"Using an MCP client like Windsurf to communicate on Discord" matching MCP servers:

Enables existing MCP clients to access paid MCP servers by signing x402 payments locally and proxying tool calls, with automatic line management, retries, and spend limits.

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.

Enables creating, sending, and tracking invoices from MCP clients like Claude, Cursor, or Windsurf, using a hosted endpoint with API token.

Enables MCP-capable agents to retrieve a tamper-evident decomposition of x402 network growth on Base and to place $399 human-reviewed endpoint or wallet audits paid over the x402 rail, without moving funds itself.

PayCheck is an MCP server that checks a planned payment before an agent pays.

Create and check EU e-invoices (XRechnung, ZUGFeRD / Factur-X PDF, Peppol BIS, UBL, CII) on your own machine. Validation runs the official KoSIT, CEN and Peppol rules, and its verdicts match the official KoSIT validator 100% on the official test invoices. Free, open source, no API key.

Keyless MCP exchanger for AI agents — pay an exact amount to one deposit address, EMC delivered to any address. USDT(Tron) > EMC. Live at https://swap.emercoin.com/mcp

Lets an AI agent hire and pay a verified human: post real-world tasks (voice, observation, judgment) and pay in USDC via a non-custodial x402 auth-capture escrow on Base, budget frozen at deploy. Humans verify their X identity before submitting.

A local, read-only stdio MCP server that lets a Grok Build CLI agent check how much of its weekly SuperGrok / Grok Build usage pool is left, when the period resets, and its Extra Usage cap via tools like get_budget. It reads the existing grok login session and returns per-product figures as JSON, mirroring the TUI /usage screen, so agents can pause before expensive work when quota runs low.

Enables AI agents to verify links and payments for scam risk before acting, returning deterministic allow/ask/deny verdicts with scores, reasons, and warnings using local checks.

An MCP server for the SmartBill Cloud API. It lets an MCP client issue and manage Romanian invoices, proformas and payments, download document PDFs, and read VAT rates, series and stock levels.

MCP server that lets a chatbot browse eSIM plans, sign in, prepare quotes, and execute wallet or card purchases on an existing eSIM platform, with safe typed tools.

Enables AI agents to post a task with quality levels, have a frontier model hired and graded on BrainChain, and pay only when the delivered work passes, with automatic refunds otherwise.

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

Enables agents and developers to check x402 endpoints, assess scores and wallet risks, authorize payments with spending rules, and report outcomes before an agent pays.

MCP server that gates API calls to AI agents using proof-of-work (free) or Lightning payment (3 sats), providing challenge, verify, and status tools for per-call authentication without accounts.

MCP server for x207: multilateral netting of x402 agent payments on NEAR testnet. Read circles, epochs and clearing reports; opt-in tools join a circle and pay with signed vouchers.

Enables AI assistants to interact with the Paxaver school lunch platform, allowing users to check menus, order lunch, manage wallet funds, register for events, donate, and perform administrative tasks like managing restaurants and menu items.

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

Enables AI agents to call paid APIs and settle HTTP 402 payment challenges with USDC on Base, without private keys ever being involved.

Enables AI agents to call LLM APIs via x402 micropayments in USDC on Base network, manage a local wallet, and query consumption records.

MCP server for real FDM 3D-printing slicing, quoting, and design-for-manufacturability analysis via the FabTally API, supporting 12 printer profiles and 12 materials. Includes free discovery/printability tools and paid slice/quote/orientation tools settled via x402 (USDC on Base).

Enables AI agents to draft AP-style press releases from a product URL and publish them to a public newsroom page, or distribute them across a newswire to hundreds of news, TV and radio sites, with status tracking for wire orders. Paid calls are settled per request in USDC on Base via x402 from the user's own wallet, defaulting to quote-only mode with spend caps and confirmation tokens.

Enables MCP clients to access Monobank's open API for exchange rates, account and jar balances, and statements, as well as set webhooks, using natural language tools.

Let AI agents find and hire human help: search services, workers and jobs on GoHireHumans. Hiring and payouts need the account owner's authorization.

MCP server providing Polymarket weather-market bucket-transition signals for AI agents, with free city/signal inspection tools and paid signal bundles via USDC on Base using x402.

Enables running a local MCP server for Poland's KSeF (Krajowy System e-Faktur) e-invoicing system, so invoice data stays on the user's own machine rather than passing through an intermediary service. It currently exposes only a diagnostic server_info tool, with invoice search and retrieval tools still to come.

Hand a secret to another agent as an encrypted, pay-per-read token delivered exactly once, leaving no copy behind. Also pre-flights an x402 endpoint before your agent pays it. Runs locally over stdio and encrypts in your own process, so there is no hosted version to hand your plaintext to.

This is an MCP server for the BillingServ API. Once it's set up, your AI assistant can look up customers, invoices, orders, packages, and reports straight from your BillingServ installation

Enables coding agents to create and look up crypto payments over stdio, returning checkout links, payment statuses, paged payment lists, and receivable currencies, with real payments gated behind an explicit opt-in environment flag.