"Free and open-source coding assistants" matching MCP servers:

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.

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.

MCP server for Chainlink Runtime Environment, enabling build, simulate, deploy, and manage CRE workflows from any MCP client.

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.

Provides read-only access to public referral deals and codes, races and leaderboards, DeFi interface restriction data, x402 catalogs, cp0x facts, and open-source repository listings. Supports natural-language queries such as finding deals for a venue or checking interface restrictions by country.

Enables AI coding assistants and trading bots to verify smart contracts, test honeypot traps, assess DEX liquidity, and check wallet counterparty risk before deploying or trading capital on Base. It exposes preflight clearance, token audits, KYA reputation, and web-scraping tools with free and paid x402 tiers.

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.

Enables AI coding assistants to estimate session energy footprint and retire verified ecocredits on Regen Network, providing on-chain proof of regenerative contribution.

Free MCP server for x402toll.com, enabling AI agents to discover and use verified, pay-per-call calculators with free previews and hash verification, supporting payments via x402 protocol on Base.

Simulates EVM transactions against forked chain state and explains why they revert, using Tenderly's free-tier API with decoded traces and source-mapped errors. Provides tools to simulate single transactions or bundles and inspect saved simulations, all with output size controls to keep responses affordable.

Enables deep cryptocurrency token research by pulling live market data, exchange listings, protocol TVL and fees from CoinGecko, CoinMarketCap and DeFiLlama alongside web searches. It assembles the results into structured, source-tracked reports covering technical fundamentals, market metrics and social sentiment, free of API keys and fully locally.

Enables local, API-key-free research on any crypto token by pulling live market data, exchange listings, and protocol metrics from CoinGecko and DeFiLlama alongside general web search. It builds structured, multi-source reports covering technical fundamentals, market data, and social sentiment, saving findings as referenceable resources while tracking research progress.

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.

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.

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.

Exposes nine purpose-built tools for EVE: Frontier on Sui Move, covering Smart Assembly contract coding, Smart Gate route and toll planning, Network Node gigajoule optimization, Smart Turret targeting, killmail threat intel, SSU market making, zkLogin character verification, sovereignty fuel tracking, and PTB drain simulation.

Enables LLMs to interact with the AT Protocol ecosystem, including Bluesky, through natural language. Supports public data access without authentication and full write operations with authentication.

Trust infrastructure for AI agents on Base. DEX Spread Oracle (live Uniswap V3 prices), on-chain escrow, insurance pool, and collective knowledge base. 7 smart contracts. Pay-per-query via x402 micropayments in USDC.