"Search functionality without API key requirement" matching MCP servers:

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

Provides current weather conditions and 7-day forecasts for any location worldwide, covering temperature, humidity, wind, and precipitation, with pay-per-call micropayments via x402.

MCP Server for the LINE Shopping API, enabling AI agents and tools to interact with LINE Shopping data and operations via the Model Context Protocol.

A comprehensive Model Context Protocol (MCP) server that provides complete access to the Recharge Storefront API endpoints. Enables AI assistants to manage subscriptions, customers, orders, and billing through a standardized interface.

An MCP server for Nexi POS payment operations, enabling creation of purchases and refunds, polling payment states, confirming transactions, and recovering unconfirmed transactions.

Connects AI assistants to Quaderno's tax compliance engine, enabling tax calculation, tax ID validation, and invoice creation via natural language.

MCP server that gates premium features behind a combined x402 (USDC per call) and Stripe API key paywall, ensuring only paying users access deep functionality while free tier runs locally.

Enables MCP clients such as Claude Desktop and Cursor to obtain Base L2 payment instructions and extract clean, token-estimated Markdown from web pages after on-chain verification of a 0.05 USDC payment.

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.

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

Reads and validates any European e-invoice a business receives — XRechnung, UBL, CII, ZUGFeRD/Factur-X PDF, Peppol BIS 3, FatturaPA, KSeF FA(3) — into canonical EN 16931 JSON with plain-language fix hints in EN/DE/PL/IT/FR, plus PDF, CSV and DATEV export. Nothing is stored; works without a key on a small daily quota.

Keyless crypto payments for AI agents. One MCP call turns any wallet address into a non-custodial crypto payment link or tip jar, no API key and no account, with funds settling straight to your wallet at a 0% platform fee (USDC/USDT, BTC, LTC, DASH, DOGE, ZCASH).

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.

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.

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.

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.

MCP server for Tersign, the evidence layer for agent commerce, enabling agents to issue, verify, and manage signed receipts, compliance records, refunds, and disputes on a counter-signed hash-chained ledger.

MCP server that gives AI agents paid tools to de-risk costly actions: dependency vetting, x402 endpoint verification, JSON repair, and URL reading. Fronts the Guard HTTP API at guard.fabtally.com.

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.