ElysiaSAFE

An implementation of the Model Context Protocol (MCP) server using Bun and the Elysia web framework. This project enables you to create high-performance MCP servers that expose resources, tools, and prompts to LLMs through a standardized interface.

Features

• Server-Sent Events (SSE) transport implementation for Bun and Elysia
• Complete MCP protocol support with resources, tools, and prompts
• High-performance thanks to Bun's JavaScript runtime
• TypeScript support with proper type definitions
• Easy-to-use API for creating MCP-compatible servers

Prerequisites

• Bun installed on your system
• Basic familiarity with TypeScript and Elysia

Installation

# Clone the repository
git clone 
cd mcp-server

# Install dependencies
bun install

Usage

Starting the server

# Start the server
bun start

# Start with hot reloading for development
bun dev

Building for production

# Build for production
bun run build

This will create a minified Node.js-compatible build in the dist directory.

Development

Project Structure

• src/index.ts - Main entry point for the server
• src/SSEElysiaTransport.ts - SSE transport implementation for Bun and Elysia

Creating an MCP Server

import { McpServer, ResourceTemplate } from "@modelcontextprotocol/sdk/server/mcp.js";
import { z } from "zod";
import { SSEElysiaTransport } from "./SSEElysiaTransport";
import { Elysia } from "elysia";

// Create MCP server
const server = new McpServer({
name: "my-mcp-server",
version: "1.0.0"
});

// Add resources, tools, and prompts
server.resource(
"example",
"example://resource",
async (uri) => ({
contents: [{
uri: uri.href,
text: "Example resource content"
}]
})
);

// Create Elysia app
const app = new Elysia()
.get("/", () => "MCP Server")
.get("/sse", async (context) => {
try {
// Create transport