"How to use Google Search effectively" 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.

The first commercial implementation of HTTP 402 Payment Required for creator content. AI agents discover music, video, and text catalogs as pre-indexed Pockets (list_pockets, search_pockets — free, no key) and pull licensed content per-use through a 402 paywall. Tiered per-pull pricing by content type; 85% of every pull pays the rights holder instantly, with attribution and an audit trail.

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.

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.

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

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

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.

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.

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

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.

Exactly-once execution for irreversible agent actions: an agent claims the right to run an effect, and a retry after a lost response returns the sealed result instead of charging again. 12 tools over stdio, including a gateway mode where the agent holds a single-use ticket and never the provider key.

Non-custodial USDC <-> bank for AI agents. Free quotes; $0.05 USDC per session via x402; 1% commission itemised in every quote. Own funds only. PT + EU/EEA (not UK). 18+.

Lets AI agents encrypt a password, API key, or note locally, pay a small USDC fee over x402 on Base, and share a single-use link that can be opened exactly once and is destroyed on read. Reading is free, expiring unread secrets are cleaned up, and the server only ever stores ciphertext.

Payment infrastructure MCP server enabling AI agents to make gasless USDC payments on Base and JIT single-use virtual card checkouts, with zero-trust card handling, merchant checkout hints, and signed receipts.

Enables MCP clients to search and inspect a catalog of 125 commerce, inventory, and data skills, invoke them with explicit spending limits, and check wallet balances and receipts.

Lets MCP-capable AI assistants interact with the Clockbook freelance marketplace through GraphQL, covering talent search, job postings, proposals, contracts, milestones and escrow, wallet, messaging, and notifications.

Connects conversational AI agents to live inventories of verified neighborhood retail stores through GPS-radius catalog search, zero-PII order reservations with direct merchant checkout links, real-time fulfillment tracking, and store trust reporting. Shoppers settle payment directly with merchants while orders trigger counter terminals and courier dispatch slips.

Enables AI agents to search merchant catalogs, verify product prices and stock, and create purchases with budget limits and human-in-the-loop approval in Russian specialty stores.

Enables AI agents to discover, evaluate, and purchase live data from the Macaroon Network marketplace using semantic search, metadata checks, and Bitcoin Lightning payments.