index.ts•3.29 kB
/**
* Fetch Browser
*
* An MCP server that acts as a browser, providing:
* - Web content fetching in multiple formats (HTML, JSON, Text, Markdown)
* - Smart Google search results parsing
* - Error handling and retries
* - Rate limiting protection
*/
import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
import { registerUrlFetcherTool } from "./url-fetcher.js";
import { registerGoogleSearchTool } from "./google-search.js";
/**
* Create a new MCP server instance with full capabilities
*/
const server = new McpServer({
name: "fetch-browser",
version: "0.1.0",
capabilities: {
tools: {
fetch_url: {
description: "Fetch content from a URL with proper error handling and response processing",
parameters: {
url: "The URL to fetch",
responseType: "Expected response type (text, json, html, markdown)",
timeout: "Request timeout in milliseconds (optional)"
}
},
google_search: {
description: "Execute a Google search and return results in various formats",
parameters: {
query: "The search query to execute",
responseType: "Expected response type (text, json, html, markdown)",
maxResults: "Maximum number of results to return (optional)",
topic: "Type of search to perform (web or news)"
}
}
},
resources: {},
prompts: {},
streaming: true
}
});
/**
* Helper function to send log messages to the client
*/
function logMessage(level: 'info' | 'warn' | 'error', message: string) {
console.error(`[${level.toUpperCase()}] ${message}`);
}
/**
* Set up error handling for the server
*/
process.on('uncaughtException', (error: Error) => {
logMessage('error', `Uncaught error: ${error.message}`);
console.error('Server error:', error);
});
// Register tools
try {
registerUrlFetcherTool(server);
registerGoogleSearchTool(server);
logMessage('info', 'Successfully registered tools');
} catch (error) {
logMessage('error', `Failed to register tools: ${error instanceof Error ? error.message : 'Unknown error'}`);
process.exit(1);
}
/**
* Set up proper cleanup on process termination
*/
async function cleanup() {
try {
await server.close();
logMessage('info', 'Server shutdown completed');
} catch (error) {
logMessage('error', `Error during shutdown: ${error instanceof Error ? error.message : 'Unknown error'}`);
} finally {
process.exit(0);
}
}
// Handle termination signals
process.on('SIGTERM', cleanup);
process.on('SIGINT', cleanup);
/**
* Main server startup function
*/
async function main() {
try {
// Set up communication with the MCP host using stdio transport
const transport = new StdioServerTransport();
await server.connect(transport);
logMessage('info', 'Fetch Browser started successfully');
console.error('Fetch Browser running on stdio transport');
} catch (error) {
logMessage('error', `Failed to start server: ${error instanceof Error ? error.message : 'Unknown error'}`);
process.exit(1);
}
}
// Start the server
main().catch((error) => {
console.error('Fatal error in main():', error);
process.exit(1);
});