npx-related mcp server failed to load on nvm env

[donghao1393]

Describe the bug
I am using fish on macos. Previously node was installed by brew and mcp on claude desktop works fine. but it's failed since I got node from fish verion nvm.

To Reproduce
Steps to reproduce the behavior:

$ brew uninstall node
$ fisher install jorgebucaran/nvm.fish
$ nvm use lts
$ node --version
  npm --version
  npx --version
v22.12.0
10.9.0
10.9.0
$ bash
bash-3.2$ node --version
v22.12.0
bash-3.2$ npm --version
10.9.0
bash-3.2$ npx --version
10.9.0
$ zsh
(base) donghao@Dongs-MacBook-Air ~ % node --version
v22.12.0
(base) donghao@Dongs-MacBook-Air ~ % npm --version
10.9.0
(base) donghao@Dongs-MacBook-Air ~ % npx --version
10.9.0

Expected behavior
mcp servers should be loaded successful.

Logs

2024-12-28T19:16:03.934Z [error] Error in MCP connection to server filesystem: Error: spawn npx ENOENT
2024-12-28T19:16:03.935Z [error] Could not start MCP server filesystem: Error: spawn npx ENOENT
2024-12-28T19:16:03.936Z [error] Error in MCP connection to server memory: Error: spawn npx ENOENT
2024-12-28T19:16:03.936Z [error] Could not start MCP server memory: Error: spawn npx ENOENT
2024-12-28T19:16:03.936Z [info] Connected to MCP server git!
2024-12-28T19:16:03.937Z [error] Error in MCP connection to server github: Error: spawn npx ENOENT
2024-12-28T19:16:03.937Z [error] Could not start MCP server github: Error: spawn npx ENOENT

Additional context
it resume to work after switching to brew version node

$ nvm uninstall lts
$ brew install node

[donghao1393]

same issue like:

• MCP Servers Don't Work with NVM #64

[donghao1393]

MCP Server Commands PATH Environment Investigation Report

Issue Description

The MCP Server Commands environment cannot directly access Node.js executables installed via nvm, unless they are symlinked to the /opt/homebrew/bin directory.

Current Workaround

Currently, we're using symbolic links to make Node.js commands accessible:

# Create symbolic links from nvm-installed Node.js to Homebrew bin directory
ln -s ~/.local/share/nvm/v22.12.0/bin/npx /opt/homebrew/bin/npx
ln -s ~/.local/share/nvm/v22.12.0/bin/npm /opt/homebrew/bin/npm
ln -s ~/.local/share/nvm/v22.12.0/bin/node /opt/homebrew/bin/node

# Verify the links
$ ls -l /opt/homebrew/bin/npx
lrwxr-xr-x@ 1 donghao  admin  48 Dec 29 10:50 /opt/homebrew/bin/npx -> /Users/donghao/.local/share/nvm/v22.12.0/bin/npx

While this workaround is functional, it's not an ideal solution as it requires manual intervention and maintenance.

Investigation Process

1. Initial Environment Analysis

Checked current shell and environment settings:

$ echo $0
/bin/sh

$ env
SHELL=/opt/homebrew/bin/fish
PATH=/Users/donghao/.npm/_npx/d597531c0c0615ae/node_modules/.bin:/node_modules/.bin:/Users/donghao/.local/share/nvm/v22.12.0/lib/node_modules/npm/node_modules/@npmcli/run-script/lib/node-gyp-bin:/usr/local/bin:/opt/homebrew/bin:/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin

2. Homebrew Path Investigation

Analyzed Homebrew's installation script to understand how it manages PATH:

1. Downloaded and examined the install script:

$ /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

2. Key findings from install.sh:

• For Apple Silicon Macs, uses /opt/homebrew as HOMEBREW_PREFIX
• Automatically adds itself to shell configuration files
• Uses brew shellenv to set up environment variables

3. Checked brew shellenv output:

$ brew shellenv
export HOMEBREW_PREFIX="/opt/homebrew";
export HOMEBREW_CELLAR="/opt/homebrew/Cellar";
export HOMEBREW_REPOSITORY="/opt/homebrew";
PATH="/opt/homebrew/bin:/opt/homebrew/sbin:$PATH"; export PATH;

3. Environment Configuration Attempts

1. Checked home directory location:

$ echo $HOME
/Users/donghao

2. Examined existing profile file:

$ cat ~/.profile
. "$HOME/.cargo/env"

3. Added nvm path to profile:

$ echo 'export PATH="/Users/donghao/.local/share/nvm/v22.12.0/bin:$PATH"' >> ~/.profile

4. Checked Cargo's environment setup:

$ cat ~/.cargo/env
#!/bin/sh
case ":${PATH}:" in
    *:"$HOME/.cargo/bin":*)
        ;;
    *)
        export PATH="$HOME/.cargo/bin:$PATH"
        ;;
esac

4. Configuration Verification

1. Modified the ~/.profile file to include both nvm and cargo paths:

# Current content of ~/.profile
export PATH="/Users/donghao/.local/share/nvm/v22.12.0/bin:$PATH"
. "$HOME/.cargo/env"

2. Tested direct PATH access:

$ echo $PATH
# Shows PATH without new additions

3. Tested profile sourcing:

$ source ~/.profile
$ echo $PATH
/Users/donghao/.cargo/bin:/Users/donghao/.local/share/nvm/v22.12.0/bin:/Users/donghao/.npm/_npx/d597531c0c0615ae/node_modules/.bin:/node_modules/.bin:/Users/donghao/.local/share/nvm/v22.12.0/lib/node_modules/npm/node_modules/@npmcli/run-script/lib/node-gyp-bin:/usr/local/bin:/opt/homebrew/bin:/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin

Technical Findings

1. The service environment:

   • Runs under /bin/sh
   • Has access to /opt/homebrew/bin by default
   • Does not appear to load user shell configurations

2. Shell configuration files:

   • .profile modifications are not automatically loaded
   • Homebrew's path is consistently available
   • Similar tools (like Rust/Cargo) use comparable PATH modification approaches

Questions for Developers

1. Service Configuration:

   • How is the MCP Server Commands service initiated?
   • Is there a way to load user environment configurations at service startup?
   • Can we configure additional PATH entries at the service level?

2. Environment Management:

   • Is there a preferred method for extending PATH in this environment?
   • Should there be a standardized way to handle tool-specific paths?

Possible Solutions

1. Service-level configuration:

   • Add capability to specify additional PATH entries in service configuration
   • Implement proper environment loading during service startup

2. Standardized path management:

   • Create a central location for tool paths
   • Implement automatic PATH management for installed tools

3. Documentation improvement:

   • Document the current limitations
   • Provide clear instructions for path management

Next Steps

We seek developers' input on:

1. The preferred approach for handling tool paths
2. Whether environment loading can be improved
3. If any of the proposed solutions align with the project's direction