akaiserg/hello-world-mcp

hello-world-mcp

Description

A simple Python project that prints a hello message.

Requirements

• Python 3.11 or higher

Setup

Create and activate a virtual environment (recommended):

python3 -m venv .venv
source .venv/bin/activate

Install dependencies

If you need to install the mcp[cli] extra, use quotes to avoid shell errors:

uv add 'mcp[cli]'

Note: The quotes are required in zsh to prevent bracket expansion errors.

How to Run

Run the client

client.py connects to the weather.py server using stdio, lists available tools, and calls the get_weather tool with a sample location.

python client.py

Or run the client with uv

Running with uv ensures all dependencies are managed by uv:

uv run client.py

Using the MCP CLI

To run the weather.py server in development mode with live reloading and the MCP Inspector UI, use:

mcp dev weather.py

This will start your MCP server locally and open the Inspector at http://localhost:6274 for testing and debugging your tools.

Example Host Configuration

If you need to configure your host/server entry (e.g., for Claude Desktop or a similar tool), use the following example:

"weather": {
  "command": "uv",
  "args": [
    "--directory",
    "/path",
    "run",
    "weather.py"
  ]
}

This configuration tells the host to use uv to run weather.py from your project directory, ensuring all dependencies are available.

Troubleshooting

MCP Inspector Connection Error

If you see a connection error in MCP Inspector asking for a proxy session token, make sure you start the Inspector with the server URL including your token, like this:

http://localhost:6274/?MCP_PROXY_AUTH_TOKEN=YOUR_TOKEN_HERE#resources

Example:

http://localhost:6274/?MCP_PROXY_AUTH_TOKEN=1f874aa0441c94cb870f4b4a14c3f5b76e5a814e422ba86687a98396b7fb5846#resources

Replace YOUR_TOKEN_HERE with your actual session token.