env placeholder {{LIBRECHAT_USER_ID}} not replaced in stdio MCP servers

[gihun123]

What happened?

The {{LIBRECHAT_USER_ID}} placeholder in env field is not being replaced for stdio type MCP servers, while ${ENV_VAR} placeholders work correctly.

Version Information

0.8.0

Steps to Reproduce

librechat.yaml

mcpServers:
  my-mcp-server: 
    type: stdio
    command: node
    args: 
      - /app/mcp-server/index.js
    env:
      TEST_ENV: "${HOME}"  
      USER_ID: "{{LIBRECHAT_USER_ID}}"

index.js

import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";

const server = new McpServer({
  name: "my-mcp-server",
  version: "1.1.0"
});

console.error(process.env);

async function main() {
  const transport = new StdioServerTransport();
  await server.connect(transport);
}

main().catch((error) => {
  process.exit(1);
});

What browsers are you seeing the problem on?

No response

Relevant log output

{
  HOME: '/root',
  PATH: '/app/node_modules/.bin:/node_modules/.bin:/usr/local/lib/node_modules/npm/node_modules/@npmcli/run-script/lib/node-gyp-bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin',
  TEST_ENV: '/root',
  USER_ID: '{{LIBRECHAT_USER_ID}}'
}

Screenshots

No response

Code of Conduct

• I agree to follow this project's Code of Conduct

[danny-avila]

STDIO servers are initialized on startup by default and the MCP connection is shared so individual MCP connections cannot inform running the script so it's already ran at startup.

Try this:

mcpServers:
  my-mcp-server: 
    startup: false
    type: stdio
    command: node
    args: 
      - /app/mcp-server/index.js
    env:
      TEST_ENV: "${HOME}"  
      USER_ID: "{{LIBRECHAT_USER_ID}}"