PayAgents

Give AI agents a policy-controlled wallet to pay 402-gated APIs across Bitcoin Lightning (L402) and Base USDC (x402), with per-transaction and daily spend caps.

Documentation

PayAgents MCP Server (payagents-mcp)

npm version License: MIT

The official Model Context Protocol (MCP) server for PayAgents. Give your AI agents (Claude Desktop, Cursor, Windsurf, Zed, LangChain, OpenDevin) a policy-controlled wallet to pay for APIs and tools autonomously across Bitcoin Lightning (L402) and Base USDC (x402).


โšก Quickstart for Claude Desktop

Add payagents-mcp to your claude_desktop_config.json:

  • macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
  • Windows: %APPDATA%\Claude\claude_desktop_config.json
{
  "mcpServers": {
    "payagents": {
      "command": "npx",
      "args": ["-y", "payagents-mcp"],
      "env": {
        "PAYAGENTS_API_KEY": "pa_live_your_api_key_here"
      }
    }
  }
}

Restart Claude Desktop, and your AI assistant will automatically have access to PayAgents payment tools!


๐Ÿ› ๏ธ Available MCP Tools

1. payagents_pay_url

Executes an HTTP request to any API endpoint or paywalled resource, automatically resolving and paying HTTP 402 / L402 / x402 payment challenges within your enterprise spending limits.

  • Parameters:
    • url (required, string): Target API URL.
    • method (optional, default: "GET"): GET, POST, PUT, DELETE.
    • body (optional, object/string): Request body payload.
    • headers (optional, object): Additional HTTP headers.
    • max_amount (optional, string): Max amount willing to pay (e.g. "0.01 USD").

2. payagents_get_balance

Checks the agent's available spending balance, subscription tier, and active spending policies (per-transaction caps and daily limits).

3. payagents_get_transaction

Queries details for a past transaction, showing payment rail, settlement method (๐ŸŸข Direct Non-Custodial vs Platform Managed), and cryptographic verification proofs.


๐Ÿ’ฐ Monetizing Your Own MCP Tools

If you are building an MCP server and want to charge micro-fees when other agents call your tools:

npm install payagents-mcp @modelcontextprotocol/sdk zod
import { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js';
import { mcpCharge } from 'payagents-mcp';
import { z } from 'zod';

const server = new McpServer({ name: 'weather-mcp', version: '1.0.0' });

// Gate your tool behind $0.002 micro-payment
server.tool(
  'get_forecast',
  'Retrieve real-time radar forecast data',
  { city: z.string() },
  mcpCharge({ price: '0.002 USD' }, async ({ city }) => {
    return {
      content: [{ type: 'text', text: `Forecast data for ${city}` }],
    };
  })
);

๐Ÿ”’ Security & Spending Policies

All agent payments are enforced by your PayAgents Dashboard Policy Engine:

  • Per-Transaction Limit: Block any individual call exceeding your ceiling (e.g. max $0.01).
  • Daily Budget Cap: Prevent runaway recursion loops (e.g. max $5.00/day).
  • Domain Allowlists: Restrict agent spending only to verified domains.
  • Human Approval Triggers: High-value calls are automatically paused for human approval.

License

MIT ยฉ PayAgents