Give your AI agents
a Solana wallet

x402-pay is an MCP server that lets AI agents autonomously discover, pay for, and fetch HTTP 402 paywalled resources using Solana. No human in the loop.

View on GitHub Quick start

HTTP 402 + Solana

Agent --> x402_fetch("api.example.com/data") | +--> GET /data | 402 Payment Required | X-Payment-Amount: 1000000 | X-Payment-Token: SOL | +--> Send 0.001 SOL on Solana | tx: 5kR...confirmed | +--> GET /data + X-Payment-Signature | 200 OK + content | Agent <-- { content, receipt }

The gap

AI agents can browse the web. They can't pay for anything.

The "autonomous agent economy" has no payment rail. When an agent hits a paywall, it stops and asks a human.

The problem

AI agents can reason, write code, search the web, and call APIs. But the moment a resource costs money, autonomy ends. The agent stalls, escalates to a human, and waits. Every paid API is a dead end.

0 MCP servers

implement autonomous x402 payments

The solution

x402-pay gives any MCP-compatible agent a Solana wallet. When it encounters HTTP 402, it reads the price from response headers, sends SOL or USDC on-chain, attaches the tx signature, and fetches the content. Under 2 seconds, end to end.

< 2s

discover, pay, and fetch -- fully autonomous

6 tools

Everything an agent needs to operate in a paid internet

Install once, add a keypair, and your agent can pay for anything. Zero config beyond that.

x402_discover

Probe a URL for x402 payment requirements without paying. Returns paywall status, price, token, and recipient address.

read-only

x402_pay

Send a Solana payment to satisfy an x402 paywall. Auto-discovers requirements or accepts manual overrides for amount and recipient.

payment

x402_fetch

One-shot x402 flow: discover paywall, pay on Solana, fetch content. The primary tool for agents -- handles the full handshake.

primary

x402_balance

Check the agent's Solana wallet balances. Returns SOL and USDC holdings so the agent can reason about what it can afford.

read-only

x402_history

Query the local payment ledger. Shows past x402 payments with URLs, amounts, token types, and transaction signatures.

read-only

x402_serve

Register a resource behind an x402 paywall. Makes your agent a seller -- it responds with 402, verifies on-chain payment, then serves content.

seller

Quick start

Add to Claude Desktop in 30 seconds

Works with Claude, Cursor, Windsurf, or any MCP-compatible client.

claude_desktop_config.json

{
  "mcpServers": {
    "x402-pay": {
      "command": "npx",
      "args": ["x402-pay"],
      "env": {
        "SOLANA_KEYPAIR_PATH": "~/.config/solana/id.json",
        "SOLANA_RPC_URL": "https://api.devnet.solana.com"
      }
    }
  }
}

Three steps to autonomous payments

Install with npm install x402-pay or use npx directly -- no global install needed.
Point SOLANA_KEYPAIR_PATH at a funded keypair. Create one with solana-keygen new and airdrop devnet SOL.
Ask your agent to fetch a paid resource. It calls x402_fetch, handles the 402, pays on-chain, and returns the data.

Give your AI agentsa Solana wallet

AI agents can browse the web. They can't pay for anything.

The problem

The solution

Everything an agent needs to operate in a paid internet

Add to Claude Desktop in 30 seconds

Three steps to autonomous payments

75 seconds from idea to payment

Give your AI agents
a Solana wallet