Google Plans To Adopt UCP Draft Spec For AI Mode Hotel Booking The Universal Commerce Protocol (UCP) project added a draft Lodging Booking specification to its GitHub repository on Sept. 25, and Google's developer documentation states the company plans to adopt the standard to power hotel booking in AI Mode over the coming months. Google began rolling out hotel booking in AI Mode for U.S. English users on August 27 with 10 hotel chains and online travel platforms, and the draft spec — developed with the Lodging Technical Council including Amadeus, Booking.com, Expedia, Google, Hilton, Marriott, and Trip.com — covers booking sessions via REST or MCP, real-time pricing, availability checks, and cancellation-policy extensions. Google's FAQ says UCP integration does not influence property or rate ranking, but entries with it get the direct booking option, with the business acting as merchant of record and retaining customer information. On Sept. 25, the Universal Commerce Protocol UCP project announced https://github.com/Universal-Commerce-Protocol/ucp/discussions/864 that a draft of its Lodging Booking feature has been added to the protocol’s GitHub repository. According to Google’s developer documentation https://developers.google.com/hotels/ucp/faq , the company plans to adopt this standard for its hotel booking feature in AI Mode over the coming months. Google began rolling out hotel booking in AI Mode https://www.searchenginejournal.com/google-starts-rolling-out-hotel-booking-in-ai-mode/587288/ for U.S. English users on August 27, working with 10 hotel chains and online travel platforms. The draft released on September 25 is the standard Google plans to adopt https://developers.google.com/hotels/ucp/faq for this feature. It gives hotels and booking sites their first published glimpse at the new standard, and Google’s FAQ explains details about ranking, attribution, and who keeps the customer relationship. What The Lodging Spec Covers The dev.ucp.lodging.booking specification describes how a platform manages booking sessions via REST or MCP, covering creation, updates, completion, or cancellation. The announcement https://github.com/Universal-Commerce-Protocol/ucp/discussions/864 lists features such as real-time pricing, availability checks, guest details, occupancy, check-in/check-out dates, and special requirements. The draft ties into payment extensions like deposits, deferred balances, and split payments from the August 25 release https://github.com/Universal-Commerce-Protocol/ucp/releases/tag/v2026-08-25 , along with a new extension for cancellation policies https://ucp.dev/draft/specification/lodging/extensions/cancellation-policy/ . It also includes shared UCP components such as identity linking and payment handlers. The spec https://ucp.dev/draft/specification/lodging/booking/ says PCI DSS compliance isn’t necessary for card payments. Bookings have to be finalized by a person through a trusted interface, except when using UCP’s AP2 Mandates extension for agent-led payments. Data models and bindings may evolve, with breaking changes possible, the draft banner warns. The Lodging Technical Council, comprising Amadeus, Booking.com, Expedia, Google, Hilton, Marriott, and Trip.com https://github.com/Universal-Commerce-Protocol/ucp/discussions/714 , is acknowledged in the announcement. How Google Plans To Use It Google’s FAQ https://developers.google.com/hotels/ucp/faq , updated Sept. 24, calls the first milestone booking and says: “Over the coming months, Google will adopt this standard to power its hotel booking feature on AI Mode.” The FAQ states that this milestone covers one room, with multiple rooms “potentially as a future extension.” The open spec’s data model allows a reservation to include one or more stay units. The FAQ clarifies https://developers.google.com/hotels/ucp/faq that choosing the booking integration “does not influence how we rank your properties or rates in listings.” However, entries with UCP integration get the direct booking option. The business acts as the merchant of record, keeping its own customer information and booking details, and its own terms and conditions govern the reservation. Google highlights that lifecycle events https://developers.google.com/hotels/ucp/faq shared via the API let a business see which traffic and payments came through Google’s AI surfaces rather than its own website or app. Also, before the final “Book” button appears, Google checks real-time price and availability via the partner’s API. While businesses don’t need the Google Pay API on their site, their payment provider must support processing Google’s tokens. The FAQ mentions https://developers.google.com/hotels/ucp/faq that AP2 can act as a payment layer within UCP for future agent-led transactions, though it stops short of calling it required. For now, Google’s UCP for Lodging page https://developers.google.com/hotels/ucp directs interested businesses to join a waitlist, with detailed onboarding instructions and specifications “coming soon.” How We Got Here The Lodging Technical Council was set up on August 11 https://github.com/Universal-Commerce-Protocol/ucp/discussions/714 . UCP’s release on August 25 introduced the structure needed to expand beyond retail. In my update on August 31 https://www.searchenginejournal.com/ucp-releases-spec-update-with-schema-changes/587590/ , I shared that the lodging specifications were still in development, with no release timeline at that point. Back in May at Google Marketing Live, Google connected hotel booking to UCP https://blog.google/products-and-platforms/products/shopping/shopping-updates-google-marketing-live/ , but its August 27th launch post didn’t specify whether all integrated partners use the protocol. Why This Matters UCP now offers a public booking contract for lodging, expanding from a council and structure a month ago. The draft explains how a platform and a hotel share information to make reservations, including details like rate plans, occupancy, payment schedules, and cancellation policies. Google’s documents https://developers.google.com/hotels/ucp/faq settle a few commercial questions for hotel and travel marketers. Joining the integration doesn’t change property ranking, and the business continues to act as the merchant of record. Plus, UCP reservations can be distinguished from direct bookings. The current documentation doesn’t yet offer options beyond the waitlist. Looking Ahead The draft is open for feedback on GitHub https://github.com/Universal-Commerce-Protocol/ucp/discussions/864 . Neither Google’s FAQ https://developers.google.com/hotels/ucp/faq nor its lodging page gives a date for the AI Mode switch or says which of the existing AI Mode booking partners will move to the standard. Watch for a stable lodging release, Google opening onboarding, and additions to the booking spec, starting with the multi-room extension the FAQ calls a possibility. Featured Image: MAYA LAB/Shutterstock