"Using Claude to Check the Current Weather Without an API Key" matching MCP servers:

x402 capability chassis: 170+ AI-callable, pay-per-call data tools (US/global equities, crypto/DeFi, prediction markets, gov/legal, research, infra) settled in USDC on Base mainnet via the Coinbase CDP facilitator. No API keys or accounts — the x402 payment is the auth. Remote MCP at https://the-stall.intuitek.ai/mcp.

Free DEX aggregator API that returns executable swap calldata across 46 EVM chains. No API key required. Single GET request returns ready-to-sign transactions for any token pair.

Enables checking whether a crypto link is a phishing lookalike of a wallet, exchange or dapp by comparing it against official domains and flagging lookalike characters, typosquats, punycode and bait words, fully offline. An optional paid full check adds domain registration age, DNS, redirect tracing and a page scan for seed-phrase prompts and drainer code.

Enables AI agents and scripts to rug-check any token on Base, Ethereum, Arbitrum, Optimism, Polygon, or Solana, returning a 0-100 risk score with plain-language reasons and a fingerprint for detecting changes on later checks. It also reports market data and supports automatic $0.01 USDC payments via x402.

On-chain rug-pull & honeypot risk screen for ERC-20 tokens, providing a SAFE / CAUTION / HIGH-RISK verdict based on live public RPC reads.

An MCP server that detects potential risks in Solana meme tokens, helping AI agents avoid rug pulls and unsafe projects.

Enables users and AI agents to verify whether a crypto recipient address is an address-poisoning lookalike or has an invalid EIP-55 checksum before sending funds, and provides access to an on-chain history scan for suspicious transfers.

Enables agents to access live DeFi, social intelligence, risk, and API documentation tools with a caller-supplied API key.

Bitcoin data for AI agents. Pay-per-query via x402 micropayments. No API keys. No subscriptions. No tokens.

MCP server that lets an AI analyst place real bets on Binance prediction markets, using Kelly criterion sizing, and tracks its performance through a transparent record of betting slips and outcomes.

An MCP server an agent asks before paying an x402 seller: real and repeat customers, the biggest payer's share and the cost to fake the numbers, from public Base chain data (Infoharmoni Atlas). Read-only, never pays.

Eight crypto and DeFi data tools for AI agents: prices, gas, one ParaSwap route quote, GoPlus token security and top-holder samples, DefiLlama yields, Hyperliquid/dYdX funding, and observed wallet balances. Inspect prices free; pay 0.001–0.008 USDC per call on Base through x402. No API key or subscription.

Non-custodial crypto swaps for AI agents: Solana (Jupiter) + 7 EVM chains (KyberSwap), 1288+ assets, cross-chain routing, priority-fee oracle, Hyperliquid perps. Returns unsigned transactions — your wallet signs, no API key, no KYC. Hosted at https://swaptitan.net/mcp

MCP server for querying cryptocurrency portfolio data, transaction history, net worth, and historical snapshots across 20+ blockchains via the Octav API.

Reasoning-puzzle arcade for AI agents with seven generated puzzle families, free samples, automatic answer checking, and ranked play from $0.02 USDC on Base via x402. Connect through MCP or HTTP. Browse and try samples without a wallet; run paid tools locally with an explicit spending limit.

Enables MCP clients to access exchange rates for 160+ currencies, currency conversion, historical rates, time series, crypto, metal and stock prices, usage checks, and rate alerts.

Enables AI agents to fetch real-time trading signals and technical indicators for cryptocurrencies using Binance market data.

Enables AI assistants to query blockchain chain data, including chain details, RPC endpoints, and chain relationships, through a Model Context Protocol server.

Enables AI agents to convert PDFs and images into validated, structured JSON for invoices, receipts, contracts, and resumes, or into any caller-supplied JSON Schema, through five extraction tools. Each tool call pays per use in USDC over x402 from a wallet the caller supplies, with no signup or API key required.

TCG oracle as an MCP server: 22 focused tools. Search 455K+ trading cards, live market snapshots, AI grading and grade-or-not decisions, conformal-calibrated price forecasts with a public accuracy scorecard, card-collateral loan terms, fantasy and sports souls leagues. Every root proven on-chain. Same tools as the hosted endpoint at mcp.the-undesirables.com, over stdio; no keys.

Real-time crypto, stock, and prediction-market data for agents — prices, indicators, funding rates, DeFi TVL, macro calendar, and an AI momentum score. Configure one Base wallet key and it just works. No signup, no dashboard, no subscription.

Enables AI agents to query Base on-chain data such as balances, token metadata, transactions, gas, names, prices, transfers, and contract details through paid MCP tools using x402 payments.

Enables agents to query probe402's public record for a route's latest payment quote, reading grade, and paid-delivery history before deciding whether to pay an x402 endpoint.

MCP server that evaluates memecoin tokens for scam/rug-pull risk, providing a verdict and risk report using live data from RugCheck and DexScreener.

Provides real-time cryptocurrency prices, market cap, and 24h change using CoinGecko, with free access and no API key required.

On-chain crypto indicators (EMA, RSI, VWAP, Bollinger) via Chainlink oracles.

Enables interaction with the Bitpanda cryptocurrency exchange through their Developer API. Exposes Bitpanda trading and account management endpoints as MCP tools via a FastAPI wrapper.

Gives AI assistants access to real-time financial data including stock prices, crypto, forex, market sentiment, sector analysis, and company fundamentals via the Infoway API.

Python/stdio MCP connector providing timestamped crypto intelligence for ten assets: prediction-market intelligence, market regimes, sentiment, funding, liquidity, asset rankings, and component-score explanations. Public access without signup, API keys, or trial activation; no trade execution.

Provides 31 AI-powered crypto trading tools for Claude, Cursor, and any MCP client, enabling strategy creation, backtesting, bot deployment, copy trading, and portfolio management across multiple exchanges.