Verified65% confidenceFactExact time
x402 is an open protocol that reuses the 402 status code (Payment Required) from the HTTP protocol, enabling software (especially AI Agents) to call APIs on a per-request pay-as-you-go basis and settle directly with cryptocurrency (typically USDC), without requiring accounts, API keys, or traditional checkout pages.
3
Sources
65%
Confidence
Long-term
Relevance
9/23/2026
First Seen
Sources
Related Entities
Related Claims
UnverifiedAgent Code Payments currently supports the X402 protocol, a modernized implementation of the HTTP 402 status code.78% similarUnverifiedThe Facilitator (settlement party) is a key component in the x402 architecture, responsible for verifying payment signatures submitted by Agents and broadcasting transactions on the blockchain, allowing API providers to receive instant proof of payment without running their own blockchain nodes.66% similarUnverifiedXMPP was standardized by the IETF as RFC 3920/3921 in 2004, and its federated architecture allows different servers to communicate with each other.62% similarUnverifiedThe poster's marketplace interface manifest uses x402-v2, the Base chain (eip155:8453), USDC, a payTo address, with a listing fee of 0.01.61% similarUnverifiedXMPP is an open instant messaging protocol based on XML that natively supports federation, allowing users on different servers to communicate across servers.59% similar
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