simple-init-service/simple-init-service.cjs

MCP server for semantic codebase search using Transformers.js

#!/usr/bin/env node

/**
 * Minimal MCP server implementation
 * - Content-Length framing
 * - Responds to 'initialize' method
 */

console.log("[mcp-server] MCP server started and waiting for commands...");

function sendMessage(msg) {
  const json = JSON.stringify(msg);
  const contentLength = Buffer.byteLength(json, 'utf8');
  const frame = `Content-Length: ${contentLength}\r\n\r\n${json}`;
  process.stdout.write(frame);
}

process.stdin.on('data', (chunk) => {
  let buffer = chunk;
  while (true) {
    const headerEnd = buffer.indexOf('\r\n\r\n');
    if (headerEnd === -1) break;
    const header = buffer.slice(0, headerEnd).toString('utf8');
    const m = header.match(/Content-Length:\s*(\d+)/i);
    if (!m) {
      buffer = buffer.slice(headerEnd + 4);
      continue;
    }
    const contentLength = parseInt(m[1], 10);
    const total = headerEnd + 4 + contentLength;
    if (buffer.length < total) break;
    const body = buffer.slice(headerEnd + 4, total).toString('utf8');
    buffer = buffer.slice(total);
    let message;
    try {
      message = JSON.parse(body);
    } catch (err) {
      continue;
    }
    if (message.method === 'initialize') {
      sendMessage({
        jsonrpc: '2.0',
        id: message.id,
        result: {
          capabilities: {},
          serverInfo: { name: 'mcp-server', version: '1.0.0' }
        }
      });
    }
  }
});