Blockchain MCP Server

import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js"; import { z } from "zod"; import { ethers } from "ethers"; interface ChainConfig { name: string; chainId: number; rpcUrl: string; symbol: string; explorerUrl?: string; } const DEFAULT_CHAINS: Record<string, ChainConfig> = { ethereum: { name: "Ethereum Mainnet", chainId: 1, rpcUrl: "https://rpc.ankr.com/eth", symbol: "ETH", explorerUrl: "https://etherscan.io" }, polygon: { name: "Polygon", chainId: 137, rpcUrl: "https://rpc.ankr.com/polygon", symbol: "MATIC", explorerUrl: "https://polygonscan.com" }, bsc: { name: "BSC", chainId: 56, rpcUrl: "https://rpc.ankr.com/bsc", symbol: "BNB", explorerUrl: "https://bscscan.com" }, arbitrum: { name: "Arbitrum One", chainId: 42161, rpcUrl: "https://rpc.ankr.com/arbitrum", symbol: "ETH", explorerUrl: "https://arbiscan.io" }, optimism: { name: "Optimism", chainId: 10, rpcUrl: "https://rpc.ankr.com/optimism", symbol: "ETH", explorerUrl: "https://optimistic.etherscan.io" }, avalanche: { name: "Avalanche C-Chain", chainId: 43114, rpcUrl: "https://rpc.ankr.com/avalanche", symbol: "AVAX", explorerUrl: "https://snowtrace.io" }, fantom: { name: "Fantom", chainId: 250, rpcUrl: "https://rpc.ankr.com/fantom", symbol: "FTM", explorerUrl: "https://ftmscan.com" }, sepolia: { name: "Sepolia Testnet", chainId: 11155111, rpcUrl: "https://rpc.ankr.com/eth_sepolia", symbol: "ETH", explorerUrl: "https://sepolia.etherscan.io" } }; export class RpcService { private providers: Map<string, ethers.JsonRpcProvider> = new Map(); constructor() { // Initialize providers for all default chains for (const [key, config] of Object.entries(DEFAULT_CHAINS)) { this.providers.set(key, new ethers.JsonRpcProvider(config.rpcUrl)); } } registerWithServer(server: McpServer) { server.registerTool( "static-call", { title: "Static Call", description: "Make a static call to a smart contract on any EVM-compatible chain (read-only)", inputSchema: { chain: z.string().describe(`Chain identifier. Available: ${Object.keys(DEFAULT_CHAINS).join(', ')}`), to: z.string().describe("Contract address to call"), data: z.string().describe("ABI-encoded function call data"), blockTag: z.string().optional().describe("Block tag (latest, earliest, pending, or block number)").default("latest") } }, async ({ chain, to, data, blockTag = "latest" }) => { try { const chainConfig = DEFAULT_CHAINS[chain.toLowerCase()]; if (!chainConfig) { return { content: [{ type: "text", text: `Error: Unsupported chain "${chain}". Available chains: ${Object.keys(DEFAULT_CHAINS).join(', ')}` }], isError: true }; } if (!ethers.isAddress(to)) { return { content: [{ type: "text", text: `Error: Invalid contract address: ${to}` }], isError: true }; } const provider = this.providers.get(chain.toLowerCase()); if (!provider) { return { content: [{ type: "text", text: `Error: Provider not initialized for chain: ${chain}` }], isError: true }; } const result = await provider.call({ to: to, data: data }); return { content: [{ type: "text", text: `Static call result: 🔗 Chain: ${chainConfig.name} (${chainConfig.chainId}) 📄 Contract: ${to} 📊 Call Data: ${data} 🏷️ Block: ${blockTag} 📤 Result: ${result} ${chainConfig.explorerUrl ? `🔍 Explorer: ${chainConfig.explorerUrl}/address/${to}` : ''}` }] }; } catch (error) { return { content: [{ type: "text", text: `Error making static call: ${error instanceof Error ? error.message : String(error)}` }], isError: true }; } } ); server.registerTool( "send-transaction", { title: "Send Transaction", description: "Send a transaction to a smart contract on any EVM-compatible chain (requires private key)", inputSchema: { chain: z.string().describe(`Chain identifier. Available: ${Object.keys(DEFAULT_CHAINS).join(', ')}`), to: z.string().describe("Contract address to call"), data: z.string().describe("ABI-encoded function call data"), value: z.string().optional().describe("ETH value to send (in wei)").default("0"), gasLimit: z.string().optional().describe("Gas limit for the transaction"), gasPrice: z.string().optional().describe("Gas price (in wei)"), privateKey: z.string().describe("Private key of the sender (will be handled securely)") } }, async ({ chain, to, data, value = "0", gasLimit, gasPrice, privateKey }) => { try { const chainConfig = DEFAULT_CHAINS[chain.toLowerCase()]; if (!chainConfig) { return { content: [{ type: "text", text: `Error: Unsupported chain "${chain}". Available chains: ${Object.keys(DEFAULT_CHAINS).join(', ')}` }], isError: true }; } if (!ethers.isAddress(to)) { return { content: [{ type: "text", text: `Error: Invalid contract address: ${to}` }], isError: true }; } // Validate private key let wallet: ethers.Wallet; try { wallet = new ethers.Wallet(privateKey); } catch { return { content: [{ type: "text", text: "Error: Invalid private key format" }], isError: true }; } const provider = this.providers.get(chain.toLowerCase()); if (!provider) { return { content: [{ type: "text", text: `Error: Provider not initialized for chain: ${chain}` }], isError: true }; } const connectedWallet = wallet.connect(provider); // Prepare transaction const tx: any = { to: to, data: data, value: value }; if (gasLimit) { tx.gasLimit = gasLimit; } if (gasPrice) { tx.gasPrice = gasPrice; } // Get current nonce and balance const [nonce, balance] = await Promise.all([ connectedWallet.getNonce(), provider.getBalance(wallet.address) ]); // Estimate gas if not provided if (!gasLimit) { try { const estimatedGas = await connectedWallet.estimateGas(tx); tx.gasLimit = estimatedGas; } catch (error) { return { content: [{ type: "text", text: `Error estimating gas: ${error instanceof Error ? error.message : String(error)}` }], isError: true }; } } // Send transaction const txResponse = await connectedWallet.sendTransaction(tx); return { content: [{ type: "text", text: `Transaction sent successfully! 🔗 Chain: ${chainConfig.name} (${chainConfig.chainId}) 📄 Contract: ${to} 👤 From: ${wallet.address} 💰 Value: ${ethers.formatEther(value)} ${chainConfig.symbol} ⛽ Gas Limit: ${tx.gasLimit?.toString()} 🔢 Nonce: ${nonce} 📝 Transaction Hash: ${txResponse.hash} 🔍 Explorer: ${chainConfig.explorerUrl}/tx/${txResponse.hash} ⏳ Transaction is pending confirmation... 💰 Account Balance: ${ethers.formatEther(balance)} ${chainConfig.symbol}` }] }; } catch (error) { return { content: [{ type: "text", text: `Error sending transaction: ${error instanceof Error ? error.message : String(error)}` }], isError: true }; } } ); server.registerTool( "get-balance", { title: "Get Balance", description: "Get the balance of an address on any EVM-compatible chain", inputSchema: { chain: z.string().describe(`Chain identifier. Available: ${Object.keys(DEFAULT_CHAINS).join(', ')}`), address: z.string().describe("Address to check balance for"), blockTag: z.string().optional().describe("Block tag (latest, earliest, pending, or block number)").default("latest") } }, async ({ chain, address, blockTag = "latest" }) => { try { const chainConfig = DEFAULT_CHAINS[chain.toLowerCase()]; if (!chainConfig) { return { content: [{ type: "text", text: `Error: Unsupported chain "${chain}". Available chains: ${Object.keys(DEFAULT_CHAINS).join(', ')}` }], isError: true }; } if (!ethers.isAddress(address)) { return { content: [{ type: "text", text: `Error: Invalid address: ${address}` }], isError: true }; } const provider = this.providers.get(chain.toLowerCase()); if (!provider) { return { content: [{ type: "text", text: `Error: Provider not initialized for chain: ${chain}` }], isError: true }; } const balance = await provider.getBalance(address, blockTag); return { content: [{ type: "text", text: `Balance Information: 🔗 Chain: ${chainConfig.name} (${chainConfig.chainId}) 👤 Address: ${address} 🏷️ Block: ${blockTag} 💰 Balance: ${ethers.formatEther(balance)} ${chainConfig.symbol} 🔢 Wei: ${balance.toString()} ${chainConfig.explorerUrl ? `🔍 Explorer: ${chainConfig.explorerUrl}/address/${address}` : ''}` }] }; } catch (error) { return { content: [{ type: "text", text: `Error getting balance: ${error instanceof Error ? error.message : String(error)}` }], isError: true }; } } ); server.registerTool( "list-chains", { title: "List Supported Chains", description: "List all supported EVM-compatible chains and their configurations", inputSchema: {} }, async () => { const chainsList = Object.entries(DEFAULT_CHAINS).map(([key, config]) => `🔗 ${key}: ${config.name} (Chain ID: ${config.chainId}) RPC: ${config.rpcUrl} Symbol: ${config.symbol} ${config.explorerUrl ? `Explorer: ${config.explorerUrl}` : ''}` ).join('\n\n'); return { content: [{ type: "text", text: `Supported EVM-Compatible Chains: ${chainsList} Usage: Use the chain key (e.g., "ethereum", "polygon", "bsc") in other RPC tools.` }] }; } ); } }