import { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js';
import { SSEServerTransport } from '@modelcontextprotocol/sdk/server/sse.js';
import type { VercelRequest, VercelResponse } from '@vercel/node';
import { HardcoverClient } from '../lib/hardcover-client.js';
const HARDCOVERAPI_KEY = process.env.HARDCOVERAPI_KEY || '';
export default async function handler(req: VercelRequest, res: VercelResponse) {
console.log('MCP API handler called', { method: req.method, url: req.url });
// Set CORS headers
res.setHeader('Access-Control-Allow-Origin', '*');
res.setHeader('Access-Control-Allow-Methods', 'GET, POST, OPTIONS');
res.setHeader('Access-Control-Allow-Headers', 'Content-Type');
// Handle OPTIONS request
if (req.method === 'OPTIONS') {
console.log('Handling OPTIONS request');
res.status(200).end();
return;
}
if (req.method === 'GET' || req.method === 'POST') {
try {
console.log('Setting up MCP server');
// For debugging, let's first try a super simple response to test connection
if (req.query.test === 'true') {
console.log('Test mode - sending simple response');
res.status(200).json({ status: 'ok', message: 'MCP server running' });
return;
}
console.log('Creating SSE transport');
const transport = new SSEServerTransport('/api/mcp', res);
console.log('Creating MCP server');
const server = new McpServer({
name: 'Hardcover MCP',
version: '1.0.0'
});
console.log('Creating Hardcover client');
const client = new HardcoverClient(HARDCOVERAPI_KEY);
console.log('API Key length:', HARDCOVERAPI_KEY ? HARDCOVERAPI_KEY.length : 0);
console.log('Registering search_books tool');
server.registerTool(
'search_books',
{
title: 'Search Books',
description: 'Search for books by title, author, or ISBN'
},
{
parameters: {
type: 'object',
properties: {
query: {
type: 'string',
description: 'Search query (title, author, or ISBN)',
},
limit: {
type: 'number',
description: 'Maximum number of results to return',
default: 10,
},
},
required: ['query'],
},
execute: async ({ query, limit = 10 }: { query: string; limit?: number }) => {
console.log('Executing search_books', { query, limit });
try {
const books = await client.searchBooks(query, limit);
console.log('Search results', { count: books.length });
return books;
} catch (error) {
console.error('Error searching books:', error);
return { error: `Failed to search books: ${error instanceof Error ? error.message : String(error)}` };
}
}
}
);
console.log('Registering get_book_details tool');
server.registerTool(
'get_book_details',
{
title: 'Get Book Details',
description: 'Get detailed information about a specific book by ID'
},
{
parameters: {
type: 'object',
properties: {
book_id: {
type: 'number',
description: 'Hardcover book ID',
},
},
required: ['book_id'],
},
execute: async ({ book_id }: { book_id: number }) => {
console.log('Executing get_book_details', { book_id });
try {
const book = await client.getBookDetails(book_id);
console.log('Book details retrieved');
return book;
} catch (error) {
console.error('Error getting book details:', error);
return { error: `Failed to get book details: ${error instanceof Error ? error.message : String(error)}` };
}
}
}
);
console.log('Registering get_user_library tool');
server.registerTool(
'get_user_library',
{
title: 'Get User Library',
description: 'Get a list of books in the user\'s library'
},
{
parameters: {
type: 'object',
properties: {
user_id: {
type: 'number',
description: 'Hardcover user ID (optional)',
},
},
},
execute: async ({ user_id }: { user_id?: number }) => {
console.log('Executing get_user_library', { user_id });
try {
const books = await client.getUserLibrary(user_id);
console.log('User library retrieved', { count: books.length });
return books;
} catch (error) {
console.error('Error getting user library:', error);
return { error: `Failed to get user library: ${error instanceof Error ? error.message : String(error)}` };
}
}
}
);
console.log('Connecting server to transport');
await server.connect(transport);
console.log('Server connected');
return;
} catch (error) {
console.error('Error in MCP handler:', error);
res.status(500).json({ error: `Server error: ${error instanceof Error ? error.message : String(error)}` });
return;
}
} else {
console.log('Method not allowed:', req.method);
res.status(405).json({ error: 'Method not allowed' });
return;
}
}
