/** * Declares one extension capability, `com.example/feature-flags`, with a small * settings object. The entry is advertised to every peer — by the `initialize` * result on legacy connections and by `server/discover` on modern ones. * * One binary, either transport — selected by `--http --port ` (defaults to * stdio). See `examples/CONTRIBUTING.md` for the canonical shape. */ import { createServer } from 'node:http'; import { parseExampleArgs } from '@mcp-examples/shared'; import { toNodeHandler } from '@modelcontextprotocol/node'; import { createMcpHandler, McpServer } from '@modelcontextprotocol/server'; import { serveStdio } from '@modelcontextprotocol/server/stdio'; function buildServer(): McpServer { const mcp = new McpServer({ name: 'extension-capabilities-server', version: '1.0.0' }); // Declare the extension and its settings before connecting. mcp.server.registerCapabilities({ extensions: { 'com.example/feature-flags': { flags: ['dark-mode', 'beta-search'] } } }); return mcp; } const { transport, port } = parseExampleArgs(); if (transport === 'stdio') { void serveStdio(buildServer); console.error('[server] serving over stdio'); } else { const handler = createMcpHandler(buildServer); createServer(toNodeHandler(handler)).listen(port, () => { console.error(`[server] listening on http://127.0.0.1:${port}/mcp`); }); }