Function processRequest

packages/mcp/src/handler.ts:128–194

* Create a fresh McpServer for each request and process a single JSON-RPC message. * * For non-initialize requests we fast-forward the server through the MCP * initialization handshake (using an internal fake initialize) before dispatching * the real message. This keeps the handler stateless whi

(
  context: Parameters<typeof createMcpServer>[0],
  message: JSONRPCMessage,
  isInitialize = false,
)

 * internal state machine.
 */
async function processRequest(
  context: Parameters<typeof createMcpServer>[0],
  message: JSONRPCMessage,
  isInitialize = false,
): Promise<JSONRPCMessage> {
  if ('method' in message && message.method === 'tools/call' && 'params' in message) {
    const { name, arguments: args } = (message.params ?? {}) as { name?: string; arguments?: unknown };
    logger.info(
      {
        tool: name,
        params: args,
        organizationId: context.organizationId,
        projectId: context.projectId,
        clientType: context.clientType,
      },
      'MCP tool call',
    );
  }
  const [clientTransport, serverTransport] = InMemoryTransport.createLinkedPair();
  const server = createMcpServer(context);
  await server.connect(serverTransport);

  if (!isInitialize) {
    // Fast-forward: send a fake initialize so the server enters its ready state
    await new Promise<void>((resolve, reject) => {
      clientTransport.onmessage = () => resolve();
      clientTransport
        .send({
          jsonrpc: '2.0',
          id: '__mcp_init__',
          method: 'initialize',
          params: {
            protocolVersion: MCP_PROTOCOL_VERSION,
            capabilities: {},
            clientInfo: { name: 'mcp-proxy', version: '0' },
          },
        })
        .catch(reject);
    });
    // Notify the server that initialization is complete (no response expected)
    await clientTransport.send({
      jsonrpc: '2.0',
      method: 'notifications/initialized',
    });
  }

  const start = Date.now();
  const response = await new Promise<JSONRPCMessage>((resolve, reject) => {
    clientTransport.onmessage = resolve;
    clientTransport.send(message).catch(reject);
  });

  if ('method' in message && message.method === 'tools/call') {
    const { name } = (('params' in message && message.params) ?? {}) as { name?: string };
    const isError = 'result' in response && (response.result as { isError?: boolean })?.isError;
    logger.info(
      {
        tool: name,