x402
Properties
tags
gen_aigen_ai/agents
created
03.04.2026, 12:00
modified
06.09.2026, 10:58
published
Empty
sources
x402 — Payment Required · x402 on Solana · x402-foundation/x402 · Overview — x402 (CDP docs)
topics
Agent Payment, Payment Protocol
authors
Jakub
ai-assisted
Yes
- Internet-native payment protocol built on the HTTP 402 Payment Required status code
- Enables any API or web service to require stablecoin payment before serving content (no accounts, subscriptions)
- Developed by the Coinbase Development Platform team; Apache 2.0 license
# Extensions
- x402 Bazaar
- Discovery layer — hybrid semantic search over payable x402 endpoints, indexed by the CDP Facilitator
- x402 in the CDP SDK
- Coinbase’s CDP SDK primitives: managed wallets, hosted facilitator, and client-side spend controls on top of the
@x402/*packages
- Coinbase’s CDP SDK primitives: managed wallets, hosted facilitator, and client-side spend controls on top of the
# Components
- Network, token, and currency agnostic; backwards compatible with existing HTTP infrastructure
- Facilitator — an intermediary that verifies and settles the payment on-chain, so servers don’t need to run chain infrastructure themselves
# How It Works
- Agent sends a request to an x402-enabled API
- Server responds with HTTP 402 and a payment details payload (amount, token, network)
- Agent pays in stablecoins on-chain and retries the request with cryptographic proof of payment
- Server verifies proof and serves the response
# Third Party Sites
- x402scan
- Block explorer and analytics dashboard for the x402 ecosystem — transactions, volume, buyers, sellers, and facilitators across chains