A walled garden is a platform that deliberately restricts outside AI agents and crawlers from reading its content or acting inside its accounts, so that discovery, data, and transactions stay within its own ecosystem. In AI commerce, the term describes large marketplaces that block third-party shopper agents while building their own in-house assistants, keeping ad revenue, first-party data, and checkout under their control.
The walls go up at three levels: disallowing an AI crawler's user-agent in robots.txt, challenging or blocking agent traffic at the CDN or WAF, and legal enforcement against unauthorized access to logged-in accounts, the layer at issue in Amazon's 2026 preliminary injunction against Perplexity's Comet browser (attributed and hedged, as it is a preliminary order in ongoing litigation).
A walled garden is distinct from protocol choice: a platform can back an open checkout standard for authorized partners and still gate crawlers it hasn't sanctioned. For brands, the practical response is to keep your own storefront open and legible and to be present on more than one surface, so a single platform's closed posture doesn't erase you from agentic commerce.