Agent-Ready Commerce, Part 5: Keeping ACP, MCP, and AP2 Adapters Thin

Agent-ready commerce requires keeping ACP, MCP, and AP2 adapters thin to prevent architectural drift, ensuring they only translate external protocol requests without performing business logic. Meanwhile, checkout must be modeled as a state machine rather than a form endpoint. Unlike read-only discovery or comparison, checkout mutates commercial state by modifying carts, locking prices, revalidating inventory, and calculating shipping options before an order is committed, making state management critical for platform stability.