ExpressJS MCP

import type { Application } from "express"; import type { ExpressMCPOptions, RouteInfo } from "./index"; export class RouteIntrospector { constructor(private app: Application) {} listRoutes(options?: ExpressMCPOptions): RouteInfo[] { const router: unknown = (this.app as unknown)._router; if (!router || !("stack" in router)) { return []; } const routes: RouteInfo[] = []; const push = (path: string, route: unknown) => { if ( !route || typeof route !== "object" || !("stack" in route) || !("methods" in route) ) { return; } const stack = (route as { stack?: unknown[] }).stack || []; const handlers = stack .map((s: unknown) => s && typeof s === "object" && "handle" in s ? (s as { handle: unknown }).handle : null, ) .filter(Boolean); const handler = handlers[handlers.length - 1] as ( ...args: unknown[] ) => unknown; const middlewares = handlers.slice(0, -1) as (( ...args: unknown[] ) => unknown)[]; const methods = (route as { methods: Record<string, boolean> }).methods; for (const method of Object.keys(methods)) { const info = { method: method.toUpperCase(), path, middlewares, handler, }; if (options?.include && !options.include(info)) continue; if (options?.exclude?.(info)) continue; routes.push(info); } }; for (const layer of (router as { stack: unknown[] }).stack) { const layerObj = layer as { route?: unknown; name?: string; handle?: { stack?: unknown[] }; }; // Check if this layer has a route directly if (layerObj.route) { const route = layerObj.route as { path: string }; push(route.path, layerObj.route); } // Check if this is a nested router else if (layerObj.name === "router" && layerObj.handle?.stack) { for (const sub of layerObj.handle.stack) { const subObj = sub as { route?: unknown }; if (subObj.route) { const subRoute = subObj.route as { path: string }; push(subRoute.path, subObj.route); } } } } return routes; } }