Foundry MCP Server

import { z } from "zod"; import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js"; import { checkFoundryInstalled, executeCommand, FOUNDRY_PATHS, FOUNDRY_NOT_INSTALLED_ERROR } from "../../utils/command.js"; import { resolveRpcUrl } from "../../utils/rpc.js"; export function registerCastBalanceTool(server: McpServer): void { server.tool( "cast_balance", "Check the ETH balance of an address", { address: z.string().describe("Ethereum address to check balance for"), rpcUrl: z.string().optional().describe("JSON-RPC URL (default: http://localhost:8545)"), blockNumber: z.string().optional().describe("Block number (e.g., 'latest', 'earliest', or a number)"), formatEther: z.boolean().optional().describe("Format the balance in Ether (default: wei)") }, async ({ address, rpcUrl, blockNumber, formatEther = false }) => { const installed = await checkFoundryInstalled(); if (!installed) { return { content: [{ type: "text", text: FOUNDRY_NOT_INSTALLED_ERROR }], isError: true }; } const resolvedRpcUrl = await resolveRpcUrl(rpcUrl); let command = `${FOUNDRY_PATHS.castPath} balance ${address}`; if (resolvedRpcUrl) { command += ` --rpc-url "${resolvedRpcUrl}"`; } if (blockNumber) { command += ` --block ${blockNumber}`; } if (formatEther) { command += " --ether"; } const result = await executeCommand(command); const unit = formatEther ? "ETH" : "wei"; return { content: [{ type: "text", text: result.success ? `Balance of ${address}: ${result.message.trim()} ${unit}` : `Failed to get balance: ${result.message}` }], isError: !result.success }; } ); }