#!/usr/bin/env node
/**
* MCP Server: Greeting Server
*
* A simple MCP server demonstrating TOOLs and RESOURCEs.
* Tutorial companion for: "Build Your Own MCP Server (TypeScript)"
* Channel: Gheware DevOps AI
*
* Features:
* - TOOL: create_greeting - Generate personalized greetings
* - RESOURCE: greeting://templates - List available greeting styles
*/
import { Server } from "@modelcontextprotocol/sdk/server/index.js";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
import {
CallToolRequestSchema,
ListToolsRequestSchema,
ListResourcesRequestSchema,
ReadResourceRequestSchema,
ErrorCode,
McpError,
} from "@modelcontextprotocol/sdk/types.js";
// ============================================
// MCP SERVER SETUP
// ============================================
const server = new Server(
{
name: "greeting-server",
version: "1.0.0",
},
{
capabilities: {
tools: {},
resources: {},
},
}
);
// ============================================
// TOOLS: Define operations the AI can perform
// ============================================
server.setRequestHandler(ListToolsRequestSchema, async () => {
return {
tools: [
{
name: "create_greeting",
description: "Create a personalized greeting message",
inputSchema: {
type: "object" as const,
properties: {
name: {
type: "string",
description: "The name of the person to greet",
},
style: {
type: "string",
enum: ["formal", "casual", "excited"],
description: "The style of greeting (formal, casual, or excited)",
},
},
required: ["name"],
},
},
],
};
});
server.setRequestHandler(CallToolRequestSchema, async (request) => {
const { name, arguments: args } = request.params;
if (name === "create_greeting") {
const { name: personName, style = "casual" } = args as {
name: string;
style?: "formal" | "casual" | "excited";
};
const greetings: Record<string, string> = {
formal: `Good day, ${personName}. It is a pleasure to meet you.`,
casual: `Hi ${personName}! How's it going?`,
excited: `Hey ${personName}!!! So awesome to see you! 🎉`,
};
const greeting = greetings[style] || greetings.casual;
return {
content: [
{
type: "text" as const,
text: greeting,
},
],
};
}
throw new McpError(ErrorCode.MethodNotFound, `Unknown tool: ${name}`);
});
// ============================================
// RESOURCES: Expose data for the AI to read
// ============================================
server.setRequestHandler(ListResourcesRequestSchema, async () => {
return {
resources: [
{
uri: "greeting://templates",
name: "Greeting Templates",
description: "Available greeting styles and examples",
mimeType: "text/plain",
},
],
};
});
server.setRequestHandler(ReadResourceRequestSchema, async (request) => {
const { uri } = request.params;
if (uri === "greeting://templates") {
return {
contents: [
{
uri,
mimeType: "text/plain",
text: `Available Greeting Styles:
1. formal - Professional, polite greeting
Example: "Good day, John. It is a pleasure to meet you."
2. casual - Friendly, everyday greeting
Example: "Hi John! How's it going?"
3. excited - Enthusiastic, celebratory greeting
Example: "Hey John!!! So awesome to see you! 🎉"
Usage: Ask Claude to "greet [name] in [style] style"`,
},
],
};
}
throw new McpError(ErrorCode.InvalidRequest, `Unknown resource: ${uri}`);
});
// ============================================
// START THE SERVER
// ============================================
async function main() {
const transport = new StdioServerTransport();
await server.connect(transport);
console.error("MCP Greeting Server running on stdio");
}
main().catch((error) => {
console.error("Fatal error:", error);
process.exit(1);
});
