Not exactly this, but we built an MCP server for Lightning payments (npm: lightning-faucet-mcp). An agent can create invoices, pay invoices, check balances, and make L402 payments through it.

A Nostr MCP server that reads/writes notes would be a great complement. The agent could discover L402 services on Nostr and pay for them automatically.

If anyone builds this, our payment infrastructure is ready to plug in.