Holster

Holster

A Python-based tool for managing MCP servers in Claude's configuration file directly from Claude desktop, eliminating the need for manual text editor modifications.

Motivation

Although Claude is prompted not to use tools when not necessary, it is often too eager to invoke tools at its disposal. But who's gonna add and remove MCP servers manually?

Managing MCP servers through text editors is a task well-suited for LLMs, but Claude currently only provides a pointer to the config file. Holster aims to improve this experience by providing a seamless interface for server management directly within Claude desktop.

Features

• 🔄 Seamless server management within Claude desktop
• 📝 JSON configuration handling with proper parsing and encoding
• 📋 Separate tracking of active and inactive servers
• 🛠️ Simple command-line interface
• ✅ Comprehensive test coverage

Installation

1. Clone the repository:

git clone https://github.com/yourusername/holster.git
cd holster

2. Create and activate a virtual environment:

python -m venv .venv
source .venv/bin/activate  # On Windows: .venv\Scripts\activate

3. Install dependencies using uv:

uv pip install -r requirements.txt

Configuration

The default configuration file location is:

~/Library/Application Support/Claude/claude_desktop_config.json

Add this to your growing list of MCP servers:

    "holster": {
        "command": "uv",
        "args": [
            "--directory",
            "<THIS_DIRECTORY>",
            "run",
            "holster.py"
        ]
    }

Restart Claude to reload the config.

Usage

Understanding Holster

First, you can get a comprehensive explanation of how Holster works:

# Get detailed explanation of Holster's functionality
explanation = await explain_holster()
print(explanation["overview"])
print(explanation["tools"])

Creating a New Server

# Create a new server configuration
server_config = await create_server(
    name="my_server",
    command="uv",
    directory="/path/to/server",
    script="server.py"
)

Reading Server Status

# Get lists of active and inactive servers
servers = await list_servers()
print("Active servers:", list(servers["active"].keys()))
print("Inactive servers:", list(servers["inactive"].keys()))

Updating Server Status

# Deactivate servers
result = await update_server_status(
    server_names=["server1", "server2"],
    active=False
)
print(f"Deactivated {len(result['updated'])} servers")

# Activate servers
result = await update_server_status(
    server_names=["server1", "server2"],
    active=True
)
print(f"Activated {len(result['updated'])} servers")

Deleting Servers

# Delete servers from both active and inactive lists
result = await delete_servers(["server1", "server2"])
print(f"Deleted {len(result['deleted'])} servers")
print(f"Remaining active: {result['remaining_active']}")
print(f"Remaining inactive: {result['remaining_inactive']}")

Health Check

# Check if Holster server is running
response = await ping()
print(response)  # Should print "Pong!"

Development

Running Tests

python -m pytest test_holster.py -v

Scope

In Scope

• Server configuration management within Claude's config file
• Tracking of active and inactive servers
• Basic CRUD operations for server configurations

Out of Scope

• Automatic server discovery and downloading
• Web-based server search
• Workspace management
• Server versioning

License

This project is licensed under the MIT License - see the LICENSE file for details.

Author

June Kim & LLM tools