"Building OpenAI Agents SDK Using Official Documentation" matching MCP servers:

Agent Toolkit for Mercado Pago

Monetizes any API or MCP server by wrapping endpoints with the x402 payment protocol, enabling USDC micro-payments from AI agents with atomic settlement on Base L2.

Universal billing gateway for MCP servers. Add Stripe subscription billing to any MCP server with one line of code. Supports tiered plans, usage tracking, and automatic access control.

Enables AI agents to integrate Midtrans payments by providing comprehensive documentation, API references, and code examples for 15+ payment methods across 5 languages. Includes tools for generating charge requests, webhook handlers, and searching documentation without requiring API keys.

Discover and pay for APIs and MCP tools per call over Bitcoin Lightning (L402): search the bolthub marketplace, preview prices, and pay from your own wallet (LND, NWC, LNbits) with hard budgets, prepaid credit, scoped sub-agent delegation, and verifiable receipts. Non-custodial and works without a wallet for search and free tools.

Enables AI agents to autonomously quote, execute, and verify on-chain payments in USDG on Robinhood Chain (chainId 4663) under spending policy caps, alongside live PONS price, launch-token metadata, market, and balance lookups. Payments are signed, broadcast, and only marked confirmed once the on-chain receipt and expected USDG transfer event verify.

eSIM data plans for 200+ countries: search wholesale plans, check balance and usage, diagnose eSIM connectivity from live network data, and (opt-in) order and top up eSIMs with a confirmation step.

Enables AI agents to autonomously quote, execute, and verify USDG payments on Robinhood Chain 4663 under configurable spending caps, while accessing PONS price, token, balance, and launch-market intelligence through MCP tools.

Enables AI agents to manage financial operations including balance checks, money transfers, invoicing, spending policies, and audit logs through the PayGent API.

Enables agents to search, compare, and book hotels across roughly 3 million properties in 200+ countries, paying per booking in USDC on Base via the x402 payment handshake (with a CoinGate fallback) and then polling for order confirmation.

Enables AI agents to synthesize speech via the unlimitedtts API, handling x402 micropayments, spend policy enforcement, and storage of private MP3 results.

Pay-per-call USDC payment proxy for AI agents. Issue scoped Pay Tokens with hard spending caps and auto-journal every charge to freee / Money Forward / QuickBooks.

Provides a three-layer payment firewall for AI agents, enabling identity verification, risk screening, and execution authorization with on-chain policy enforcement for secure and auditable transactions.

Provides AI models with authoritative knowledge and code generation for Kapital Bank's payment gateway, including endpoint specifications, payment flows, code samples in multiple languages, error code lookup, and sandbox test credentials. It enables integration without requiring merchant credentials or live bank execution.

A paid MCP server that lets AI agents send SMS messages to US phone numbers via x402 micropayments, with automatic compliance and opt-out handling.

Enables AI agents to discover and pay for x402-gated HTTP APIs, handling 402 Payment Required flows with local signing. Supports EVM and Solana with non-custodial wallet management.

MCP server for the Gravv payments API that lets AI assistants onboard customers, run KYC, open accounts, move money, issue cards, and exchange currency, with built-in documentation search and safety confirmations for money-moving operations.

Enables AI agents to create and manage sellable listings, handle orders, and integrate Stripe payments through natural language using ListBee's API.

Official Dodo Payments MCP servers - dodopayments-api for live payments, subscriptions, customers, products, refunds, license keys, and usage-based billing (browser OAuth, no API key needed) and dodo-knowledge for semantic search over Dodo Payments documentation.

x402-trust gives AI agents a "check before you pay" layer for the x402 ecosystem.