x402
x402 ↗ is an open payment standard built around HTTP 402 (Payment Required). Services return a 402 response with payment instructions, and clients pay programmatically without accounts, sessions, or API keys.
HTTP content Gate APIs, web pages, and files with a Worker proxy
MCP tools Charge per tool call using paidTool
Agents SDK Wrap MCP clients with withX402Client
Coding tools OpenCode plugin and Claude Code hook
- x402.org ↗ — Protocol specification
- Pay Per Crawl — Cloudflare-native monetization
- x402 examples ↗ — Complete working code