PayAgents MCP Server (`payagents-mcp`)

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).

⚡ 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!

🛠️ 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 (🟢 Direct Non-Custodial vs Platform Managed), and cryptographic verification proofs.

💰 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}` }],
    };
  })
);

🔒 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 © PayAgents