Implementing the Universal Commerce Protocol (UCP) is your first step toward agentic commerce. But simply having a ucp.json file isn’t enough. You need to declare capabilities that allow AI agents to interact with your store programmatically.

In this guide, we’ll break down the most important UCP capabilities and how developers should implement them.

1. Product Search (dev.ucp.shopping.search)

The most fundamental capability of any storefront is the ability to find products. When an agent queries your store, it doesn’t scrape your frontend search results; it hits your declared search endpoint.

How it works: The agent sends a structured JSON payload containing the user’s intent, constraints (like max price), and desired attributes.

{
  "intent": "running shoes",
  "filters": {
    "price_max": 150,
    "size": "10W"
  }
}

Developer Implementation: You must map this payload to your backend search engine (like Algolia or Elasticsearch) and return a standardized array of product objects, complete with image_url, price, and stock_status.

2. Cart Management (dev.ucp.shopping.cart)

Once the agent finds the right product, it needs the ability to add it to a cart on the user’s behalf.

How it works: The agent sends a POST request to your cart endpoint with the specific sku or product_id and the desired quantity.

Developer Implementation: This is where authentication becomes tricky. Because the agent is acting on behalf of the user, you must support OAuth 2.0 or secure session handoffs. When the agent successfully adds the item, your API should return a deep link to the checkout page (checkout_url) so the user can complete the purchase seamlessly.

3. Order Status (dev.ucp.shopping.order_status)

Post-purchase experience is critical. Users frequently ask AI assistants, “Where is my package?”

Developer Implementation: Expose a read-only endpoint that accepts an order_id and returns the current shipping status, tracking number, and carrier information.

Conclusion

By implementing these core capabilities, you transform your store from a static catalog into an interactive API that AI agents can negotiate with. Use the UCP Profile Builder in the Commerce AI toolkit to scaffold your JSON configuration today!