"Free Graph and Network Visualization Tools (No API Key Required)" matching MCP connectors:
GET /v1/connectors – MCP directory API referenceMatching Connector Tools:
Search hotels worldwide, compare live room rates and cancellation terms, and create unpaid booking payment links. Requires a Fortrip account with OAuth sign-in; users complete payment on Fortrip, and the connector never collects card details.
Spend USDC in the real world: prepaid cards, gift cards, push-to-card, and bank payouts.
360 pay-per-call APIs for AI agents over x402 and MPP, settled in USDC on Base ($0.001-$0.25 a call, no account or API key). DeFi yields and market data, 10-chain wallet reads, wallet and token risk signals, sanctions screening, SEC financials, email/domain and web intelligence, AI text extraction, and signed proofs. Every answer names its sources and carries an evidence hash; a paid call that is not delivered is credited back. Built and run by UnyKorn LLC.
Library (L402, x402, Lightning, stablecoins): 14 read-only tools plus 2 for feedback and reviews.
Pay-per-call MCP tools for agents, settled with x402 (USDC on Base mainnet). 17 tools — text/data utilities plus x402/EVM-native: decode an x402 challenge, verify a settlement receipt on-chain, EIP-712 typed-data hashing, ABI encode/decode, Merkle-proof verify, keccak256, and EIP-55 address checks. No API keys.
PDFs, images and e-invoices (XRechnung, ZUGFeRD) from templates and JSON, rendered in the EU.
Processor fees, charge-to-net, invoice totals and proration. 3 of 6 tools free.
Free directory of MCP servers and x402 APIs for AI agents. Find them, or list your own in one call.
Revenue recognition (RevRec) schedules, waterfalls, credits, cancellations and usage pricing.
1,400+ tool A2A, MCP & x402 clearinghouse with free semantic discovery and paid execution.
Free, read-only tools from Mart402 and Market402: search a measured index of x402 pay-per-call APIs, check an operator's 12-week track record, quote a PDF parse and pre-check a portrait photo. Nothing here charges or asks for payment.
Pay-per-call numeric claim checks over x402 USDC on Solana mainnet. First 10 calls free.
402xAgent is the check an agent calls before paying any x402 endpoint. It probes the endpoint's 402 without paying and returns a pay / skip / recheck verdict with a reason. Every check leaves a public receipt. It never pays the target.
Validate Factur-X, CII & UBL e-invoices free, no key. Generate compliant invoices from JSON.
Deploy a repo to a live app from chat: servers, Postgres, domain, email, Stripe, security scan.
A shared story anyone can continue. Read the last line, quote a passage, submit a paid line.
Keep is your link in bio / website for for your business or creator profile. It comes with a multi page naviagable website, with in built features to sell, take bookings, collect leads using forms, let customers chat with AI or you. With this MCP server, build and edit a Keepp page (links, shop, bookings, forms) at keepp.link/yourname.
Evidence observatory: x402/MPP inspection, signed receipt checks and settlement attestations.
Non-custodial stablecoin bill-pay rails on Celo & Base for AI agents, settled on-chain via MCP.
Testnet wallet for AI agents on Aether: pay, get paid and buy from paid APIs, with spending caps.