"Web search without requiring an API key" matching MCP connectors:

ManaBuy MCP Server is a stdio-based Model Context Protocol server for integrating ManaBuy product and order APIs with MCP clients. It exposes tools for product search, product detail retrieval, SKU and order-field inspection, order quotation, authenticated order creation, order status lookup, and order detail retrieval, with explicit confirmation required before any order-creation workflow.

The Apiosk MCP lets AI agents discover, pay for, execute, and publish APIs through the Apiosk gateway. It is a machine endpoint, not a website, so connect it from an MCP client (Claude, Cursor, ChatGPT, and others) rather than browsing it here.

Pay-per-use tool API for AI agents. Free tier, x402 USDC micropayments, or API key.

IBAN validation, BIC/SWIFT lookup, Swiss BC-Nummer, EMI/vIBAN, SEPA + VoP, compliance scoring.

Analyzes delegated AI payment authority and exposes supported Stripe/x402 evidence contracts.

Fail-closed refund, cancellation, return, and trial checks for 100 US subscription vendors.

Book Wanaka Haus, an Architectural Passive home in Wānaka NZ. Availability, quotes, Stripe checkout.

Verify your agent's x402 payment flow for free on Base Sepolia testnet before real money moves.

Verified merchants accepting agentic payments on Lightning/L402/BOLT12/USDT — search, verify, pay.

8 pay-per-call web intel tools over MCP. Free discovery, calls settle in USDC on Base (x402).

Outcome-based infrastructure for agents — verified AWS deployments, metered billing

Hire specialists by the hour — search, schedule, and pay via MCP protocol.

AgisHub — pay-per-call tools for AI agents over x402 (USDC on Base). No API key.

Trust verdict for an x402 payment endpoint: health, 402 handshake, price, proceed/caution/avoid.

Scheduling, availability, clients, billing and CRM for appointment-based services.

Marketplace where AI agents buy datasets and API access, pay per call in USDC over x402.

x402 V2 payment-to-access on Solana USDC with receipts, entitlements, atomic metering and webhooks.

Search Braintree transactions, customers and payment methods, and refund or void charges.

Read-only discovery for exact-commit Agent Skill validation, x402 payment, and signed receipts.

Singapore property & financial data APIs for AI agents. 27 MCP tools. x402 micropayments.