Official links
Relationships
| From | Type | To | Evidence |
|---|---|---|---|
| evt-acp-docs-home | DISCUSSES | acp | Observed |
| evt-acp-docs-sellers | DISCUSSES | acp | Observed |
| evt-openai-instant-checkout-2025-09-29 | DISCUSSES | acp | Verified |
| evt-stripe-openai-acp-2025-09-29 | DISCUSSES | acp | Verified |
| openai | BUILDS | acp | Verified |
| stripe | BUILDS | acp | Verified |
Recent events
ACP documentation home states the job to be done: programmatic checkout
The Agentic Commerce Protocol documentation home describes a programmatic exchange between buyers, their agents, and sellers to complete a purchase, with agents rendering checkout UI and sellers keeping existing back-end models and payment processing.
ObservedSourceACP docs define merchant checkout-session REST endpoints
Official Agentic Commerce Protocol seller documentation specifies REST checkout session create/get/update/complete/cancel endpoints. Later versions require capability declarations in checkout responses. This is a different machine contract from x402’s 402 + header retry.
ObservedSourceOpenAI opens Instant Checkout and publishes ACP as an open standard
OpenAI’s 29 September 2025 note describes Instant Checkout powered by ACP, built with Stripe, and open-sources the protocol so other agents and merchants can implement checkout sessions. This is in-chat retail, not an API micropayment 402.
VerifiedSourceStripe and OpenAI release the Agentic Commerce Protocol with Instant Checkout
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.
VerifiedSource
Source
verified · https://zfinia.com/methodology