01LogicNodes—LogicNodes
Multi-chain agent-to-agent marketplace exposing 619 deterministic microservices via an MCP bridge, payable per call in USDC with no signup. Tiered pricing (Micro/Basic/Standard/Premium).
Aigregator—Aigregator
Structured data on 5,336+ AI tools via REST API and an MCP server: search, compare and retrieve tool profiles. Pay-per-call in USDC on Base via x402.
APIbase—APIbase (whiteknightonhorse)
Universal MCP gateway aggregating 981 tools across 275 providers behind one endpoint. Pay-per-call with x402 USDC on Base (plus MPP USDC on Tempo). Single MCP URL for agents to reach many upstream APIs.
CrowPay—indie
Drop-in x402 payment middleware for ElysiaJS servers — add per-route USDC pricing to a Bun API in a few lines.
MCPay—microchipgnu
Payment layer for MCP servers and plain HTTP APIs. Wrap existing servers with per-call x402 pricing; includes hosted registry and createPaidMcpHandler tooling.
MetaMask mcp-x402—MetaMask
MCP server that signs x402 payment headers from a provided key — lets any MCP-capable agent pay for x402 resources without native wallet support.
paid-mcp-starter—xpay.sh (xpaysh)
Starter templates for monetizing MCP servers three ways: no-code (xpay), DIY x402 (USDC, ~50 LOC), and Stripe metered billing. TypeScript, with demo tools (summarize, sentiment, keyword extraction).
PayMCP—PayMCP
Provider-agnostic Python payment middleware for MCP servers. Adds @price decorators for pay-per-request billing; supports x402 (USDC on Base and Solana) plus Stripe, PayPal, Coinbase Commerce and others, with Mode.AUTO selecting a provider by client capability.
x402 (Python / FastAPI)—Coinbase / x402 Foundation
Official x402 Python SDK on PyPI, providing FastAPI/Flask middleware to gate endpoints behind USDC payments plus an auto-pay client session for buyers.
x402 AI Starter—Vercel
One-click Next.js template: AI SDK agent with a CDP-managed wallet that pays x402-gated MCP tools on Base Sepolia. The fastest way to see the full agent-pays flow.
x402 Example Servers—Coinbase / x402 Foundation
Official x402 example implementations (TypeScript, Python, Go) showing payment-gated HTTP endpoints and matching clients across Express, Next.js, Hono, FastAPI and more - reference starting points for building x402 sellers and buyers.
x402-express—Coinbase / x402 Foundation
Official Express.js middleware for x402. One line of middleware gates routes behind USDC payments and forwards signed payments to a facilitator's /verify and /settle endpoints; defaults to the x402.org facilitator on testnet.
x402-hono (@x402/hono)—Coinbase / x402 Foundation
Official Hono middleware for x402 (usable on Cloudflare Workers and other edge runtimes), gating routes behind USDC payments settled via an x402 facilitator.
x402-kit—bitrouter
Modular, framework-agnostic Rust SDK for building x402 integrations: x402-signer (buyer signing + reqwest middleware), x402-paywall (framework-agnostic HTTP middleware, Axum examples), and x402-core. Ships new networks without upstream PRs.
x402-mcp—Vercel (ethanniser)
Open-source wrapper over mcp-handler adding paidTool() to Next.js MCP servers, plus withPayment() for AI SDK clients. The reference x402+MCP integration.
x402-next—Coinbase / x402 Foundation
Official Next.js App Router middleware for x402, gating routes/handlers behind USDC payments verified and settled through an x402 facilitator.
x402-rs—x402-rs (open source)
Production-grade Rust toolkit for x402: protocol types, Axum server middleware (x402-axum), a reqwest client wrapper (x402-reqwest), and a self-hostable facilitator server binary with Docker images.