Merchant API MCP Access Service (alpha) launched with conversational product attributes

May 2026 updates added an alpha MCP service giving AI agents authorized, read-focused access to Merchant Center data and insights, a mapi-developer-assistant agent skill in the Code Assist Toolkit, new conversational attributes (question_and_answer, document_link, related_product, item_group_title, variant_option, popularity_rank), a full vehicle ads attribute set, UCP checkout product status notifications, a YouTube sub-API v1alpha and low-latency price/availability patches for allowlisted merchants.

Month-level date from Google's latest-updates page. The Merchant API docs now list 'Agentic tools' including the Merchant API MCP Access Service and the API Integration and Code Assist Toolkit.