URL2QR MCP Server

import QRCode from "qrcode"; import { randomUUID } from "node:crypto"; import { promises as fs } from "node:fs"; import path from "node:path"; export const url2qr = { name: "url_to_qrcode", description: "Convert a URL into a QR code image and return the download link. The QR code will be saved as a PNG file and accessible via HTTP.", parameters: { type: "object", properties: { url: { type: "string", description: "The URL to convert into a QR code (e.g., https://example.com)" }, errorCorrectionLevel: { type: "string", enum: ["L", "M", "Q", "H"], description: "QR code error correction level. L=Low(7%), M=Medium(15%), Q=Quartile(25%), H=High(30%). Default: M" }, width: { type: "number", description: "Width of the QR code image in pixels. Default: 300" } }, required: ["url"] }, async run( args: { url: string; errorCorrectionLevel?: "L" | "M" | "Q" | "H"; width?: number }, context?: { hostBaseUrl?: string } ) { try { // 1️⃣ Parameter validation if (!args.url) { throw new Error("URL parameter is required"); } // Validate URL format try { new URL(args.url); } catch (e) { throw new Error(`Invalid URL format: ${args.url}`); } // 2️⃣ Set default values const errorCorrectionLevel = args.errorCorrectionLevel || "M"; const width = args.width || 300; // 3️⃣ Generate QR code const qrOutputDir = process.env.QR_OUTPUT_DIR || "./qrcodes"; // Ensure output directory exists await fs.mkdir(qrOutputDir, { recursive: true }); // Generate unique filename const filename = `qr-${randomUUID()}.png`; const filePath = path.join(qrOutputDir, filename); // Generate QR code with options await QRCode.toFile(filePath, args.url, { errorCorrectionLevel, width, type: "png", color: { dark: "#000000", light: "#FFFFFF" } }); // 4️⃣ Build download URL - Auto-detect from request or use environment variable // Priority: 1) Request host (dynamic) 2) Environment variable 3) Localhost fallback const port = process.env.PORT || 3000; let downloadBaseUrl: string; if (context?.hostBaseUrl) { // Use dynamically detected host from request downloadBaseUrl = context.hostBaseUrl.replace(/\/$/, ""); } else if (process.env.PUBLIC_BASE_URL) { // Use configured public URL downloadBaseUrl = process.env.PUBLIC_BASE_URL.replace(/\/$/, ""); } else { // Fallback to localhost downloadBaseUrl = `http://localhost:${port}`; } const downloadUrl = `${downloadBaseUrl}/qrcodes/${filename}`; // 5️⃣ Format return return { content: [{ type: "text" as const, text: `# ✅ QR Code Generated Successfully **Original URL:** ${args.url} **Download Link:** ${downloadUrl} **QR Code Details:** - Filename: ${filename} - Size: ${width}x${width}px - Error Correction: ${errorCorrectionLevel} You can download the QR code image from the link above.` }] }; } catch (error: any) { return { content: [{ type: "text" as const, text: `❌ Failed to generate QR code: ${error.message}` }], isError: true }; } } };