UCP Pay

UCP Pay is Clink’s API-style checkout flow for supported merchants. It covers product discovery, checkout preparation, user authorization, payment completion, order retrieval, and digital delivery.

When to use UCP Pay

Use UCP Pay when the merchant supports UCP and the checkout needs structured product, fulfillment, order, or digital-delivery state. Use Browser Pay when the Agent needs to operate a regular merchant web page.

Payment flow

Discover a product with Catalog tools, or parse an exact product URL.
Confirm the SKU, options, quantity, price, currency, and fulfillment details.
Call create_checkout and continue according to its next_action.
Use update_checkout when the user changes supported checkout details.
Call complete_checkout once with the current confirmation identifiers.
Read the UCP order and wait for digital delivery when needed.

Sequence diagram

UCP Checkout uses its own Operation and order lifecycle. Do not call Browser Pay’s confirm_result for a UCP payment.

Code examples

The examples below are grouped by integration method. MCP uses tools/call to call Clink tools; RESTful API uses the platform integration HTTP endpoints. Both methods must use the latest operationId, actionId, and revision from the preceding response rather than reusing expired confirmation identifiers.

MCP

Search products

{
  "name": "discover_catalog",
  "arguments": {
    "query": "coffee voucher",
    "catalogLanguage": "en-US",
    "limit": 5
  }
}

Create checkout

{
  "name": "create_checkout",
  "arguments": {
    "merchantId": "merchant_example",
    "items": [
      {
        "productId": "product_example",
        "quantity": 1,
        "selected": {
          "size": "L"
        }
      }
    ],
    "fulfillmentType": "NO_SHIPPING_REQUIRED"
  }
}

Update checkout and complete payment

When next_action asks for shipping information, update the checkout using the current revision:

{
  "name": "update_checkout",
  "arguments": {
    "operationId": "<operation_id>",
    "actionId": "<current_action_id>",
    "expectedRevision": "<current_revision>",
    "shippingAddress": {
      "name": "Alex Smith",
      "addressLine1": "1 Example Street",
      "city": "San Francisco",
      "postalCode": "94105",
      "country": "US"
    }
  }
}

Read the updated response, then complete the checkout with the latest confirmation identifiers:

{
  "name": "complete_checkout",
  "arguments": {
    "operationId": "<operation_id>",
    "actionId": "<latest_action_id>",
    "expectedRevision": "<latest_revision>",
    "maxWaitSeconds": 30
  }
}

Read order and digital delivery

{
  "name": "get_ucp_order",
  "arguments": {
    "orderId": "<ucp_order_id>"
  }
}

For digital goods, continue waiting for delivery:

{
  "name": "wait_for_digital_delivery",
  "arguments": {
    "orderId": "<ucp_order_id>",
    "maxWaitSeconds": 120
  }
}

RESTful API

The endpoint paths and fields for the RESTful API depend on the UCP service enabled for your platform. The examples below show the corresponding HTTP calls; replace {UCP_API_BASE_URL}, {USER_ACCESS_TOKEN}, and placeholder IDs from responses with actual values.

Search products

curl -X POST "$UCP_API_BASE_URL/catalog/search" \
  -H "Authorization: Bearer $USER_ACCESS_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "query": "coffee voucher",
    "catalogLanguage": "en-US",
    "limit": 5
  }'

Create checkout

curl -X POST "$UCP_API_BASE_URL/checkouts" \
  -H "Authorization: Bearer $USER_ACCESS_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "merchant_id": "merchant_example",
    "items": [
      {
        "product_id": "product_example",
        "quantity": 1,
        "selected": {
          "size": "L"
        }
      }
    ],
    "fulfillment_type": "NO_SHIPPING_REQUIRED"
  }'

Update and complete checkout

curl -X PATCH "$UCP_API_BASE_URL/checkouts/<checkout_id>" \
  -H "Authorization: Bearer $USER_ACCESS_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "operation_id": "<operation_id>",
    "action_id": "<current_action_id>",
    "expected_revision": "<current_revision>",
    "shipping_address": {
      "name": "Alex Smith",
      "address_line1": "1 Example Street",
      "city": "San Francisco",
      "postal_code": "94105",
      "country": "US"
    }
  }'

curl -X POST "$UCP_API_BASE_URL/checkouts/<checkout_id>/complete" \
  -H "Authorization: Bearer $USER_ACCESS_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "operation_id": "<operation_id>",
    "action_id": "<latest_action_id>",
    "expected_revision": "<latest_revision>"
  }'

Read order and digital delivery

curl "$UCP_API_BASE_URL/orders/<ucp_order_id>" \
  -H "Authorization: Bearer $USER_ACCESS_TOKEN"

curl "$UCP_API_BASE_URL/orders/<ucp_order_id>/digital-delivery?max_wait_seconds=120" \
  -H "Authorization: Bearer $USER_ACCESS_TOKEN"

For fields, scopes, and recovery rules, see Catalog and UCP Checkout.

Get Started

Integration

Agent Solutions

Configure & Launch

Guides

Finance

When to use UCP Pay

Payment flow

Sequence diagram

Code examples

MCP

Search products

Create checkout

Update checkout and complete payment

Read order and digital delivery

RESTful API

Search products

Create checkout

Update and complete checkout

Read order and digital delivery

​When to use UCP Pay

​Payment flow

​Sequence diagram

​Code examples

​MCP

​Search products

​Create checkout

​Update checkout and complete payment

​Read order and digital delivery

​RESTful API

​Search products

​Create checkout

​Update and complete checkout

​Read order and digital delivery

When to use UCP Pay

Payment flow

Sequence diagram

Code examples

MCP

Search products

Create checkout

Update checkout and complete payment

Read order and digital delivery

RESTful API

Search products

Create checkout

Update and complete checkout

Read order and digital delivery