"An open-source relational database management system" matching MCP servers:

Enables querying Base Network blockchain data including blocks, transactions, balances, and smart contracts on mainnet and testnet.

Exposes fourteen read-only tools over the HEY Research public API, letting assistants look up Robinhood Chain projects, builders, shipped work, relationships and market context, with each answer tagged FACT, DERIVED or UNKNOWN and unmeasured fields omitted rather than zeroed. Runs over stdio or hosted Streamable HTTP, and gives no trade instructions.

Enables AI agents to securely use Open Agent ID credentials for signing requests, looking up agent data, and exchanging encrypted messages. It performs all cryptographic operations within the server process to ensure private keys are never exposed to the AI agent.

An MCP server that provides authorization middleware for AI agents using private data, enabling consent management on Aleo and local private inference with persistent policy storage.

An AI-driven platform for analyzing Polymarket prediction markets using on-chain data, offering smart money tracking, sentiment analysis, and arbitrage detection via natural language queries.

MCP server for Pi Network that enables AI agents to query Pi chain data (balances, transactions) and verify user tokens, with optional payment sending that is off by default.

Non-custodial x402 MCP payment layer for AI agents — the open-source alternative to Vercel x402-mcp

23 tools for AI agents working with Nostr Open source. No API key. No account. NIP-46 remote signing Publish notes, reply, react, repost Encrypted DMs (NIP-04 + NIP-44) Fetch events, profiles, social graph

An MCP server that records consented, attributed, paid-for receipts for open-source dependencies, settling per-call USDC payments on Algorand with on-chain attribution.

An open-source, zero-dependency Model Context Protocol (MCP) server and HTTP 402 payment gateway template built for Cloudflare Workers and Node.js. This repository provides an automated store API on Solana (USDC) alongside a native MCP Server interface. It enables AI agents (Claude Desktop, Cursor, etc.) to discover, pay for, and consume paid digital assets via standardized MCP Tools.

Enables AI agents to interact with the AI Network blockchain by managing accounts, submitting transactions, and reading database values. It supports registering Hyper Agents and accessing a Layer 2 DAG-based shared agent memory system based on staking status.

Provides complete HTTP/JSON access to all 100+ Emercoin RPC endpoints with integrated formatting utilities. Enables blockchain operations, name system management, wallet functions, and mining operations through a comprehensive REST API interface.

An MCP server that classifies Polymarket wallets as human or bot, scores their trading edge from 0–10, and streams current open positions.

An open-source, zero-dependency Model Context Protocol (MCP) server and HTTP 402 payment gateway built for Cloudflare Workers and Node.js. This project enables AI agents (Claude Desktop, Cursor, etc.) to natively discover, negotiate, and autonomously pay for digital resources over Solana USDC using standardized MCP tools and standard HTTP 402 Payment Required headers.

Enables searching and retrieving live Solana bounties from Superteam Earn, including full bounty details and currently open feeds, without requiring an API key.

Enables querying Polymarket prediction market data, including top active markets and order books, without an API key or database.

CheapestInference — unlimited flat-rate API for frontier open-source LLMs

An MCP server that gives autonomous coding agents deterministic, schema-validated tools for EVM smart contract development — security scanning, gas profiling, compiler diagnostics, and transaction simulation.

Enables AI agents to read and bid on a paid message slot on Solana, with enforced spend limits, dry-run proposals, and an append-only audit log for every write.

Agent-Level Transaction Safety Oracle. Before an AI agent signs a blockchain transaction, it returns a SAFE/UNSAFE verdict with a SENTINEL Score (AAA-D) and risk flags. Pay-per-call $0.005 USDC via x402 on Base.