profile/.well-known/ucp · 200
  • read from profileActing for the buyerdeclared
  • not calledIn the buyer's browserEmbedded · declared
  • not calledCalling its servicesREST, MCP · declared · 13 tools
  • read from profileSending to the websitenot declared
  • 2 requestsOutside UCPhomepage · /llms.txt
Open
01 · Finding the profile2 requests
Served at /.well-known/ucp with 200 OK, 7.4 KB. robots.txt allows /.well-known/ucp.
Offered
02 · Acting for the buyerread from profile
Identity linking is declared.
Declared
03 · In the buyer's browsernot called
Declared. We don't call it, so whether it works shows only in an agent run.
Declared
04 · Calling its servicesnot called
The REST service is declared; not called by this check. The MCP service is declared; not called by this check.
Not declared
05 · Sending the buyer to the websiteread from profile
No permalink declared. Whether error replies carry a continue_url shows only in an agent run.
  1. 01 PROFILEGET /.well-known/ucp → 200, 7.4 KB of JSON74 ms
  2. 01 PROFILEGET /robots.txt → allows /.well-known/ucp–
  3. 01 PROFILEValid against the 2026-08-25 schema; keys publishedlocal
  4. 03 NOTEEmbedded service declared; not called by this check–
  5. OUTSIDE UCPGET / → 200, Organization schema found–
  6. OUTSIDE UCPGET /llms.txt → 200, 2.2 KB–

MCP tools

13 listed · 13 of 13 the spec expects

The tools assay.agentdiet.dev's MCP service listed when we asked (tools/list), grouped by the capability in its profile that calls for them.

Catalog searchdev.ucp.shopping.catalog.search
search_catalog
Catalog lookupdev.ucp.shopping.catalog.lookup
lookup_catalogget_product
Cartdev.ucp.shopping.cart
create_cartget_cartupdate_cartcancel_cart
Checkoutdev.ucp.shopping.checkout
create_checkoutget_checkoutupdate_checkoutcomplete_checkoutcancel_checkout
Orderdev.ucp.shopping.order
get_order

Capabilities

12 declared, all at 2026-08-25
Cart shopping.cart
Order Management shopping.order
Checkout shopping.checkout
Discountextension shopping.discount
Fulfillmentextension shopping.fulfillment
Location Lookup common.location.lookup
Location Search common.location.search
Buyer Consentextension shopping.buyer_consent
Identity Linking common.identity_linking
Catalog Lookup shopping.catalog.lookup
Catalog Search shopping.catalog.search
AP2 Mandateextension common.payment.ap2_mandate

Payment handlers

2 declared
Session Credit stripe-mpp-pass
Delegate Checkout x402-base-usdc
UCP profile as served 9.1 KB · 209 lines 
{
    "ucp": {
        "version": "2026-08-25",
        "services": {
            "dev.ucp.common": [
                {
                    "spec": "https://ucp.dev/2026-08-25/specification/overview",
                    "schema": "https://ucp.dev/2026-08-25/services/common/rest.openapi.json",
                    "version": "2026-08-25",
                    "endpoint": "https://assay.agentdiet.dev/ucp",
                    "transport": "rest"
                },
                {
                    "spec": "https://ucp.dev/2026-08-25/specification/overview",
                    "schema": "https://ucp.dev/2026-08-25/services/shopping/embedded.openrpc.json",
                    "version": "2026-08-25",
                    "endpoint": "https://assay.agentdiet.dev/ucp/embedded-checkout",
                    "transport": "embedded"
                },
                {
                    "spec": "https://ucp.dev/2026-08-25/specification/overview",
                    "schema": "https://ucp.dev/2026-08-25/services/common/mcp.openrpc.json",
                    "version": "2026-08-25",
                    "endpoint": "https://assay.agentdiet.dev/ucp/mcp",
                    "transport": "mcp"
                }
            ],
            "dev.ucp.shopping": [
                {
                    "spec": "https://ucp.dev/2026-08-25/specification/overview",
                    "schema": "https://ucp.dev/2026-08-25/services/shopping/rest.openapi.json",
                    "version": "2026-08-25",
                    "endpoint": "https://assay.agentdiet.dev/ucp",
                    "transport": "rest"
                },
                {
                    "spec": "https://ucp.dev/2026-08-25/specification/overview",
                    "schema": "https://ucp.dev/2026-08-25/services/shopping/embedded.openrpc.json",
                    "version": "2026-08-25",
                    "endpoint": "https://assay.agentdiet.dev/ucp/embedded-checkout",
                    "transport": "embedded"
                },
                {
                    "spec": "https://ucp.dev/2026-08-25/specification/overview",
                    "schema": "https://ucp.dev/2026-08-25/services/shopping/mcp.openrpc.json",
                    "version": "2026-08-25",
                    "endpoint": "https://assay.agentdiet.dev/ucp/mcp",
                    "transport": "mcp"
                }
            ]
        },
        "capabilities": {
            "dev.ucp.shopping.cart": [
                {
                    "spec": "https://ucp.dev/2026-08-25/specification/shopping/cart",
                    "schema": "https://ucp.dev/2026-08-25/schemas/shopping/cart.json",
                    "version": "2026-08-25"
                }
            ],
            "dev.ucp.shopping.order": [
                {
                    "spec": "https://ucp.dev/2026-08-25/specification/shopping/order",
                    "schema": "https://ucp.dev/2026-08-25/schemas/shopping/order.json",
                    "version": "2026-08-25"
                }
            ],
            "dev.ucp.shopping.checkout": [
                {
                    "spec": "https://ucp.dev/2026-08-25/specification/shopping/checkout",
                    "schema": "https://ucp.dev/2026-08-25/schemas/shopping/checkout.json",
                    "version": "2026-08-25"
                }
            ],
            "dev.ucp.shopping.discount": [
                {
                    "spec": "https://ucp.dev/2026-08-25/specification/shopping/extensions/discount",
                    "schema": "https://ucp.dev/2026-08-25/schemas/shopping/discount.json",
                    "extends": [
                        "dev.ucp.shopping.checkout",
                        "dev.ucp.shopping.cart"
                    ],
                    "version": "2026-08-25"
                }
            ],
            "dev.ucp.shopping.fulfillment": [
                {
                    "spec": "https://ucp.dev/2026-08-25/specification/shopping/extensions/fulfillment",
                    "config": {
                        "multi_destination": [],
                        "method_combinations": [
                            [
                                "digital_api_delivery"
                            ]
                        ]
                    },
                    "schema": "https://ucp.dev/2026-08-25/schemas/shopping/fulfillment.json",
                    "extends": "dev.ucp.shopping.checkout",
                    "version": "2026-08-25"
                }
            ],
            "dev.ucp.common.location.lookup": [
                {
                    "spec": "https://ucp.dev/2026-08-25/specification/common/location/lookup",
                    "schema": "https://ucp.dev/2026-08-25/schemas/common/location_lookup.json",
                    "version": "2026-08-25"
                }
            ],
            "dev.ucp.common.location.search": [
                {
                    "spec": "https://ucp.dev/2026-08-25/specification/common/location/search",
                    "schema": "https://ucp.dev/2026-08-25/schemas/common/location_search.json",
                    "version": "2026-08-25"
                }
            ],
            "dev.ucp.shopping.buyer_consent": [
                {
                    "spec": "https://ucp.dev/2026-08-25/specification/shopping/extensions/buyer-consent",
                    "schema": "https://ucp.dev/2026-08-25/schemas/shopping/buyer_consent.json",
                    "extends": "dev.ucp.shopping.checkout",
                    "version": "2026-08-25"
                }
            ],
            "dev.ucp.common.identity_linking": [
                {
                    "spec": "https://ucp.dev/2026-08-25/specification/common/identity-linking/",
                    "config": {
                        "scopes": {
                            "dev.ucp.shopping.order:read": [],
                            "dev.ucp.shopping.checkout:manage": []
                        }
                    },
                    "schema": "https://ucp.dev/2026-08-25/schemas/common/identity_linking.json",
                    "version": "2026-08-25"
                }
            ],
            "dev.ucp.shopping.catalog.lookup": [
                {
                    "spec": "https://ucp.dev/2026-08-25/specification/shopping/catalog/lookup",
                    "schema": "https://ucp.dev/2026-08-25/schemas/shopping/catalog_lookup.json",
                    "version": "2026-08-25"
                }
            ],
            "dev.ucp.shopping.catalog.search": [
                {
                    "spec": "https://ucp.dev/2026-08-25/specification/shopping/catalog/search",
                    "schema": "https://ucp.dev/2026-08-25/schemas/shopping/catalog_search.json",
                    "version": "2026-08-25"
                }
            ],
            "dev.ucp.common.payment.ap2_mandate": [
                {
                    "spec": "https://ucp.dev/2026-08-25/specification/payment/extensions/ap2-mandates",
                    "schema": "https://ucp.dev/2026-08-25/schemas/common/payment_ap2_mandate.json",
                    "extends": "dev.ucp.shopping.checkout",
                    "version": "2026-08-25"
                }
            ]
        },
        "instructions": "Browse B2A/MCP API credits and tools via search_catalog or lookup_catalog, create a checkout session with create_checkout, and complete settlement via x402 Base Mainnet USDC (0xEC5275D5b03bc390FcA63D902d0B2D0Db2eb5573) or Stripe MPP session pass.",
        "payment_handlers": {
            "com.stripe.mpp.session_credit": [
                {
                    "id": "stripe-mpp-pass",
                    "config": {
                        "partial_payment": false,
                        "requires_identity_linking": false
                    },
                    "version": "2026-08-25"
                }
            ],
            "org.x402.payment.delegate_checkout": [
                {
                    "id": "x402-base-usdc",
                    "config": {
                        "payTo": "0xEC5275D5b03bc390FcA63D902d0B2D0Db2eb5573",
                        "network": "eip155:8453",
                        "currency": "USDC",
                        "store_url": "https://assay.agentdiet.dev",
                        "checkout_url": "https://assay.agentdiet.dev/api/v1/billing/checkout"
                    },
                    "version": "2026-08-25"
                }
            ]
        },
        "supported_versions": {
            "2026-01-23": "https://assay.agentdiet.dev/.well-known/ucp?version=2026-01-23"
        }
    },
    "keys": [
        {
            "x": "8qIKqDM0qg6uy39ZQHvJXr85Qw0X_piFz6golCsE7eE",
            "y": "U7t1GXTNuSOvnoHAY2djNOV3zVnZyaatCY_0oSTrEQY",
            "alg": "ES256",
            "crv": "P-256",
            "kid": "imperium-ucp-p256-2026",
            "kty": "EC",
            "use": "sig"
        },
        {
            "x": "bcbWwOzGnHjDuz4LNC2nRPujrSs12_orR9xlXZLdFb8",
            "y": "lvUXMulVOpNxLNqe3j7LGcSd1i-Day1w_jltLOg3bHA",
            "alg": "ES256",
            "crv": "P-256",
            "kid": "imperium-ap2-p256-2026",
            "kty": "EC",
            "use": "sig"
        }
    ]
}
What goes in a UCP profile →Check your JSON in the Validator →Guides by store platform →
/llms.txt as served 2.2 KB 
# Assay — A2A & MCP Pre-Flight Security Observatory & TDQS Certifier

> Live A2A & MCP endpoint security auditor, Tool Definition Quality Score (TDQS) certifier, prompt-injection scanner, and cryptographic trust oracle.

**Assay — A2A & MCP Pre-Flight Security Observatory & TDQS Certifier** (`https://assay.agentdiet.dev`) is a production B2A, A2A v0.3.0, Streamable HTTP MCP (2025-11-25), x402 v2 (Base, Arbitrum, Polygon, Optimism, Avalanche USDC to `0xEC5275D5b03bc390FcA63D902d0B2D0Db2eb5573`), IETF MPP, and L402 execution node. Free zero-cost sandbox previews are available at `GET https://assay.agentdiet.dev/v1/try/certify`.

## Documentation

- [Overview & Quickstart](https://assay.agentdiet.dev/index.md): Architecture overview, free sandbox endpoints, and autonomous payment rails
- [Agent Skill & Integration Guide](https://assay.agentdiet.dev/AGENTS.md): Installation commands, MCP client configuration, and usage examples
- [Sitemap & Documentation Hierarchy](https://assay.agentdiet.dev/sitemap.md): Complete markdown hierarchy of all pages and protocol endpoints
- [Protocol & Terminology Glossary](https://assay.agentdiet.dev/glossary.md): Definitions for x402, IETF MPP, L402, A2A, MCP, OASF, and ERC-8004
- [Pricing & Plans](https://assay.agentdiet.dev/pricing.md): Free sandbox tier, $0.002/call x402 micropayments, Pro Monthly, and Enterprise SLA

## API & Protocol Manifests

- [OpenAPI 3.1 Specification](https://assay.agentdiet.dev/openapi.json): Complete REST API, x402 v2, and IETF MPP payment specification
- [A2A v0.3.0 Agent Card](https://assay.agentdiet.dev/.well-known/agent-card.json): Linux Foundation Agent-to-Agent discovery card and skills manifest
- [MCP Server Card](https://assay.agentdiet.dev/.well-known/mcp.json): Model Context Protocol Streamable HTTP server card (SEP-2127)
- [Wildcard agents.json](https://assay.agentdiet.dev/.well-known/agents.json): Wildcard agents.json v0.1.0 operation flows
- [x402 v2 Payment Discovery](https://assay.agentdiet.dev/.well-known/x402): 5-chain EVM USDC x402 resource manifest
- [Full LLM Documentation](https://assay.agentdiet.dev/llms-full.txt): Extended API schemas, sample payloads, and multi-agent workflow reference
Is assay.agentdiet.dev your store?
Claim it with one DNS record.
Claim this store Send an agent to shop here ↗

Status badge

Markdown · 
[![UCP Status](https://ucpchecker.com/badge/assay.agentdiet.dev)](https://ucpchecker.com/status/assay.agentdiet.dev)

Questions

Can UCP agents buy from assay.agentdiet.dev?
Through its REST and MCP services, an agent can search the catalogue, build a cart and start a checkout. This is what the store declares and what our check reached; an observed agent run shows how far an agent actually gets.
Is assay.agentdiet.dev ready for UCP agents?
assay.agentdiet.dev publishes a valid UCP profile and scores 100/100 (grade A). Our check found nothing to fix.
What is a UCP profile?
The JSON file a store publishes at /.well-known/ucp to tell UCP agents which services it offers, how to call them and how it takes payment. The spec calls it the business profile. assay.agentdiet.dev's is 7.4 KB, written for UCP 2026-08-25. What goes in a UCP profile.
How was assay.agentdiet.dev checked?
With public requests on 21 Oct 2026: we read /.well-known/ucp and robots.txt, validated the profile against UCP 2026-08-25, checked that its spec and schema links resolve. No sign-in and no purchase. How we check.