perplexity-mcp-server/dist/mcp-server/server.js

A Perplexity API Model Context Protocol (MCP) server that unlocks Perplexity's search-augmented AI capabilities for LLM agents. Features robust error handling, secure input validation, and transparent reasoning with the showThinking parameter. Built with

import { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js'; // Import McpServer
import { StdioServerTransport } from '@modelcontextprotocol/sdk/server/stdio.js';
import { config, environment } from '../config/index.js';
import { ErrorHandler } from '../utils/errorHandler.js';
import { logger } from '../utils/logger.js';
import { requestContextService } from "../utils/requestContext.js"; // Import the service
// Tool Registrations
import { registerPerplexitySearchTool } from './tools/perplexitySearch/index.js'; // Import the new search tool registration
/**
 * Creates, configures, and connects the main MCP server instance.
 * This function initializes the server with configuration values, registers
 * available resources and tools, and establishes communication via stdio.
 *
 * @async
 * @function createMcpServer
 * @returns {Promise<McpServer>} A promise that resolves with the configured and connected McpServer instance.
 * @throws {Error} Throws an error if critical failures occur during registration or connection.
 */
export const createMcpServer = async () => {
    const operationContext = { operation: 'ServerInitialization' };
    logger.info("Initializing MCP server...", operationContext);
    // Configure request context settings using the service
    requestContextService.configure({
        appName: config.mcpServerName,
        appVersion: config.mcpServerVersion,
        environment: environment
    });
    logger.debug("Request context service configured.", operationContext);
    // Create the server instance using McpServer
    const server = new McpServer({
        name: config.mcpServerName,
        version: config.mcpServerVersion,
    }, {
        capabilities: {
            // Capabilities are defined dynamically via registration functions below
            resources: {},
            tools: {},
        },
    });
    logger.debug("McpServer instance created.", { ...operationContext, serverName: config.mcpServerName });
    // Register resources and tools using their dedicated functions
    try {
        logger.info("Registering tools...", operationContext);
        // Pass the McpServer instance to the registration functions
        registerPerplexitySearchTool(server); // Register the new search tool - Changed from await as registration is sync
        logger.debug("Perplexity Search tool registered.", operationContext);
        logger.info("Tools registered successfully.", operationContext);
    }
    catch (registrationError) {
        // ErrorHandler within registration functions should handle specific logging/throwing
        // This catch block handles unexpected errors during the registration process itself
        logger.error("Critical error during resource/tool registration process", {
            ...operationContext,
            error: registrationError instanceof Error ? registrationError.message : String(registrationError),
            stack: registrationError instanceof Error ? registrationError.stack : undefined,
        });
        // Rethrow to halt server startup if registration fails critically
        throw registrationError;
    }
    // Connect the server using Stdio transport
    try {
        logger.info("Connecting server via Stdio transport...", operationContext);
        const transport = new StdioServerTransport();
        await server.connect(transport);
        logger.info(`${config.mcpServerName} connected successfully via stdio`, {
            ...operationContext,
            serverName: config.mcpServerName,
            version: config.mcpServerVersion
        });
    }
    catch (connectionError) {
        // Handle connection errors specifically
        ErrorHandler.handleError(connectionError, {
            operation: 'Server Connection',
            context: operationContext,
            critical: true,
            rethrow: true // Rethrow to allow the main startup process (in index.ts) to handle exit
        });
        // The line below won't be reached if rethrow is true, but needed for type safety if rethrow were false
        throw connectionError;
    }
    logger.info("MCP server initialization complete.", operationContext);
    return server;
};