MCP Sandbox

import * as vm from 'vm'; import { MCPTool, ExecutionResult } from './types'; export class ToolExecutor { private timeout: number; private context: vm.Context; private tools: Map<string, MCPTool>; constructor(context: vm.Context, timeout: number = 5000) { this.context = context; this.timeout = timeout; this.tools = new Map(); } addTool(tool: MCPTool): void { this.tools.set(tool.name, tool); } addTools(tools: MCPTool[]): void { tools.forEach((tool) => this.addTool(tool)); } getTools(): MCPTool[] { return Array.from(this.tools.values()); } getTool(name: string): MCPTool | undefined { return this.tools.get(name); } /** * Execute a tool in the sandbox */ async executeTool(toolName: string, args: Record<string, any> = {}): Promise<ExecutionResult> { const tool = this.tools.get(toolName); if (!tool) { throw new Error(`Tool '${toolName}' not found`); } const startTime = Date.now(); try { // Create execution context with memory limits const executionContext = { ...this.context, args, result: null, error: null, }; const result = await new Promise((resolve, reject) => { const timeout = setTimeout(() => { reject(new Error('Execution timeout')); }, this.timeout); try { const output = tool.handler.apply(executionContext, Object.values(args)); clearTimeout(timeout); if (output instanceof Promise) { output.then(resolve).catch(reject); } else { resolve(output); } } catch (error) { clearTimeout(timeout); reject(error); } }); return { success: true, result, toolName, executionTime: Date.now() - startTime, }; } catch (error) { return { success: false, error: error instanceof Error ? error.message : String(error), toolName, executionTime: Date.now() - startTime, }; } } }