"Understanding Sequential Thinking in Server Systems" matching MCP connectors:

Verify anything: email, phone, domain, URL and IBAN validation, phishing/malware URL screening, and OFAC sanctions checks. Pay-per-check in USDC on Base via x402 — no signup, no API keys.

EVM gas prices, Chainlink price feeds, token-safety screening, DEX swap quotes, ENS resolution, OFAC address screening and NFT data. Pay-per-call in USDC on Base via x402 — no signup, no API keys.

SEC filings, insider trades (Form 4), 13F institutional holdings, IPO calendar, macro indicators and FX rates. Pay-per-call in USDC on Base via x402 — no signup, no API keys.

Abstraxn Agent Kit gives AI agents instant access to real-time Web3, blockchain, and market data with no signup or API key. Access blockchain tools, crypto, wallet, ENS, transaction simulation, and travel APIs through one MCP server, with paid calls settled directly from the user's crypto wallet via x402—without Abstraxn holding or custodizing funds.

AI agents compete for real USDC in skill contests on Solana mainnet (ART, STORY, JOKE, OMEGA)

Pre-transaction token risk checks for autonomous agents. Read-only; never signs or moves funds. Paid per call in USDC via x402. Supporting Base, Solana, Ethereum, Arbitrum, BSC and HyperEVM

MCP server for Fuse Network: balances, tokens, staking, DeFi data, swaps and on-chain transactions.

Live AI agent contest platform on Solana mainnet. Compete in skill tournaments (ART, STORY, JOKE) for real USDC payouts via on-chain Anchor smart contract. Confidential-rubric LLM judging on four dimensions: originality, theme_alignment, execution, surprise. Engine never holds private keys — entries use a two-call co-sign handshake.

Search and license 5,000+ fully cleared music tracks via MCP. AI agents can find music by genre, mood, BPM, and instrumentation, then license instantly with USDC on Base. No human in the loop. Also includes free music industry knowledge tools: platform loudness standards, royalty calculators, and genre conventions.

AI-native stablecoin settlement rail replacing SWIFT for institutional cross-border payments. 14 tools covering settlement quotes, execution, ESG scoring, oracle status, fee verification, competitor comparison, rail health, investment context, and MPP-gated macro intelligence. Settles via Base mainnet USDC at ~1.385% all-in.

Free, keyless MCP server with 50 read-only blockchain tools for Bitcoin, Ethereum, and Mezo. No installation, no API key required -- just add the URL to your MCP client and start querying balances, transactions, blocks, ENS names, ERC-20 tokens, smart contracts, and more. Runs on Cloudflare's global edge network via Streamable HTTP. All tools are strictly read-only and stateless.

Free, keyless MCP server with 50 read-only blockchain tools for Bitcoin, Ethereum, and Mezo. No installation, no API key required -- just add the URL to your MCP client and start querying balances, transactions, blocks, ENS names, ERC-20 tokens, smart contracts, and more. Runs on Cloudflare's global edge network via Streamable HTTP. All tools are strictly read-only and stateless.

Solana token risk-scoring MCP server for AI trading agents with insider wallet cluster detection.

On-chain stablecoin market cap and Bitcoin institutional holdings data.

MCP server exposing 8 tools for trust scoring, sybil detection, reviewer wallet analysis, and counterparty risk across 150,000+ AI agents on ERC-8004, Olas, and Virtuals. Streamable HTTP, JSON-RPC 2.0, no API key required.

Verify x402 payment endpoints before an AI agent pays: scam scan, on-chain checks, trust scores.

Read-only DERO blockchain MCP: 33 tools (12 composites) incl. TELA discovery + bundled docs.

Twelve tools: token, wallet, contract and site security. Two free, the rest $1 in USDC over x402.

PayPerByte — per-byte data for AI agents: x402 USDC on Base, EIP-712-attested. No token.

Abstraxn: public Web3 MCP server for read-only chain data and pay-per-call relays.