import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
import {
setSubscriptionHandlers,
stopSimulatedResourceUpdates,
} from "../resources/subscriptions.js";
import { registerConditionalTools, registerTools } from "../tools/index.js";
import { registerResources, readInstructions } from "../resources/index.js";
import { registerPrompts } from "../prompts/index.js";
import { stopSimulatedLogging } from "./logging.js";
import { syncRoots } from "./roots.js";
// Server Factory response
export type ServerFactoryResponse = {
server: McpServer;
cleanup: (sessionId?: string) => void;
};
/**
* Server Factory
*
* This function initializes a `McpServer` with specific capabilities and instructions,
* registers tools, resources, and prompts, and configures resource subscription handlers.
*
* @returns {ServerFactoryResponse} An object containing the server instance, and a `cleanup`
* function for handling server-side cleanup when a session ends.
*
* Properties of the returned object:
* - `server` {Object}: The initialized server instance.
* - `cleanup` {Function}: Function to perform cleanup operations for a closing session.
*/
export const createServer: () => ServerFactoryResponse = () => {
// Read the server instructions
const instructions = readInstructions();
// Create the server
const server = new McpServer(
{
name: "mcp-servers/everything",
title: "Everything Reference Server",
version: "2.0.0",
},
{
capabilities: {
tools: {
listChanged: true,
},
prompts: {
listChanged: true,
},
resources: {
subscribe: true,
listChanged: true,
},
logging: {},
},
instructions,
}
);
// Register the tools
registerTools(server);
// Register the resources
registerResources(server);
// Register the prompts
registerPrompts(server);
// Set resource subscription handlers
setSubscriptionHandlers(server);
// Perform post-initialization operations
server.server.oninitialized = async () => {
// Register conditional tools now that client capabilities are known.
// This finishes before the `notifications/initialized` handler finishes.
registerConditionalTools(server);
// Sync roots if the client supports them.
// This is delayed until after the `notifications/initialized` handler finishes,
// otherwise, the request gets lost.
const sessionId = server.server.transport?.sessionId;
setTimeout(() => syncRoots(server, sessionId), 350);
};
// Return the ServerFactoryResponse
return {
server,
cleanup: (sessionId?: string) => {
// Stop any simulated logging or resource updates that may have been initiated.
stopSimulatedLogging(sessionId);
stopSimulatedResourceUpdates(sessionId);
},
} satisfies ServerFactoryResponse;
};
