@jwalsh/mcp-server-qrcode
Version:
Model Context Protocol server for generating QR codes
700 lines (699 loc) • 27.8 kB
JavaScript
import { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js';
import { z } from 'zod';
import { generateQRCode } from './qrcode.js';
// Create an MCP server
const server = new McpServer({
name: 'QR Code Generator',
version: '0.3.6',
});
// Register capabilities
server.server.registerCapabilities({
resources: {
root: 'qrcode://',
get: true,
list: true,
},
prompts: {
list: true,
},
});
// Add the QR code generation tool
server.tool('generate-qrcode', 'Generate QR codes in various formats with customizable error correction levels and sizes', {
content: z.string().describe('The text content to encode in the QR code'),
errorCorrectionLevel: z
.enum(['L', 'M', 'Q', 'H'])
.describe('Error correction level (L: 7%, M: 15%, Q: 25%, H: 30%)')
.optional()
.default('M'),
size: z.number().min(1).max(10).describe('Size of the QR code (1-10)').optional().default(3),
format: z
.enum(['image', 'text'])
.describe("Output format: 'image' for PNG QR code, 'text' for terminal-friendly output")
.optional()
.default('image'),
}, async (args, _extra) => {
try {
const { content, errorCorrectionLevel, size, format } = args;
// Convert size from 1-10 scale to pixel size
const pixelSize = size * 100;
if (format === 'text') {
// Generate QR code in UTF8/terminal format
const result = await generateQRCode({
content,
size: pixelSize,
errorCorrectionLevel,
format: 'terminal',
});
return {
content: [
{
type: 'text',
text: `QR code generated for: ${content}`,
},
{
type: 'text',
text: result.data,
},
],
};
}
else {
// Generate QR code as PNG and return as base64
const result = await generateQRCode({
content,
size: pixelSize,
errorCorrectionLevel,
format: 'base64',
});
// Ensure we're sending clean base64 data
// Remove any data URL prefixes if present
const imageData = result.data.startsWith('data:') ? result.data.split(',')[1] : result.data;
return {
content: [
{
type: 'text',
text: `QR code generated for: ${content}`,
},
{
type: 'image',
data: imageData,
mimeType: 'image/png',
},
],
};
}
}
catch (error) {
const errorMessage = error instanceof Error ? error.message : String(error);
return {
content: [{ type: 'text', text: `Failed to generate QR code: ${errorMessage}` }],
isError: true,
};
}
});
// Set up resource handlers manually to work with the MCP protocol
const resourcesListRequestSchema = z.object({
method: z.literal('resources/list'),
params: z.object({}),
});
server.server.setRequestHandler(resourcesListRequestSchema, async () => {
// Return a list of available QR code resources
return {
resources: [
{
uri: 'qrcode://sample',
name: 'Sample QR Code',
description: 'A sample QR code that links to the project repository',
},
{
uri: 'qrcode://hello-world',
name: 'Hello World',
description: 'A simple Hello World QR code example',
},
{
uri: 'qrcode://wifi?ssid=MyNetwork&password=password123&encryption=WPA',
name: 'WiFi QR Code',
description: 'Generate a QR code to connect to WiFi',
},
{
uri: 'qrcode://contact?name=John%20Doe&phone=555-123-4567&email=john@example.com',
name: 'Contact QR Code',
description: 'Generate a QR code with contact information',
},
{
uri: 'qrcode://url?url=https://anthropic.com',
name: 'URL QR Code',
description: 'Generate a QR code for a URL',
},
{
uri: 'qrcode://text?content=Hello%20World!&size=250&level=Q',
name: 'Text QR Code',
description: 'Generate a QR code containing plain text',
},
{
uri: 'qrcode://calendar?title=Team%20Meeting&start=2025-03-15T10:00:00&end=2025-03-15T11:00:00',
name: 'Calendar Event QR Code',
description: 'Generate a QR code for a calendar event',
},
],
};
});
// Add resource retrieval method
const resourcesGetRequestSchema = z.object({
method: z.literal('resources/get'),
params: z.object({
uri: z.string().describe('The resource URI to retrieve'),
}),
});
server.server.setRequestHandler(resourcesGetRequestSchema, async (request) => {
const uri = request.params.uri;
try {
// Validate URI format
if (!uri.startsWith('qrcode://')) {
throw new Error('Resource URI must start with qrcode://');
}
// Determine resource type and parameters
let content = '';
let size = 300;
let errorCorrectionLevel = 'M';
if (uri === 'qrcode://sample') {
// Sample QR code
const result = await generateQRCode({
content: 'https://github.com/jwalsh/mcp-server-qrcode',
size,
errorCorrectionLevel,
format: 'base64',
});
return {
contents: [
{
text: 'Sample QR Code for MCP QR Code Server',
uri: 'qrcode://sample',
},
{
uri: 'qrcode://sample',
blob: result.data,
mimeType: 'image/png',
},
],
};
}
else if (uri === 'qrcode://hello-world') {
// Hello World QR code
const result = await generateQRCode({
content: 'Hello, World!',
size,
errorCorrectionLevel,
format: 'base64',
});
return {
contents: [
{
text: 'Hello World QR Code Example',
uri: 'qrcode://hello-world',
},
{
uri: 'qrcode://hello-world',
blob: result.data,
mimeType: 'image/png',
},
],
};
}
else if (uri.startsWith('qrcode://wifi?')) {
// WiFi template
const queryString = uri.split('?')[1] || '';
const queryParams = new URLSearchParams(queryString);
const ssid = queryParams.get('ssid');
if (!ssid) {
throw new Error('SSID is required for WiFi QR code');
}
const password = queryParams.get('password') || '';
const encryption = queryParams.get('encryption')?.toUpperCase() || 'WPA';
// Generate WiFi connection string in standard format
// Format: WIFI:T:<encryption>;S:<ssid>;P:<password>;;
const wifiContent = `WIFI:T:${encryption};S:${ssid};P:${password};;`;
const result = await generateQRCode({
content: wifiContent,
size,
errorCorrectionLevel,
format: 'base64',
});
return {
contents: [
{
text: `WiFi QR Code for "${ssid}"`,
uri: uri,
},
{
uri: uri,
blob: result.data,
mimeType: 'image/png',
},
],
};
}
else if (uri.startsWith('qrcode://contact?')) {
// Contact template
const queryString = uri.split('?')[1] || '';
const queryParams = new URLSearchParams(queryString);
const name = queryParams.get('name');
if (!name) {
throw new Error('Name is required for contact QR code');
}
const phone = queryParams.get('phone') || '';
const email = queryParams.get('email') || '';
const organization = queryParams.get('organization') || '';
const title = queryParams.get('title') || '';
const url = queryParams.get('url') || '';
const address = queryParams.get('address') || '';
// Generate contact string in vCard format
const vcard = [
'BEGIN:VCARD',
'VERSION:3.0',
`FN:${name}`,
phone ? `TEL:${phone}` : '',
email ? `EMAIL:${email}` : '',
organization ? `ORG:${organization}` : '',
title ? `TITLE:${title}` : '',
url ? `URL:${url}` : '',
address ? `ADR:;;${address};;;` : '',
'END:VCARD',
]
.filter(line => line)
.join('\n');
const result = await generateQRCode({
content: vcard,
size,
errorCorrectionLevel,
format: 'base64',
});
return {
contents: [
{
text: `Contact QR Code for "${name}"`,
uri: uri,
},
{
uri: uri,
blob: result.data,
mimeType: 'image/png',
},
],
};
}
else if (uri.startsWith('qrcode://url?')) {
// URL template
const queryString = uri.split('?')[1] || '';
const queryParams = new URLSearchParams(queryString);
const url = queryParams.get('url');
if (!url) {
throw new Error('URL is required for URL QR code');
}
// Parse size parameter if present
if (queryParams.has('size')) {
const sizeParam = parseInt(queryParams.get('size'), 10);
if (!isNaN(sizeParam)) {
size = sizeParam;
}
}
// Parse error correction level if present
const levelParam = queryParams.get('level');
if (levelParam && ['L', 'M', 'Q', 'H'].includes(levelParam)) {
errorCorrectionLevel = levelParam;
}
const result = await generateQRCode({
content: url,
size,
errorCorrectionLevel,
format: 'base64',
});
return {
contents: [
{
text: `URL QR Code for "${url}"`,
uri: uri,
},
{
uri: uri,
blob: result.data,
mimeType: 'image/png',
},
],
};
}
else if (uri.startsWith('qrcode://text?')) {
// Text template
const queryString = uri.split('?')[1] || '';
const queryParams = new URLSearchParams(queryString);
const content = queryParams.get('content');
if (!content) {
throw new Error('Content is required for text QR code');
}
// Parse size parameter if present
if (queryParams.has('size')) {
const sizeParam = parseInt(queryParams.get('size'), 10);
if (!isNaN(sizeParam)) {
size = sizeParam;
}
}
// Parse error correction level if present
const levelParam = queryParams.get('level');
if (levelParam && ['L', 'M', 'Q', 'H'].includes(levelParam)) {
errorCorrectionLevel = levelParam;
}
const result = await generateQRCode({
content: decodeURIComponent(content),
size,
errorCorrectionLevel,
format: 'base64',
});
return {
contents: [
{
text: `Text QR Code: "${decodeURIComponent(content)}"`,
uri: uri,
},
{
uri: uri,
blob: result.data,
mimeType: 'image/png',
},
],
};
}
else if (uri.startsWith('qrcode://calendar?')) {
// Calendar template
const queryString = uri.split('?')[1] || '';
const queryParams = new URLSearchParams(queryString);
const title = queryParams.get('title');
if (!title) {
throw new Error('Title is required for calendar event QR code');
}
const start = queryParams.get('start');
if (!start) {
throw new Error('Start time is required for calendar event QR code');
}
const end = queryParams.get('end') || '';
const location = queryParams.get('location') || '';
const description = queryParams.get('description') || '';
// Generate calendar string in iCalendar format
const uid = `event-${Date.now()}@qrcode-generator`;
const now = new Date().toISOString().replace(/[-:.]/g, '').slice(0, 15) + 'Z';
const ical = [
'BEGIN:VCALENDAR',
'VERSION:2.0',
'PRODID:-//MCP QR Code Generator//EN',
'BEGIN:VEVENT',
`UID:${uid}`,
`DTSTAMP:${now}`,
`DTSTART:${start.replace(/[-:.]/g, '').slice(0, 15)}Z`,
end ? `DTEND:${end.replace(/[-:.]/g, '').slice(0, 15)}Z` : '',
`SUMMARY:${title}`,
location ? `LOCATION:${location}` : '',
description ? `DESCRIPTION:${description}` : '',
'END:VEVENT',
'END:VCALENDAR',
]
.filter(line => line)
.join('\r\n');
// Parse size and error correction parameters
if (queryParams.has('size')) {
const sizeParam = parseInt(queryParams.get('size'), 10);
if (!isNaN(sizeParam)) {
size = sizeParam;
}
}
const levelParam = queryParams.get('level');
if (levelParam && ['L', 'M', 'Q', 'H'].includes(levelParam)) {
errorCorrectionLevel = levelParam;
}
const result = await generateQRCode({
content: ical,
size,
errorCorrectionLevel,
format: 'base64',
});
return {
contents: [
{
text: `Calendar Event QR Code: "${title}"`,
uri: uri,
},
{
uri: uri,
blob: result.data,
mimeType: 'image/png',
},
],
};
}
else {
// Custom resource - Extract content and parameters from the URI
const contentMatch = uri.match(/^qrcode:\/\/(.+?)(?:\?|$)/);
content = contentMatch ? contentMatch[1] : '';
if (!content) {
throw new Error('Content parameter is required');
}
// Extract query parameters
const queryString = uri.includes('?') ? uri.split('?')[1] : '';
const queryParams = new URLSearchParams(queryString);
// Parse size parameter if present
if (queryParams.has('size')) {
const sizeParam = parseInt(queryParams.get('size'), 10);
if (!isNaN(sizeParam)) {
size = sizeParam;
}
}
// Parse error correction level if present
const levelParam = queryParams.get('level');
if (levelParam && ['L', 'M', 'Q', 'H'].includes(levelParam)) {
errorCorrectionLevel = levelParam;
}
// Generate QR code
const result = await generateQRCode({
content: decodeURIComponent(content),
size,
errorCorrectionLevel,
format: 'base64',
});
return {
contents: [
{
text: `QR Code for "${decodeURIComponent(content)}"`,
uri: uri,
},
{
uri: uri,
blob: result.data,
mimeType: 'image/png',
},
],
};
}
}
catch (error) {
const errorMessage = error instanceof Error ? error.message : String(error);
return {
contents: [{ text: `Failed to retrieve resource: ${errorMessage}`, uri: uri }],
isError: true,
};
}
});
// Add resource templates list method
const resourcesTemplatesListRequestSchema = z.object({
method: z.literal('resources/templates/list'),
params: z.object({}),
});
server.server.setRequestHandler(resourcesTemplatesListRequestSchema, async () => {
// Return a list of available QR code resource templates
return {
resourceTemplates: [
{
name: 'wifi-template',
description: 'Generate a QR code that connects devices to a WiFi network',
example: 'qrcode://wifi?ssid=MyWiFiNetwork&password=securepassword&encryption=WPA',
inputSchema: {
type: 'object',
properties: {
ssid: {
type: 'string',
description: 'Network name',
},
encryption: {
type: 'string',
enum: ['WPA', 'WEP', 'nopass'],
description: 'Encryption type',
},
password: {
type: 'string',
description: 'Network password',
},
hidden: {
type: 'boolean',
description: 'Whether the network is hidden',
default: false,
},
},
required: ['ssid', 'encryption'],
},
},
{
name: 'contact-template',
description: 'Generate a QR code containing contact information in vCard format',
example: 'qrcode://contact?name=Jane%20Doe&phone=555-123-4567&email=jane@example.com',
inputSchema: {
type: 'object',
properties: {
name: {
type: 'string',
description: 'Contact name',
},
phone: {
type: 'string',
description: 'Phone number',
},
email: {
type: 'string',
description: 'Email address',
},
organization: {
type: 'string',
description: 'Organization or company name',
},
title: {
type: 'string',
description: 'Job title or position',
},
url: {
type: 'string',
description: 'Website URL',
},
address: {
type: 'string',
description: 'Physical address',
},
},
required: ['name'],
},
},
{
name: 'url-template',
description: 'Generate a QR code that opens a website or web resource',
example: 'qrcode://url?url=https://example.com&size=300&level=H',
inputSchema: {
type: 'object',
properties: {
url: {
type: 'string',
description: 'URL to encode',
},
size: {
type: 'number',
description: 'Size of the QR code (100-1000 pixels)',
default: 300,
},
level: {
type: 'string',
enum: ['L', 'M', 'Q', 'H'],
description: 'Error correction level',
default: 'M',
},
},
required: ['url'],
},
},
{
name: 'text-template',
description: 'Generate a QR code containing plain text',
example: 'qrcode://text?content=This%20is%20a%20sample%20text%20message&size=250&level=Q',
inputSchema: {
type: 'object',
properties: {
content: {
type: 'string',
description: 'Text content to encode',
},
size: {
type: 'number',
description: 'Size of the QR code (100-1000 pixels)',
default: 250,
},
level: {
type: 'string',
enum: ['L', 'M', 'Q', 'H'],
description: 'Error correction level',
default: 'M',
},
},
required: ['content'],
},
},
{
name: 'calendar-template',
description: 'Generate a QR code for calendar events in iCalendar format',
example: 'qrcode://calendar?title=Team%20Meeting&start=2025-03-15T10:00:00&end=2025-03-15T11:00:00&location=Conference%20Room&description=Weekly%20team%20sync',
inputSchema: {
type: 'object',
properties: {
title: {
type: 'string',
description: 'Event title',
},
start: {
type: 'string',
description: 'Start time in ISO format (YYYY-MM-DDTHH:MM:SS)',
},
end: {
type: 'string',
description: 'End time in ISO format (YYYY-MM-DDTHH:MM:SS)',
},
location: {
type: 'string',
description: 'Event location',
},
description: {
type: 'string',
description: 'Event description',
},
},
required: ['title', 'start'],
},
},
],
};
});
// Add prompts list method
const promptsListRequestSchema = z.object({
method: z.literal('prompts/list'),
params: z.object({}),
});
server.server.setRequestHandler(promptsListRequestSchema, async () => {
// Return a list of example prompts for QR code generation
return {
prompts: [
{
name: 'create-wifi-qr',
description: 'Create a QR code for connecting to a WiFi network',
prompt: "Generate a QR code that allows people to connect to my home WiFi network called 'MyHomeNetwork' with password 'secure123' using WPA encryption",
},
{
name: 'create-contact-qr',
description: 'Create a QR code with contact information',
prompt: 'Create a QR code with my contact information: name: Jane Smith, phone: 555-987-6543, email: jane@example.com, organization: ABC Corp, title: Senior Developer',
},
{
name: 'create-url-qr',
description: 'Create a QR code for a website URL',
prompt: 'Make a QR code for my website at https://example.com with high error correction',
},
{
name: 'create-text-qr',
description: 'Create a QR code with plain text',
prompt: "Generate a QR code with this text message: 'Thank you for visiting our booth at the conference! Use discount code CONF2025 for 20% off your next purchase.'",
},
{
name: 'create-calendar-qr',
description: 'Create a QR code for a calendar event',
prompt: "Create a QR code for our team meeting on March 15, 2025 from 10:00 AM to 11:30 AM in Conference Room A with the description 'Quarterly planning session'",
},
{
name: 'create-custom-sized-qr',
description: 'Create a QR code with custom size settings',
prompt: 'Generate a large QR code (size 8) for my business URL https://mybusiness.example.com',
},
{
name: 'qr-with-high-error-correction',
description: 'Create a QR code with high error correction level',
prompt: 'Create a QR code for https://example.org with the highest possible error correction level for maximum reliability',
},
{
name: 'text-output-qr',
description: 'Create a QR code with text output format',
prompt: "Generate a QR code for 'Hello World' and display it as ASCII/text art that I can paste into a document",
},
],
};
});
// Export the server instance to be used with a transport
export default server;