Stripe and OpenAI release the Agentic Commerce Protocol with Instant Checkout

A checkout-session protocol for agents, distinct from x402’s HTTP 402 challenge.

On 29 September 2025 Stripe announced that it powers Instant Checkout in ChatGPT and released the Agentic Commerce Protocol, co-developed with OpenAI. US ChatGPT users could buy from US Etsy businesses in-chat, with Shopify merchants described as coming soon. ACP is a merchant checkout-session standard, not Coinbase x402.

Why it matters

Most consumer agent purchases will look like delegated checkout, not USDC micropayments. Builders must not confuse ACP with x402.

Source: Stripe Newsroom

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