context7 MCP fails to connect with "Connection closed" error

[RedwindA]

What happened?

The context7 MCP fails to initialize and connect, resulting in "Connection closed" errors in the logs. Other configured MCPs (like the github MCP) work correctly with the same LibreChat deployment. The context7 MCP command itself works when executed directly in the terminal or VS Code Cline Extension

Version Information

150116e

Steps to Reproduce

1. Deploy LibreChat using the npm method.
2. Configure MCP with the provided configuration including both github and context7 MCPs.
3. Start LibreChat.
4. Observe the logs for errors related to the context7 MCP.

What browsers are you seeing the problem on?

Firefox

Relevant log output

MCP Configuration used:

mcpServers:
  github:
    type: stdio
    command: /usr/local/bin/github-mcp-server
    env:
      GITHUB_PERSONAL_ACCESS_TOKEN: redacted
    args:
      - stdio
  context7:
    command: /root/.nvm/versions/node/v22.14.0/bin/npx
    stderr: inherit
    initTimeout: 10000
    args:
      - -y
      - "@upstash/context7-mcp@latest"

{"code":-32000,"level":"error","message":"[MCP][context7] Failed to connect after 3 attempts MCP error -32000: Connection closed","name":"McpError","stack":"McpError: MCP error -32000: Connection closed\n    at dn._onclose (/root/LibreChat-npm/packages/mcp/dist/index.js:1:71448)\n    at _transport.onclose (/root/LibreChat-npm/packages/mcp/dist/index.js:1:71053)\n    at ChildProcess.<anonymous> (/root/LibreChat-npm/packages/mcp/dist/index.js:1:97799)\n    at ChildProcess.emit (node:events:518:28)\n    at maybeClose (node:internal/child_process:1101:16)\n    at Socket.<anonymous> (node:internal/child_process:456:11)\n    at Socket.emit (node:events:518:28)\n    at Pipe.<anonymous> (node:net:351:12)"}
{"code":-32000,"level":"error","message":"[MCP][context7] Initialization failed MCP error -32000: Connection closed","name":"McpError","stack":"McpError: MCP error -32000: Connection closed\n    at dn._onclose (/root/LibreChat-npm/packages/mcp/dist/index.js:1:71448)\n    at _transport.onclose (/root/LibreChat-npm/packages/mcp/dist/index.js:1:71053)\n    at ChildProcess.<anonymous> (/root/LibreChat-npm/packages/mcp/dist/index.js:1:97799)\n    at ChildProcess.emit (node:events:518:28)\n    at maybeClose (node:internal/child_process:1101:16)\n    at Socket.<anonymous> (node:internal/child_process:456:11)\n    at Socket.emit (node:events:518:28)\n    at Pipe.<anonymous> (node:net:351:12)"}
{"code":-32000,"level":"error","message":"[MCP][context7] Connection failed: MCP error -32000: Connection closed","name":"McpError","stack":"McpError: MCP error -32000: Connection closed\n    at dn._onclose (/root/LibreChat-npm/packages/mcp/dist/index.js:1:71448)\n    at _transport.onclose (/root/LibreChat-npm/packages/mcp/dist/index.js:1:71053)\n    at ChildProcess.<anonymous> (/root/LibreChat-npm/packages/mcp/dist/index.js:1:97799)\n    at ChildProcess.emit (node:events:518:28)\n    at maybeClose (node:internal/child_process:1101:16)\n    at Socket.<anonymous> (node:internal/child_process:456:11)\n    at Socket.emit (node:events:518:28)\n    at Pipe.<anonymous> (node:net:351:12)"}
{"code":-32000,"level":"error","message":"[MCP][context7] Connection failed: MCP error -32000: Connection closed","name":"McpError","stack":"McpError: MCP error -32000: Connection closed\n    at dn._onclose (/root/LibreChat-npm/packages/mcp/dist/index.js:1:71448)\n    at _transport.onclose (/root/LibreChat-npm/packages/mcp/dist/index.js:1:71053)\n    at ChildProcess.<anonymous> (/root/LibreChat-npm/packages/mcp/dist/index.js:1:97799)\n    at ChildProcess.emit (node:events:518:28)\n    at maybeClose (node:internal/child_process:1101:16)\n    at ChildProcess._handle.onexit (node:internal/child_process:304:5)"}
{"code":-32000,"level":"error","message":"[MCP][context7] Connection failed: MCP error -32000: Connection closed","name":"McpError","stack":"McpError: MCP error -32000: Connection closed\n    at dn._onclose (/root/LibreChat-npm/packages/mcp/dist/index.js:1:71448)\n    at _transport.onclose (/root/LibreChat-npm/packages/mcp/dist/index.js:1:71053)\n    at ChildProcess.<anonymous> (/root/LibreChat-npm/packages/mcp/dist/index.js:1:97799)\n    at ChildProcess.emit (node:events:518:28)\n    at maybeClose (node:internal/child_process:1101:16)\n    at Socket.<anonymous> (node:internal/child_process:456:11)\n    at Socket.emit (node:events:518:28)\n    at Pipe.<anonymous> (node:net:351:12)"}
{"code":-32000,"level":"error","message":"[MCP][context7] Failed to connect after 3 attempts MCP error -32000: Connection closed","name":"McpError","stack":"McpError: MCP error -32000: Connection closed\n    at dn._onclose (/root/LibreChat-npm/packages/mcp/dist/index.js:1:71448)\n    at _transport.onclose (/root/LibreChat-npm/packages/mcp/dist/index.js:1:71053)\n    at ChildProcess.<anonymous> (/root/LibreChat-npm/packages/mcp/dist/index.js:1:97799)\n    at ChildProcess.emit (node:events:518:28)\n    at maybeClose (node:internal/child_process:1101:16)\n    at Socket.<anonymous> (node:internal/child_process:456:11)\n    at Socket.emit (node:events:518:28)\n    at Pipe.<anonymous> (node:net:351:12)"}
{"code":-32000,"level":"error","message":"[MCP][context7] Initialization failed MCP error -32000: Connection closed","name":"McpError","stack":"McpError: MCP error -32000: Connection closed\n    at dn._onclose (/root/LibreChat-npm/packages/mcp/dist/index.js:1:71448)\n    at _transport.onclose (/root/LibreChat-npm/packages/mcp/dist/index.js:1:71053)\n    at ChildProcess.<anonymous> (/root/LibreChat-npm/packages/mcp/dist/index.js:1:97799)\n    at ChildProcess.emit (node:events:518:28)\n    at maybeClose (node:internal/child_process:1101:16)\n    at Socket.<anonymous> (node:internal/child_process:456:11)\n    at Socket.emit (node:events:518:28)\n    at Pipe.<anonymous> (node:net:351:12)"}

Code of Conduct

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

[danny-avila]

it will totally depend on your environment, and where node/npx can be accessed from. For example, it works using both npm and docker with the following:

mcpServers:
  context7:
    command: npx
    args:
      - -y
      - "@upstash/context7-mcp@latest"

npm logs:

2025-04-23T21:22:40.038Z info: [MCP][context7] Available tools: resolve-library-id, get-library-docs
2025-04-23T21:22:40.038Z info: [MCP] Initialized 1/1 app-level server(s)
2025-04-23T21:22:40.038Z info: [MCP][context7] ✓ Initialized
2025-04-23T21:22:40.038Z info: [MCP] All app-level servers initialized successfully
2025-04-23T21:22:40.038Z debug: [MCP][context7] Transport sending: {"method":"tools/list","jsonrpc":"2.0","id":2}

docker logs:

2025-04-23 17:27:41 2025-04-23T21:27:41.411Z debug: [MCP][context7] Transport sending: {"method":"notifications/initialized","jsonrpc":"2.0"}
2025-04-23 17:27:41 2025-04-23T21:27:41.411Z info: [MCP][context7] Capabilities: {"tools":{"listChanged":true}}
2025-04-23 17:27:41 2025-04-23T21:27:41.411Z debug: [MCP][context7] Transport sending: {"method":"tools/list","jsonrpc":"2.0","id":1}
2025-04-23 17:27:41 2025-04-23T21:27:41.414Z info: [MCP][context7] Available tools: resolve-library-id, get-library-docs
2025-04-23 17:27:41 2025-04-23T21:27:41.414Z info: [MCP] Initialized 1/1 app-level server(s)
2025-04-23 17:27:41 2025-04-23T21:27:41.414Z info: [MCP][context7] ✓ Initialized

[shaununderwood]

Suffering the same issue, I swapped out npx for bunx and it worked perfectly. v20 and v22 of node installed via nvm yielded a ERR_MODULE_NOT_FOUND on zod-to-json-schema/dist/esm/index.js

Updated mcp server json:

mcpServers:
  context7:
    command: bunx
    args:
      - -y
      - "@upstash/context7-mcp@latest"

[RedwindA]

I found the cause of the error: I used systemd to start LibreChat, but I didn't configure the correct PATH environment variables in systemd, which caused the program to fail to find npx. After fixing it, LibreChat can used context7