{"success":true,"url":"https://x402.org","final_url":"https://x402.org/","markdown":"# x402 Protocol\n\nThe x402 protocol enables pay-per-request APIs using the HTTP 402 Payment Required status code and USDC stablecoin payments on the Base blockchain.\n\n## How It Works\n\nWhen a client calls an x402-protected API without payment, the server returns HTTP 402 with a payment payload. The client's x402-enabled wallet automatically pays the requested amount in USDC and retries the request — all within a single API call.\n\n## Key Features\n\n- **Zero integration friction**: AI agents discover and pay for APIs automatically\n- **USDC on Base**: stable, fast, and cheap settlement\n- **Open standard**: any HTTP client can implement the x402 payment flow\n- **Per-request pricing**: pay only for what you use, no subscriptions\n\n## Network Support\n\nThe x402 protocol currently supports Base mainnet and Base Sepolia testnet. Mainnet uses production USDC; Sepolia uses test USDC for development.\n\n## Developer Resources\n\nThe x402 ecosystem includes SDKs for JavaScript/TypeScript (npm: `x402-js`) and Python (pip: `fastapi-x402`). Server implementations are available for FastAPI, Express, and Next.js.\n\n## Getting Started\n\nTo use an x402 API: install the x402 client library, configure your wallet private key, and call any x402-protected endpoint. The payment flow is fully automated.\n\nTo build an x402 API: add `fastapi-x402` to your FastAPI app with `init_x402(app)` and decorate your endpoints with `@pay(\"$0.01\")`.","links":[{"url":"https://x402.org/docs","text":"Documentation"},{"url":"https://github.com/coinbase/x402","text":"GitHub"},{"url":"https://x402.org/quickstart","text":"Quickstart Guide"},{"url":"https://www.npmjs.com/package/x402-js","text":"x402-js on npm"},{"url":"https://pypi.org/project/fastapi-x402/","text":"fastapi-x402 on PyPI"}],"tables":[{"headers":["Network","Token","Status","Chain ID"],"rows":[["Base","USDC","Mainnet","8453"],["Base Sepolia","USDC","Testnet","84532"]]},{"headers":["SDK","Language","Install","Min Version"],"rows":[["x402-js","JavaScript/TypeScript","npm install x402-js","0.1.0"],["fastapi-x402","Python","pip install fastapi-x402","0.1.8"]]}],"images":[{"src":"https://x402.org/logo.png","alt":"x402 logo"},{"src":"https://x402.org/og-image.png","alt":"x402 Protocol — Pay-Per-Request APIs"}],"metadata":{"title":"x402 — Pay-Per-Request API Protocol","description":"The open standard for machine-to-machine micropayments using USDC on Base blockchain","og_title":"x402 Protocol","og_image":"https://x402.org/og-image.png","canonical_url":"https://x402.org/","language":"en","status_code":200,"content_type":"text/html; charset=utf-8","content_language":null,"x_robots_tag":null},"warnings":[]}