UCP Checker & Validator — Universal Commerce Protocol (UCP) Status

Every store gets a score.

A score from 0 to 100 for how well your store's UCP profile follows the spec and what it lets a UCP agent do: three weighted parts in one number, with the fixes that raise it.

See how scoring works Leaderboard

Discovery 30%96

Conformance 40%92

Capability 30%95

Grade bands A 85+ B 70+ C 50+ D 30+ F 0

The live state of the UCP market

We check about 25,000 stores: a public record of who publishes a UCP profile and how well it follows the spec. The methodology is public.

91%of scored stores are grade A

90average UCP Score

58%of valid profiles are on 2026-08-25

69%of profiles answer in under 200 ms

Releases in valid profilesEvery release and what changed

2026-08-25 · 58%2026-04-08 · 42%

See the stats Read the methodology

We don't just read the profile. We test what an agent actually does.

Most checks stop at the profile. We look at both sides: what a store declares, and what happened when an agent used it in our runs. Where the two differ is what's worth fixing.

UCP Checker reads

What the store declares

"ucp": {
  "version": "2026-08-25",
  "services": { "dev.ucp.shopping": [ mcp, rest ] },
  "capabilities": { "…checkout": […], "…cart": […] }
}

Fetched from /.well-known/ucp and validated against the release it names, across every store we check.

UCP Playground runs

What an agent could do

search_cataloganswered
get_productanswered
create_cartanswered
create_checkouthanded to the buyer

A real model shops the store over UCP. Open UCP Playground ↗

The protocol agents use to shop

The Universal Commerce Protocol turns a store into something an agent can read and use: find products, build a cart, check out. UCP Checker reads about 25,000 stores, so you can see what works, what breaks, and what's next.

One JSON file at `/.well-known/ucp`

A store publishes one UCP profile: its services, capabilities, transports and payment handlers. The guide

Read first by UCP agents

A UCP agent fetches the profile before anything else to learn what the store offers and how to buy from it. Without one, it has nothing to go on.

Compliance is not binary

A profile can parse and still not work. We look at conformance, capability coverage and response time, not just whether the file is valid JSON.

An agent shopping our sandbox store over UCP, end to end. The requests and answers are recorded from the store.

Everything you need to ship UCP

From the first check to a test with a real agent: free tools for your whole UCP surface.

From a URL to a status page in three steps

No SDK, no code changes. Enter a domain and UCP Checker fetches, validates and publishes what it found.

Step 1
We fetch your profile
We request /.well-known/ucp the way an agent would, with TLS checks and a short timeout, and read robots.txt for which bots it lets in.
Step 2
We validate it against the spec
Against the release your profile declares: required fields, capabilities, transports and payment handlers, then we call the endpoints it names.
Step 3
We publish the result
Your store gets a status page and a score page with what to fix, and the result counts towards the public stats.

Check a store How we check

See agentic readiness on every store you visit

A free Chrome extension that reads /.well-known/ucp on the store you're on: its release, capabilities, payment handlers and ways in, and which bots its robots.txt lets in.

Green dot: the store publishes a valid UCP profile.
Reads only /.well-known/ucp and robots.txt, never your cookies, history or the page.
Share what it finds: sends the store's domain and its UCP profile to UCP Checker, nothing about you.

Add to Chrome, free About the extension

What a store's catalogue tells an agent

The Catalog Validator searches a store over UCP, looks each product up again, and checks every field against the spec: prices, variants, availability, images. Here it is on our sandbox flower shop.

Run the Catalog Validator

search_catalog "roses", 3 of 24 shownMCP · 702ms

bouquet_roses as the agent received it

{
  "id": "bouquet_roses",
  "title": "Bouquet of Red Roses",
  "description": {
    "plain": "A classic dozen of long-stem red roses."
  },
  "handle": "bouquet_roses",
  "url": "https://flowers.ucpsandbox.com/products/bouquet_roses",
  "price_range": {
    "min": {
      "amount": 3500,
      "currency": "USD"
    },
    "max": {
      "amount": 3500,
      "currency": "USD"
    }
  },
  "categories": [
    {
      "value": "Bouquets"
    }
  ],
  "tags": [
    "roses",
    "red",
    "classic",
    "romance"
  ],
  "variants": [
    {
      "id": "bouquet_roses",
      "title": "Bouquet of Red Roses",
      "description": {
        "plain": "A classic dozen of long-stem red roses."
      },
      "sku": "BOUQUET_ROSES",
      "url": "https://flowers.ucpsandbox.com/products/bouquet_roses",
      "price": {
        "amount": 3500,
        "currency": "USD"
      },
      "availability": {
        "available": true,
        "status": "in_stock"
      },
      "media": [
        {
          "type": "image",
          "url": "https://flowers.ucpsandbox.com/images/flowers/bouquet_roses.webp",
          "alt_text": "Bouquet of Red Roses"
        }
      ],
      "fulfillment": {
        "methods": [
          {
            "type": "shipping",
            "availability": {
              "available": true
            }
          },
          {
            "type": "pickup",
            "description": {
              "plain": "Free. Collect from one of our shops, usually ready within two hours of opening."
            },
            "availability": {
              "available": true
            }
          }
        ]
      }
    }
  ],
  "media": [
    {
      "type": "image",
      "url": "https://flowers.ucpsandbox.com/images/flowers/bouquet_roses.webp",
      "alt_text": "Bouquet of Red Roses",
      "width": 600,
      "height": 600
    }
  ]
}

set_anniversary_red as the agent received it

{
  "id": "set_anniversary_red",
  "title": "Anniversary Reds",
  "description": {
    "plain": "Twelve red roses, chocolates and a card."
  },
  "handle": "set_anniversary_red",
  "url": "https://flowers.ucpsandbox.com/products/set_anniversary_red",
  "price_range": {
    "min": {
      "amount": 5200,
      "currency": "USD"
    },
    "max": {
      "amount": 5200,
      "currency": "USD"
    }
  },
  "categories": [
    {
      "value": "Occasions"
    }
  ],
  "tags": [
    "anniversary",
    "roses",
    "gift"
  ],
  "variants": [
    {
      "id": "set_anniversary_red",
      "title": "Anniversary Reds",
      "description": {
        "plain": "Twelve red roses, chocolates and a card."
      },
      "sku": "SET_ANNIVERSARY_RED",
      "url": "https://flowers.ucpsandbox.com/products/set_anniversary_red",
      "price": {
        "amount": 5200,
        "currency": "USD"
      },
      "availability": {
        "available": true,
        "status": "in_stock"
      },
      "media": [
        {
          "type": "image",
          "url": "https://flowers.ucpsandbox.com/images/flowers/set_anniversary_red.webp",
          "alt_text": "Anniversary Reds"
        }
      ],
      "fulfillment": {
        "methods": [
          {
            "type": "shipping",
            "availability": {
              "available": true
            }
          },
          {
            "type": "pickup",
            "description": {
              "plain": "Free. Collect from one of our shops, usually ready within two hours of opening."
            },
            "availability": {
              "available": true
            }
          }
        ]
      }
    }
  ],
  "media": [
    {
      "type": "image",
      "url": "https://flowers.ucpsandbox.com/images/flowers/set_anniversary_red.webp",
      "alt_text": "Anniversary Reds",
      "width": 600,
      "height": 600
    }
  ]
}

preserved_roses_box as the agent received it

{
  "id": "preserved_roses_box",
  "title": "Preserved Roses Box",
  "description": {
    "plain": "Nine preserved red roses in a black box, last a year without water."
  },
  "handle": "preserved_roses_box",
  "url": "https://flowers.ucpsandbox.com/products/preserved_roses_box",
  "price_range": {
    "min": {
      "amount": 8900,
      "currency": "USD"
    },
    "max": {
      "amount": 8900,
      "currency": "USD"
    }
  },
  "categories": [
    {
      "value": "Dried & Preserved"
    }
  ],
  "tags": [
    "preserved",
    "roses",
    "gift"
  ],
  "variants": [
    {
      "id": "preserved_roses_box",
      "title": "Preserved Roses Box",
      "description": {
        "plain": "Nine preserved red roses in a black box, last a year without water."
      },
      "sku": "PRESERVED_ROSES_BOX",
      "url": "https://flowers.ucpsandbox.com/products/preserved_roses_box",
      "price": {
        "amount": 8900,
        "currency": "USD"
      },
      "availability": {
        "available": true,
        "status": "in_stock"
      },
      "media": [
        {
          "type": "image",
          "url": "https://flowers.ucpsandbox.com/images/flowers/preserved_roses_box.webp",
          "alt_text": "Preserved Roses Box"
        }
      ],
      "fulfillment": {
        "methods": [
          {
            "type": "shipping",
            "availability": {
              "available": true
            }
          },
          {
            "type": "pickup",
            "description": {
              "plain": "Free. Collect from one of our shops, usually ready within two hours of opening."
            },
            "availability": {
              "available": true
            }
          }
        ]
      }
    }
  ],
  "media": [
    {
      "type": "image",
      "url": "https://flowers.ucpsandbox.com/images/flowers/preserved_roses_box.webp",
      "alt_text": "Preserved Roses Box",
      "width": 600,
      "height": 600
    }
  ]
}

{
  "jsonrpc": "2.0",
  "id": 2,
  "method": "tools/call",
  "params": {
    "name": "search_catalog",
    "arguments": {
      "meta": {
        "ucp-agent": {
          "profile": "https://ucpchecker.com/.well-known/ucp"
        }
      },
      "catalog": {
        "query": "roses"
      }
    }
  }
}

200 · MCP tools/call

{
  "ucp": {
    "version": "2026-08-25",
    "capabilities": {
      "dev.ucp.shopping.catalog.search": [
        {
          "version": "2026-08-25"
        }
      ],
      "dev.ucp.shopping.catalog.lookup": [
        {
          "version": "2026-08-25"
        }
      ],
      "dev.ucp.shopping.fulfillment": [
        {
          "version": "2026-08-25"
        }
      ]
    }
  },
  "products": [
    "bouquet_roses · Bouquet of Red Roses",
    "bouquet_pink_roses · Pink Roses Bouquet",
    "preserved_roses_box · Preserved Roses Box",
    "arr_hatbox_roses · Roses in a Hat Box",
    "bouquet_white_roses · White Roses Bouquet",
    "bouquet_yellow_roses · Yellow Roses Bouquet",
    "plant_rose_bush · Potted Rose Bush",
    "arr_buttonhole · Rose Buttonhole",
    "set_anniversary_red · Anniversary Reds",
    "set_valentines_dozen · Valentine's Dozen",
    "arr_vase_white · All-White Vase Arrangement",
    "set_birthday_bright · Birthday Brights",
    "arr_bridal_bouquet · Bridal Bouquet",
    "arr_bridesmaid · Bridesmaid Bouquet",
    "set_christmas_table · Christmas Table Centre",
    "arr_flower_crown · Flower Crown",
    "arr_table_runner · Foliage Table Runner",
    "arr_hatbox_mixed · Garden Hat Box",
    "plant_herb_box · Kitchen Herb Box",
    "bouquet_lisianthus · Lisianthus Bouquet",
    "arr_low_table · Low Table Centrepiece",
    "set_new_baby_blue · New Baby, Blue",
    "set_new_baby_pink · New Baby, Pink",
    "arr_sympathy_heart · Sympathy Heart"
  ],
  "pagination": {
    "has_next_page": true,
    "cursor": "24",
    "total_count": 27
  }
}

flowers.ucpsandbox.com24 products checked

32pass

1to improve

0fail

Every product has a formatted (HTML) description24 products give plain text only. Agents that show rich text have nothing to format.

Reads: description.html
Found: { "plain": "A classic dozen of long-stem red roses." }
Across: 0 of 24 products

Every price has an amount and a currency, in cents
Reads
variants[].price
Found
{ "amount": 3500, "currency": "USD" }
Across
32 of 32 variants
Every variant gives an availability status
Reads
variants[].availability.status
Found
"in_stock"
Across
32 of 32 variants
Variant prices sit inside the product's price range
Reads
price_range.min ≤ variants[].price ≤ price_range.max
Found
3500 ≤ 3500 ≤ 3500
Across
32 of 32 variants
Every product has at least one image, with a type and URL
Reads
media[].type, media[].url
Found
"image", https://flowers.ucpsandbox.com/images/flowers/bouquet_roses.webp
Across
24 of 24 products
Looking a product up by its id returns the same product
Reads
lookup_catalog { ids: ["bouquet_roses"] }
Found
same id, title, prices and media; lookup adds inputs[] as the spec says
Across
1 lookup
The same search returns the same products
Reads
search_catalog { query: "roses" }, twice
Found
the same 24 ids in the same order
Across
2 searches

and 26 more checks, each with the field it reads. Run them on a store

Get the agentic commerce digest every Monday

What changed in the spec and across the stores we check, in one short email. See a sample

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14 Oct 2026

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13 Oct 2026

UCP Business Directory and Business Identity: Amazon's Three RFCs Explained

11 Oct 2026

UCP Local Services: What the Charter for a Booking Council Proposes

8 Oct 2026

Personal Agent Protocol (Poppy) v0.1: What the Spec Says and How It Fits With UCP

8 Oct 2026

Google's UCP Integration Hub in Merchant Center: How to Get Your Store In

Questions about UCP Checker

What is a UCP checker?

A tool that fetches a store's UCP profile at /.well-known/ucp, validates it against the Universal Commerce Protocol release it declares, and shows what an agent could do there. UCP Checker also calls the endpoints the profile names and publishes the result on a status page.

What is the Universal Commerce Protocol?

An open standard that lets an agent find out what a store offers and buy from it: search the catalogue, build a cart, check out and pay. A store describes all of this in one JSON file, its UCP profile. How UCP works

How is the UCP Score worked out?

Three parts in one number from 0 to 100: Discovery (30%), Conformance (40%) and Capability (30%). Grade A is 85 or more. The methodology has every rule.

What is the difference between the UCP Checker and the UCP Validator?

The checker starts from a domain: it fetches the live profile, calls the endpoints it names and publishes a status page. The UCP Validator starts from a profile you paste, so you can test one before it goes live, against any release. The Catalog Validator checks what catalogue search and lookup return.

How do I publish a UCP profile for my store?

Many store platforms publish one for you once UCP is switched on; the platforms page shows which. Otherwise you serve one JSON file at /.well-known/ucp; the /.well-known/ucp guide walks through every field. Then check your store here.

Which UCP release do you check against?

The one your profile declares, with that release's rules. The latest is 2026-08-25. The UCP Validator checks a pasted profile against any release.

What does Verified mean?

The store publishes a UCP profile that passes against its release, and we could reach it. Verified stores can show the status badge.

Is UCP Checker free?

Yes. Checks, status pages, the validators and the badges are free, with no account.

The UCP Checker & Validator
for agentic commerce

Every store gets a score.

The live state of the UCP market

We don't just read the profile. We test what an agent actually does.

What the store declares

What an agent could do

The protocol agents use to shop

One JSON file at `/.well-known/ucp`

Read first by UCP agents

Compliance is not binary

Everything you need to ship UCP

Check

Measure

Build and test

From a URL to a status page in three steps

We fetch your profile

We validate it against the spec

We publish the result

See agentic readiness on every store you visit

What a store's catalogue tells an agent

Get the agentic commerce digest every Monday

Latest from the UCP Checker blog

UCP in the Agent Chain of Trust: What the GoDaddy, Infoblox, Google and Cloudflare Demo Checks

UCP for B2B: A Procurement Council Charter, Quotes and Price on Request

UCP Business Directory and Business Identity: Amazon's Three RFCs Explained

UCP Local Services: What the Charter for a Booking Council Proposes

Personal Agent Protocol (Poppy) v0.1: What the Spec Says and How It Fits With UCP

Google's UCP Integration Hub in Merchant Center: How to Get Your Store In

Questions about UCP Checker

Sign in to UCP Checker

The UCP Checker & Validatorfor agentic commerce

Every store gets a score.

The live state of the UCP market

We don't just read the profile. We test what an agent actually does.

What the store declares

What an agent could do

The protocol agents use to shop

One JSON file at /.well-known/ucp

Read first by UCP agents

Compliance is not binary

Everything you need to ship UCP

Check

Measure

Build and test

From a URL to a status page in three steps

We fetch your profile

We validate it against the spec

We publish the result

See agentic readiness on every store you visit

What a store's catalogue tells an agent

Get the agentic commerce digest every Monday

Latest from the UCP Checker blog

UCP in the Agent Chain of Trust: What the GoDaddy, Infoblox, Google and Cloudflare Demo Checks

UCP for B2B: A Procurement Council Charter, Quotes and Price on Request

UCP Business Directory and Business Identity: Amazon's Three RFCs Explained

UCP Local Services: What the Charter for a Booking Council Proposes

Personal Agent Protocol (Poppy) v0.1: What the Spec Says and How It Fits With UCP

Google's UCP Integration Hub in Merchant Center: How to Get Your Store In

Questions about UCP Checker

The UCP Checker & Validator
for agentic commerce

One JSON file at `/.well-known/ucp`