MCP GitHub Server: 'fetch is not defined' error when executing any tool

[circuitfive]

Issue Description

When attempting to use the GitHub MCP server via NPX installation, all tool executions fail with the error: MCP error -32603: fetch is not defined. This appears to be due to a missing dependency on node-fetch in the published package.

Steps to Reproduce

1. Install the server using the NPX method as documented in the README:

{
  "mcpServers": {
    "github": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-github"
      ],
      "env": {
        "GITHUB_PERSONAL_ACCESS_TOKEN": "<YOUR_TOKEN>"
      }
    }
  }
}

2. Start the server (server starts successfully)
3. Attempt to execute any tool (e.g., get_file_contents)
4. Observe the error: MCP error -32603: fetch is not defined

Environment

• Operating System: macOS Sonoma
• Node.js version: v20.19.0
• IDE: VSCode with Cursor extension
• Cursor version: 3.8.2
• MCP integration: Using Cline MCP settings with default configuration

Expected Behavior

Tools should execute successfully without dependency errors.

Actual Behavior

All tool executions fail with fetch is not defined error, indicating the server package is missing the node-fetch dependency.

Suggested Fix

Consider adding node-fetch as a dependency in the package.json file for the GitHub MCP server.

Additional Notes

This issue was not present in the repository's issue tracker as of March 25, 2025. The server process runs without startup errors, but fails when attempting to execute any tool.

[zudsniper]

Seconded.

[utkarsh-dixit]

This is a common issue we faced while trying to make https://mcp.composio.dev work with clients that only support stdio servers like Claude Desktop. The problem here is, since these clients are just spawning up the npx command without any context of shell, it is picking a random node version from your system that doesn't have node-fetch in-built.

From your Environment config, you are saying nodejs version is - v20.19.0 but it is picking some version older than node 16 that is installed in your system. If you are using nvm or something, just quickly try deleting and the older version and it should work

[kr-kwteam]

이것은 Claude Desktop과 같은 stdio 서버만 지원하는 클라이언트에서 https://mcp.composio.dev를 작동 시키려고 시도하는 동안 우리가 마주친 일반적인 문제입니다 . 여기서 문제는 이러한 클라이언트가 셸의 컨텍스트 없이 명령을 생성하기 때문에 내장 npx되지 않은 시스템에서 임의의 노드 버전을 선택한다는 것입니다 .node-fetch

환경 구성에서 nodejs 버전이 - v20.19.0이라고 말하고 있지만 시스템에 설치된 node 16보다 이전 버전을 선택하고 있습니다. nvm또는 무언가를 사용하고 있다면 간단히 이전 버전을 삭제해 보세요. 그러면 작동할 것입니다.

@utkarsh-dixit That was really helpful. Thank you.

[circuitfive]

Thank you for the suggestion @utkarsh-dixit, it didn't seem to make a difference for me. Here's the output from nvm ls:

~ nvm ls
->     v20.19.0
         system
default -> 20 (-> v20.19.0)
iojs -> N/A (default)
unstable -> N/A (default)
node -> stable (-> v20.19.0) (default)
stable -> 20.19 (-> v20.19.0) (default)
lts/* -> lts/jod (-> N/A)
lts/argon -> v4.9.1 (-> N/A)
lts/boron -> v6.17.1 (-> N/A)
lts/carbon -> v8.17.0 (-> N/A)
lts/dubnium -> v10.24.1 (-> N/A)
lts/erbium -> v12.22.12 (-> N/A)
lts/fermium -> v14.21.3 (-> N/A)
lts/gallium -> v16.20.2 (-> N/A)
lts/hydrogen -> v18.20.7 (-> N/A)
lts/iron -> v20.19.0
lts/jod -> v22.14.0 (-> N/A)

Any clues there?

[Zamoca42]

In my case, npm install -g node-fetch solved the problem.
It's also worth trying to unify the default version of nvm to system.
like this: nvm alias default system

[olaservo]

This PR added a polyfill for node-fetch that was meant to address scenarios where node-fetch wasn't already supported: https://github.com/modelcontextprotocol/servers/pull/603/files

I'm curious if this issue still happens after specifying @modelcontextprotocol/server-github@latest when installing with npx?

[cliffhall]

Deprecation Notice: Development for server-github has been moved to GitHub in the http://github.com/github/github-mcp-server repo. PRs to server-github in this repo are no longer being merged.

[wufei-png]

In my case, npm install -g node-fetch solved the problem. It's also worth trying to unify the default version of nvm to system. like this: nvm alias default system

solved