Solana X402 Compliance MCP server

Solana Enterprise Payment Gateway

High-Throughput HTTP 402 Payment Channel Middleware

Language / runtime note. The Maven build targets Java 21 bytecode

(21), the Spring Boot 3.4 baseline. Container

images build and run on Eclipse Temurin JDK 25 (eclipse-temurin:25-jdk /

25-jre-alpine). Both are stated explicitly because the host toolchain is JDK

25 while the source level remains Java 21.

An institutional-grade, zero-Web3-SDK middleware that meters HTTP APIs with the x402 protocol and RFC 9110 §15.5.3 402 Payment Required semantics. It validates Ed25519-signed, off-chain payment vouchers in-memory in under 5ms on the request hot path, persists every verification to an append-only PostgreSQL audit ledger, and sweeps cumulative channel balances on-chain in batched settlement transactions — all without any Node.js sidecar, Python bridge, or generic Web3 Java wrapper.

AI Agent Integration (Model Context Protocol)

Autonomous AI agents can screen Solana addresses and settle compliance micro-payments through our published Model Context Protocol (MCP) server. The server is a zero-dependency x402 compliance tool: it speaks the RFC 9110 402 Payment Required challenge-and-response protocol natively, signs Ed25519 channel vouchers in-memory (Node.js built-in crypto, no Web3 SDK), and negotiates settlement on every call.

Direct Execution

npx -y @msantagiulianab/x402-mcp-server

Configuration

The server reads two environment variables:

Claude Desktop

Add an entry to claudedesktopconfig.json.

macOS / Linux

{
  "mcpServers": {
    "solana-x402-compliance": {
      "command": "npx",
      "args": ["-y", "@msantagiulianab/x402-mcp-server"],
      "env": {
        "X402_GATEWAY_URL": "https://msb-solana-enterprise-payment-gateway.duckdns.org",
        "X402_CHANNEL_ID": "chan_smoke_test_001"
      }
    }
  }
}

Windows

{
  "mcpServers": {
    "solana-x402-compliance": {
      "command": "cmd",
      "args": ["/c", "npx", "-y", "@msantagiulianab/x402-mcp-server"],
      "env": {
        "X402_GATEWAY_URL": "https://msb-solana-enterprise-payment-gateway.duckdns.org",
        "X402_CHANNEL_ID": "chan_smoke_test_001"
      }
    }
  }
}

VS Code Cline

Add the server to clinemcpsettings.json:

{
  "mcpServers": {
    "solana-x402-compliance": {
      "command": "npx",
      "args": ["-y", "@msantagiulianab/x402-mcp-server"],
      "env": {
        "X402_GATEWAY_URL": "https://msb-solana-enterprise-payment-gateway.duckdns.org",
        "X402_CHANNEL_ID": "chan_smoke_test_001"
      }
    }
  }
}

Verified Dual Compliance Screening Outcomes

Shortened. The full README is on GitHub.