What it means
The API answered with HTTP 503 and the error code agentic_commerce_not_enabled.
Buying through an AI agent is not switched on for live payments yet; it waits for Stripe’s approval. It works in Stripe test mode. Buy at /lifetime-plans meanwhile.
How to handle it
Every error is an RFC 9457 problem document (application/problem+json). Match on code, never on the message text. See errors for the full list.