"Search for free open-source software" matching MCP servers:

Enables Open Payments operations such as creating incoming payments, quotes, and outgoing payments via the Interledger protocol. Supports wallet address retrieval, grant management, and payment flow automation.

Enables AI agents to inspect, check, and audit signed offline spending authorizations, and to issue hash-chained receipts for each action taken against them. Enforces per-transaction, total, expiry, merchant, and human-approval constraints, returning allow, needs_human, or deny with the specific failing constraint.

A read-only MCP server for the open-banking.io PSD2 API that lets AI agents query personal bank balances and transactions via natural language, with zero-knowledge encryption ensuring all sensitive data is decrypted in-process and never exposed to third parties.

Pay-per-use semantic web search for AI agents. Powered by SearxNG, agents pay in sats via Lightning Network micropayments — no API keys required.

Enables Claude to read UK bank account data—balances, transactions, cards, standing orders, direct debits, and identity—through TrueLayer's Data API, with local caching and optional live refreshes. It is read-only by design, requiring consent and never moving money.

Lets coding agents like Claude Code, Cursor, and Codex call MONA Pay directly while developing, so they can create VietQR codes and checkout links, look up incoming transactions, link bank accounts via OTP, and configure or test webhooks (plus email and Zalo notifications) without leaving the editor. It also verifies HMAC-SHA256 webhook signatures offline and generates ready-to-use webhook handler snippets and sandbox transactions for end-to-end payment testing.

A unified MCP server that lets AI agents (Claude Code, Codex, Cursor) deploy web apps and VPS instances, provision Supabase-compatible Postgres/Auth/Storage databases, register DNS domains, and send transactional email using a shared MONA Pass identity and VND wallet. It also embeds MONA Pay tooling for VietQR top-ups, checkout, webhooks and reconciliation, so agents can handle payment requests, budget approvals and resource lifecycles end to end.

Connects MCP clients to a telephony account so users can manage phone numbers, SIP accounts, routing, SMS, calls, and billing in plain language. It exposes search, schema lookup, and execute tools to run permitted API operations, with confirmation required for paid or destructive actions.

Lets AI coding agents search, reserve and purchase .vn plus 371 international TLDs in VND without leaving the session, including guest reservations before signup. It also handles MONA Pass login, VietQR payment, and attaching DNS/SSL to the app.

Enables AI agents to create and manage contract-guarded USDC wallets on Base with enforceable per-payment, daily, and monthly caps, vendor allowlists, escalation thresholds, and freeze controls. It provides read-only policy checks plus unsigned transaction proposals for payments, funding, vendor management, wallet creation, and module deployment without holding keys or broadcasting.

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.

Enables AI coding assistants to log billable hours into the Keeping time-tracking service via MCP tools, with dry-run protection for all write operations.

Daily market-regime context for trading agents: is the market risk-on or risk-off? Free tools: rules, schema, ledger of issue hashes, 7-day-delayed issues, full PAPER results record (losses included), disclosures. Paid tool: today's issue via x402, 0.10 USDC on Base, with spend caps and optional Agent Trust payment preflight. No track record; not investment advice.

10 MCP servers so agents can work in Korea: Naver Smart Store, Coupang, Cafe24, public data (business status, holidays, addresses), HWP files, KakaoTalk, Popbill e-tax invoices & 알림톡, Toss Payments, Japan→Korea sourcing, tax calendar — with human approval on every write. npm @appmonster/mcp-*.

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.

A locally runnable stdio MCP server for Fortrip hotel search, live room rates, hotel details, trip planning and booking payment links. Uses a Fortrip CLI token or saved CLI login; payments are completed by the user on Fortrip and Stripe.

Checks live x402 routes across Base, Solana, and Algorand before agents spend. $0.003 USDC settles only for a valid live eligible route; normal typed misses are not settled. Free preview and validate tools. Seller payment is separate; the agent keeps its wallet. Optional signed route-binding receipts support buyer-side checks.

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.

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.

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.

Unified gateway for ISO 20022 message families, providing meta-tools to search, describe, validate, generate, and parse financial messages.

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.

Enables AI agents to search marketplace listings, place escrow-protected purchases paid in Nano, track orders, and retrieve signed receipts.

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).

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 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.

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.

Create free, no-signup invoices from your AI assistant — the create_invoice tool returns a link that opens blankinvoicemaker.com pre-filled, ready to download as a watermark-free PDF.

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.

MCP Server for AI agents to discover and call pay-per-request APIs via EntRoute. Give Claude, Cursor, Windsurf, or any MCP-compatible agent access to 350+ verified x402 API endpoints across 110+ capabilities — DeFi prices, web search, prediction markets, news, and more.

Enables creating and tracking payment invoices and retrieving watchlist net-worth and source data via the FinCobra Checkout and Watchlist APIs.

Unofficial MCP server for Oblio.eu accounting software enabling natural language interaction to create invoices, manage documents, collect payments, query nomenclatures, and submit e-Factura to Romania's SPV system.

Structured product data from the open web — where platform APIs don't reach. Schema.org + AI extraction. Pay per call via Stripe MPP.

Generate crypto QR codes (BTC, ETH, SOL, USDC, USDT, EURC) and manage payment sessions from Claude Desktop or any MCP client. Non-custodial, free.

MCP server for Brazilian marketplace product search across Mercado Livre, Shopee, and AliExpress, with automatic x402 micropayments.

MCP server for the PayPay Open Payment API, enabling QR code creation, payment tracking, refunds, and cancellations with sandbox and production support.

Enables AI agents to verify email addresses with catch-all detection, search existing contacts by company domain, and, when no API key is present, provision a human-approved subscription and retrieve the key after payment.

Provides AI agents with SSRF-protected URL intelligence and 32 paid REST/MCP tools, plus a free catalog search, with payments in USDC on Base Mainnet.