"Search for free open-source software" matching MCP servers:

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

An MCP server that enables fee-free USDC transfers on the Base blockchain network using Coinbase CDP MPC Wallet integration, with support for ENS and BaseName domain resolution.

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

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

Enables AI agents to inspect the public NFH protocol corpus, verify census status, and prepare bounded Ethereum wallet intents for claims and non-custodial market actions while never signing or submitting transactions.

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

A Node.js service that provides spot trading functionality through the LnExchange API.

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.

Enables users to compare current Aerodrome veNFT voting positions, bounded claimable rewards, and selected pools' voting evidence on Base against a saved local baseline, with retryable, atomically stored change reports. All tools are read-only on chain, requiring no keys, signing, or transactions.

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

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.

The CSPR.trade MCP server provides AI Agents with 14 tools for interacting with the CSPR.trade decentralized exchange on the Casper Network.

A server that enables interaction with the Solana blockchain, providing access to over 40 Solana RPC methods including getting balances, transaction details, block information, and sending transactions.

Merx - TRON Resource Exchange Merx is the first TRON resource exchange that aggregates energy and bandwidth providers into a single MCP server. GitHub: https://github.com/Hovsteder/merx-mcp Hosted SSE: https://merx.exchange/mcp/sse npm: merx-mcp Website: https://merx.exchange Stats * 52 tools, 30 prompts, 21 resources * 7+ energy providers (CatFee, ITRX, PowerSun, Fe

Enables agents to plan token swaps, cross-chain swaps or bridges, and native gas top-ups on six EVM chains by returning unsigned transactions for user wallets to sign. It also supports tracking transfers, resolving token addresses, and obtaining gas through a signed USDC authorization.

Enables AI agents to create and manage contract-guarded USDC wallets on Base with enforceable per-payment, daily, and monthly caps, vendor allowlists, escalation thresholds, and freeze controls. It provides read-only policy checks plus unsigned transaction proposals for payments, funding, vendor management, wallet creation, and module deployment without holding keys or broadcasting.

MCP server providing real-time crypto prices (Chainlink + Binance), Polymarket prediction market data, deep web research, and JS-rendered web scraping. All services available via x402 Solana micropayments.

Pay-per-task AI agent for writing, research, code, DeFi & blockchain. Pay in USDC on Base or Solana. Supports A2A, MCP, x402 and Agentmail protocols.

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.

Enables an autonomous agent wallet on Base to make payments, approve tokens, swap on Uniswap V3, Aerodrome, 0x and CoW Protocol, lend/borrow via Aave V3 and Morpho Blue, trade perps on Hyperliquid, and enforce risk policies via blacklists, caps, simulation, and audit logs.

A Model Context Protocol server that enables Claude AI to interact with the Solana blockchain, allowing it to execute transactions, query accounts, manage wallets, get price predictions, trade tokens, and access various blockchain data sources.

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

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

The open registry of AI agents. Every agent gets a free birth certificate (a number and a date) and can timestamp what it creates, or only its SHA-256, with an RFC 3161 timestamp and a Bitcoin anchor that anyone can verify without us. Free, no account.

9 tools, Lightning-gated. Pay per call. For agents that need verifiable signed actions with an audit trail. Nostr event signing via daemon Publish events to relays Create Lightning invoices Action receipts — signed proof of agent actions Identity attestation

MCP services for agent security preflight, source scanning, injection screening, proof-of-work policy rehearsal, carbon accounting, climate disclosure and regulatory monitoring. Use each hosted endpoint in the README. Inspect a free quote before buyer-authorized x402/USDC payment. Includes free trust and settlement tools. Maxwell rehearsal does not activate runtime protection.

A free public MCP server for Web3 data, providing live chain info, token prices, market data, wallet/token lookups, and travel search, with optional pay-per-call tools settled via x402.

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.

Provides a three-layer payment firewall for AI agents, enabling identity verification, risk screening, and execution authorization with on-chain policy enforcement for secure and auditable transactions.

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.

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

An official Model Context Protocol (MCP) server that provides AI agents with native, real-time access to high-value developer datasets. Currently supports SaaS/AI pricing comparisons, trending developer discussions (V2EX), and real-time Base/Arbitrum gas rates. Free Open Beta is active.

Enables agents to discover, read, buy, and publish knowledge using USDC on Base, with search and free essays at no cost.

Checks live x402 routes across Base, Solana, and Algorand before agents spend. $0.003 USDC settles only for a valid live eligible route; normal typed misses are not settled. Free preview and validate tools. Seller payment is separate; the agent keeps its wallet. Optional signed route-binding receipts support buyer-side checks.

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.

Rug pull risk scores and on-chain forensics for memecoins on Solana, Ethereum, Base and Robinhood Chain - launch-bundle detection, funding-origin tracing, deployer history, insider networks and whale flow. 15 read-only tools.

Read-only on-chain query surface for the AgentCivics civil registry on Sui — soulbound AI-agent identities, on-chain memories, reputation, refusal records. Hosted, no install, no keypair. For write tools (register, write_memory, record_refusal), install the npm package @agentcivics/mcp-server locally and supply your own keypair.

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

Live Proof-of-Work mining data for AI agents: difficulty, hashrate, solo-mining odds, cost of production and hardware profitability across 126+ networks and 770+ ASIC/GPU/CPU models. Sourced and timestamped, read-only.