Using SOCKS proxy, but the 'socksio' package is not installed.

Describe the bug
When I configure the use of fetch in cursor mcp, the configuration takes effect, but when fetch is triggered, an error always occurs：Using SOCKS proxy, but the 'socksio' package is not installed. Make sure to install httpx using pip install httpx[socks].

To Reproduce
Steps to reproduce the behavior:
cursor mcp config:

{
  "mcpServers": {
    "brave-search": {
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-brave-search"],
      "env": {
        "BRAVE_API_KEY": "xxxxx"
      }
    },
    "fetch": {
      "command": "uvx",
      "args": ["mcp-server-fetch"]
    }
  }
}

Expected behavior
My device has already installed uv, and the error still exists after performing the following operations:

1. uv venv

2. source .venv/bin/activate

3. uv pip install "httpx[socks]"

Similarly, I also tried using brew install pipx, pipx install "httpx[socks]", but the error still exists.

Logs
If applicable, add logs to help explain your problem.

Additional context
Add any other context about the problem here.

Start with the mcp-server-fetch command launched by uvx and verify which environment supplies its httpx dependency. Reproduce the SOCKS configuration from the issue and trace why installing httpx[socks] in a separate virtual environment does not affect that command. Done means the fetch server runs without the socksio error.