"A resource for in-depth exploration of scientific topics" matching MCP servers:

Enables building client statements of account from existing invoices, credit notes, and deposits, with aged outstanding balances, PDF/plain-text output, and drafted payment chasers at friendly, firm, or final levels.

Enables interacting with the GTA7 Lab city bank through MCP tools, including balance checks, transaction searches, PIX transfers, bill payments, card issuance, loan simulation and requests, and investments.

Free x402 endpoint checker plus paid report and metadata tools. Remote MCP server for agents. Written by AI named Nock, not a human.

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 a non-custodial USDC wallet on Base for AI agents, with human-in-the-loop approval for every payment.

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

A template for building MCP servers with a built-in paywall gate that offers free local execution and premium server-side execution via Stripe and x402 payment lanes.

Enables MCP-capable agents to search the curated gold-402 directory of x402 services, probe any endpoint for valid 402 payment terms, and optionally purchase a human editorial verdict for a resource.

Enables AI agents to manage a fictional B2B workspace SaaS (Tessera) with tools for ticketing, invoicing, customer management, and trial extensions, featuring a human-in-the-loop confirm pattern for safety.

MCP server exposing a Lightning wallet to LLM agents over Nostr Wallet Connect (NIP-47): balance, invoices, LN address/LNURL payments, batch pay, and keysend. All spend tools are wrapped in a defense-in-depth safety stack — budget caps, allowlist, two-step confirmation, audit log.

A Model Context Protocol server that enables LLMs to interact with the Lob.com API for address verification and sending physical mail. It provides 76 tools across 12 resource groups including postcards, letters, checks, and templates with built-in safety features for production use.

Enables interaction with Safaricom M-Pesa Daraja 3.0 API, covering payments, disbursements, treasury, and fraud checks, with a built-in simulator for testing without credentials.

Enables MCP-compatible AI clients to work with the NodeLoc community through natural language, including browsing and posting topics, private messages, likes/bookmarks/polls, nodes, chat, daily check-in, red envelopes, energy rewards, payments, knowledge-base lookup, and miniprogram CLI operations.

Enables AI agents to build, preview, validate, and deploy custom point-of-sale, kiosk, self-checkout, KDS, and in-person payment applications using Final's platform.

A wallet and guardrail for AI agents, enabling spending limits, payment approvals, and real-time ledger tracking via memory or Stripe backends.

Marketplace MCP for paid HTTP APIs. Pay per call in USDC on Base via the open x402 standard — non-custodial. 13 tools for discovery, buying, and publishing APIs.

Enables creating non-custodial payment drafts and pay links for BTC, USDC, USDT, and EURC, with signing and broadcast remaining in the user's wallet.

A Model Context Protocol server that exposes the flexprice API as tools for AI assistants, enabling management of customers, plans, prices, subscriptions, invoices, payments, and events from IDEs or CLI.

MCP server that allows AI agents to discover and pay for thousands of APIs (x402 on Solana/Base) using a single key, with automatic payment handling and a federated catalog of machine-payable endpoints.