A way for AI agents to pay

R2.4

Can an agent pay by a method built for agents?

Why it matters: An AI agent that can't pay can't finish the job it was given.
What Lens looks for: We looked for a payment method built for AI agents, such as an x402 or MPP payment request, or AP2 mandates.
Where it sits: Purchase · Check 3 of 3
Needed for: No stage needs it. It counts toward its group.
Builds on: A checkout for AI agents R2.3
Needed by: Nothing
Usually fixed by: Finance · Weeks

What to do

Accept x402, MPP or L402 payments, or offer AP2 mandates or an agent-usable payment handler through UCP.

Purchase

Can an agent buy without a browser?

The definition

Definition: A payment method built for agents is one of these, each read by its own specification, whether or not a legal context pairs it. An x402 PaymentRequired document, v1 in a 402's JSON body or v2 in the PAYMENT-REQUIRED header, over HTTP or carried in an MCP answer, with at least one option carrying every member its version requires. An MPP Payment challenge in WWW-Authenticate with id, realm, method, intent and a request that decodes to a JSON object; expires is optional and, where given, an RFC 3339 timestamp. An L402 challenge (or LSAT, its earlier name) in WWW-Authenticate with a token and a BOLT 11 invoice. An A402 bill in a 402's Payment-Needed header stating an order number, an amount, a currency and the seller's signature. An OpenAPI operation with x-payment-info giving intent, method and amount. An AP2 declaration: a UCP profile declaring dev.ucp.common.payment.ap2_mandate with extends including dev.ucp.shopping.checkout and at least one EC key (P-256, P-384 or P-521) in keys[], or an A2A agent card declaring the AP2 extension. A payment extension an A2A agent card declares, named in lists.a2aPaymentExtensions. A UCP payment handler named in lists.ucpAgentHandlers, in a profile that declares dev.ucp.shopping.checkout: the agent acquires from it the credential it submits to complete the checkout. A 402 carrying crawler-price licenses content to crawlers; it is recorded as an observation and meets no rung.
Passes when: At least one recognised payment challenge or declaration is observed. A route in lists.routes listed for this rung, or for a higher rung of the same dimension, meets it; the result names the route.
Decided by: A rule
Evidence: The 402 responses; the MCP answers; the UCP profile; the OpenAPI document; the A2A agent card
Steps: home, payment, wellknown, ucp.handshake
Made as: anon, ucp
Standards: x402 v1 and v2 specificationsMPP (draft-httpauth-payment-01)L402 (bLIP-26)A402 (ACT 2.1)AP2 v0.2 (checkout and payment mandates)UCP 2026-08-25 (payment handlers)A2A v1.0 (extensions)