Programmable crypto payments built for AI agents and APIs.

Turn any LLM endpoint, MCP server, or autonomous workflow into a monetized service using HTTP 402 paywalls, ES256 wallet entitlements, and policy-guarded USDT/USDC rails.

Start AI agent billing Explore HTTP 402 Kit

21 Tools

Official MCP Server

7+

Low-gas rails

ES256

JWKS license tokens

0.5%

Gateway fee

Short answer

XPayr enables AI platforms and developer-tool builders to accept per-session stablecoin payments, verify ES256 wallet-bound API licenses offline via JWKS, and automate agentic checkout through our official 21-tool MCP server (@xpayr/mcp-server) at a flat 0.5% fee.

Agentic Commerce Stack

Built for machine-to-machine and developer billing.

Combine HTTP 402 challenge headers, remote JSON-RPC MCP tools, and deterministic spending limits without custodial lock-in.

21-Tool Official MCP Server

Connect Claude, Cursor, VS Code, or custom agents to POST https://xpayr.com/api/mcp or @xpayr/mcp-server on NPM.

HTTP 402 & ES256 License Kit

Gate premium API routes with HTTP 402 Payment Required headers and stateless ES256 JWT tokens verified via /.well-known/jwks.json.

Autonomous Spending Guardrails

Enforce per-transaction caps, 24h budgets, chain whitelists, and human-in-the-loop approval thresholds.

99.5% Direct Treasury Settlement

Receive USDC and USDT directly into your multisig or hardware wallet across Base, Solana, Arbitrum, TRON, and Circle Arc.

3-step flow

Gate your endpoint.
Settle USDC per session.

Ship global developer and agent monetization without card minimums or chargeback fraud.

1

Connect wallet & API key

Register on Testnet, configure your settlement wallet, and test tools in /tools/mcp-playground.

2

Add HTTP 402 or checkout flow

Return an XPayr payment session or ES256 License Kit challenge when unauthenticated requests hit your API.

3

Verify & unlock in milliseconds

Validate HMAC-SHA256 webhooks or ES256 signatures locally and provision API credits immediately.

FAQ

Questions about AI agent & API crypto monetization

How AI startups and MCP builders deploy XPayr in production.

Yes. @xpayr/mcp-server (v1.0.0) is published on NPM, GHCR Docker, and the Official Anthropic MCP Registry (io.github.xpayrcom/xpayr-mcp-server), alongside zero-install remote HTTP JSON-RPC at https://xpayr.com/api/mcp.

Configure per-tx caps, daily budgets, and auto-approval thresholds in Agent Commerce Mode, and test your rules first in /tools/ai-agent-policy-simulator.

Yes. Buyers in 180+ countries can pay with Base USDC, Solana USDC, Arbitrum USDT, or TRON TRC-20 USDT with zero FX markup and zero card declines.

XPayr charges a flat 0.5% (50 bps) gateway fee per confirmed payment with $0 monthly minimums.

AI Agent Commerce & MCP Automation

Automate Crypto Checkout with AI Agents, Remote MCP & OpenAPI 3.1.0

Connect Claude Desktop, Cursor, Windsurf, ChatGPT Actions, or custom backend agents directly to XPayr using our 21-tool Model Context Protocol server (@xpayr/mcp-server) or zero-install Remote JSON-RPC 2.0 endpoint (https://xpayr.com/api/mcp). Create payment sessions, verify TxIDs across EVM, TRON, and Solana, and reconcile webhooks with a flat 0.5% gateway fee and 100% non-custodial wallet settlement.

⚡ Zero-Install Remote MCP POST https://xpayr.com/api/mcp

Direct JSON-RPC 2.0 tool invocation for xpayr_create_payment_session and xpayr_calculate_gateway_fee.

📦 Official NPM & SDKs npx -y @xpayr/mcp-server

Published on npm alongside @xpayr/node-sdk@0.2.0, @xpayr/extension-kit@0.2.0, and @xpayr/payment-evidence@0.2.0.

Monetize your AI agents, APIs, and MCP tools globally.

Test live JSON-RPC calls in the MCP Playground or launch a free Testnet merchant workspace.

Create merchant account Talk to engineering