x402 MCP Starter

Validate x402 USDC payment configurations for a read-only MCP product on Cloudflare Workers before adding paid tools or deploying.

Use this skill when an MCP product needs a small, x402-aware USDC payment path for a read-only result. Start before deployment, when the operator needs to check the network, USDC asset, price, recipient, and facilitator configuration.

Do not use it to custody wallets, move funds for another party, implement a subscription system, or turn an unvalidated product into a paid service.

Connect

• MCP endpoint: https://x402-mcp-starter.kadopi.workers.dev/mcp
• MCP Service Card: https://x402-mcp-starter.kadopi.workers.dev/.well-known/agent-card.json
• Product page: https://aegis-sales-bot.kadopi.workers.dev/products/x402-mcp-starter
• Source: https://github.com/kadopi/x402-mcp-starter
• MCP Registry search: https://registry.modelcontextprotocol.io/?q=io.github.kadopi%2Fx402-mcp-starter

Free configuration check

Call validate_x402_config before deployment with:

• network: eip155:84532 for Base Sepolia test USDC, or eip155:8453 for Base Mainnet real USDC;
• asset, amount, and priceUsd: the intended canonical USDC asset and matching atomic-unit price;
• payTo: the controlled recipient EVM address;
• facilitatorUrl: the HTTPS facilitator endpoint.

If ready is false, correct only the returned configuration errors. Do not deploy or attempt payment until it is true.

Paid sample boundary

get_paid_sample is a fixed-price reference path, not product revenue. A call that may trigger payment requires the business principal's explicit approval immediately beforehand. Keep buyer keys in the payment client; never provide a private key or payment signature in a prompt, source file, log, or support message.

For a real customer product, replace the sample handler with one defined read-only result and state the price, delivery, retry, and failure behavior before release.

Limits

The public endpoint uses Base Sepolia and test USDC by default. The buyer's private key stays in the payment client. Production Mainnet operation requires the operator's own configuration, deployment approval, and a separately authorized payment decision.