MCP Tools

import _ from 'lodash' import { z } from 'zod' import env from '../env.js' import { defineTool } from '../tools.js' import util from '../util.js' const importSymbol = defineTool({ id: 'import_symbol', schema: z.object({ module_path: z.string().min(1).describe('Module path to import (e.g., "lodash", "./utils", "@package/name")'), property: z.string().optional().describe('Only the given property from the module is dumped'), }), description: 'Import and inspect JavaScript/TypeScript modules ala require(), or import()', isReadOnly: true, isEnabled: env.DEBUG, fromArgs: ([module_path, property]) => ({ module_path, property: property || undefined }), handler: async (args) => { const { module_path: modulePath, property } = args const resolvedPath = modulePath.startsWith('.') ? util.resolve(modulePath) : modulePath let module = await import(resolvedPath) if (module.default) { module = module.default } const target = property ? _.get(module, property) : module if (target === undefined) { throw new Error(`Property '${property}' not found in module '${modulePath}'`) } const output: string[] = [] output.push(`=== ${modulePath}${property ? `.${property}` : ''} ===`) output.push(dumpValue(target)) return output.join('\n') }, }) export default importSymbol const MAX_VALUE_LENGTH = 300 function dumpValue(value: any): string { const type = typeof value const output: string[] = [] if (type === 'object' && value !== null) { const keys = Object.keys(value).sort() if (keys.length > 0) { if (_.isArray(value)) { const elementType = typeof value[0] output.push(`${elementType}[${value.length}]`) } else if (_.isPlainObject(value)) { output.push('object') } else { output.push(`object (${value.constructor.name})`) } keys.forEach((key) => { if (!key.startsWith('_')) { output.push(`${key}: ${dump(value[key])}`) } }) return output.join('\n') } } return dump(value) } function dump(value: any): string { const type = typeof value if (type === 'function') { if (isClass(value)) { return `class ${getClassSignature(value)}` } return `function ${getFunctionSignature(value)}` } if (_.isArray(value)) { const json = JSON.stringify(value) if (json.length <= MAX_VALUE_LENGTH) { return json } const type = typeof value[0] return `${type}[${value.length}]` } if (_.isPlainObject(value)) { const json = JSON.stringify(value) if (json.length <= MAX_VALUE_LENGTH) { return json } const keys = Object.keys(value) return `object (${keys.length} properties)` } if (type === 'object' && value !== null) { return value.constructor.name } return JSON.stringify(value) } function isClass(func: Function): boolean { return func.toString().startsWith('class ') } function getFunctionSignature(func: Function): string { try { const str = func.toString() const match = str.match(/\(([^)]*)\)/) if (match?.[1]) { const params = match[1].split(',').map(p => p.trim().split('=')[0]?.trim()).filter(Boolean) return `(${params.join(', ')})` } return '(...)' } catch { return '(...)' } } function getClassSignature(cls: Function): string { try { const match = cls.toString().match(/constructor\s*\(([^)]*)\)/) if (match?.[1]) { const params = match[1].split(',').map(p => p.trim().split('=')?.[0]?.trim()).filter(p => p) return `(${params.join(', ')})` } return getFunctionSignature(cls) } catch { return '(...)' } }