"DuckDuckGo Search Engine" matching MCP servers:

MCP server that lets AI agents search the substreams.dev package registry.

Complete DeFi intelligence — Yield, Staking, Restaking, RWA, Perps, Gas Optimization & Contract Security. One answer, not raw data.

Read-only MCP server for discovering and ranking on-chain agents on Stellar mainnet via natural language search, reputation probes, and profile lookups.

This MCP wraps Bitrefill public API to allow agents to search for products and shop using cryptocurrencies like Bitcoin, Ethereum, Solana, and many more.

Pay-per-use semantic web search for AI agents. Powered by SearxNG, agents pay in sats via Lightning Network micropayments — no API keys required.

Provides AI agents with 200 deterministic micro-services covering code auditing, 3D/robotics, media processing, cryptography, blockchain settlement, AI safety, networking, and math, with automatic x402 USDC micropayments.

Provides read-only tools to query live Polymarket prediction-market data via the public Gamma API, enabling search, browsing, and detailed market and event information.

Enables agents to search and inspect live service offerings, generate x402 payment snippets, and understand blockchain-only balance policies.

Connects AI assistants to Solodit's 49,000+ blockchain vulnerability database, enabling search, browse, and lookup of audit findings directly from your AI workflow.

Prediction-market MCP server for Kalshi and Polymarket: market search, live order books and quotes, each venue's fee schedule, fee-aware no-arbitrage checks across related event contracts, and paper orders that walk the book.

MCP server for the CortexCloud API, enabling pay-per-call AI generation, web search, market data, and blockchain RPC endpoints via the x402 protocol, billed in USDC on Base without API keys or subscriptions.

Per-transaction crypto trade validator for AI agents, validates trades with PROCEED/CAUTION/BLOCK verdicts, scans tokens for anomalies, detects rug pulls, and searches across DEXes. Powered by WaveGuard physics engine with deterministic PDE-based analysis.

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.

Deterministic risk governance for crypto trading agents. 5-level policy engine with position sizing, leverage limits, and trade blocking. One tool: get_risk_policy. Supports BTC and ETH.

Provides local access to Aztec documentation, examples, and source code via cloned repositories, with optional semantic search for enhanced querying.

A self-hosted decision engine that sits between an AI agent and blockchain execution. Agents submit a proposed action, Guardian returns an explainable ALLOW / WARN / BLOCK before anything gets signed or broadcast.

A read-only MCP server exposing Polymarket's public prediction-market data. Search markets, read live odds and order books, pull historical probability time-series, and inspect public wallet positions.

MCP server for Polymarket prediction markets, enabling search, market details, pricing, and bet analysis through 6 tools, with optional authenticated trading via API key.

On-chain TCG price oracle for the LitecoinVM ecosystem. 6 tools: search 433K+ trading cards, 60-day price history, Merkle proof verification on LiteForge (Chain 4441), Monte Carlo simulation, and AI card grading via Qwen 2.5 VL.

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