sse mode doesn't seem to work

[heapbytes]

Hi,
I dont think SSE works as intended, when my librechat try it over /sse, pentest-mcp fails.
Ref -

Tried with curl localhost:8888/sse for testing.

└─$ MCP_TRANSPORT=sse MCP_SERVER_PORT=8888 pentest-mcp
Node.js process PATH: /home/mcp/.local/bin:/usr/share/pyenv/shims:/usr/share/pyenv/bin:/usr/local/sbin:/usr/sbin:/sbin:/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games
Initializing Pentest MCP Server with sse transport...
Starting SSE transport...
Pentest MCP Server shutdown.
MCP SSE server running at http://0.0.0.0:8888/sse
Messages endpoint at http://0.0.0.0:8888/messages
Health check at http://0.0.0.0:8888/health
GET /sse - Client connecting to SSE stream
node:_http_server:344
    throw new ERR_HTTP_HEADERS_SENT('write');
          ^

Error [ERR_HTTP_HEADERS_SENT]: Cannot write headers after they are sent to the client
    at ServerResponse.writeHead (node:_http_server:344:11)
    at SSEServerTransport.start (file:///usr/local/lib/node_modules/pentest-mcp/node_modules/@modelcontextprotocol/sdk/dist/esm/server/sse.js:56:18)
    at Server.connect (file:///usr/local/lib/node_modules/pentest-mcp/node_modules/@modelcontextprotocol/sdk/dist/esm/shared/protocol.js:96:31)
    at McpServer.connect (file:///usr/local/lib/node_modules/pentest-mcp/node_modules/@modelcontextprotocol/sdk/dist/esm/server/mcp.js:30:34)
    at file:///usr/local/lib/node_modules/pentest-mcp/dist/index.js:1412:30
    at Layer.handle [as handle_request] (/usr/local/lib/node_modules/pentest-mcp/node_modules/express/lib/router/layer.js:95:5)
    at next (/usr/local/lib/node_modules/pentest-mcp/node_modules/express/lib/router/route.js:149:13)
    at Route.dispatch (/usr/local/lib/node_modules/pentest-mcp/node_modules/express/lib/router/route.js:119:3)
    at Layer.handle [as handle_request] (/usr/local/lib/node_modules/pentest-mcp/node_modules/express/lib/router/layer.js:95:5)
    at /usr/local/lib/node_modules/pentest-mcp/node_modules/express/lib/router/index.js:284:15 {
  code: 'ERR_HTTP_HEADERS_SENT'
}

Node.js v20.19.2