MCP Extension for SillyTavern

This extension adds WebSocket-based tool execution support to SillyTavern, allowing external tools to be registered and executed through a standardized interface.

Features

WebSocket server for real-time communication
Tool registration and execution system
JSON Schema validation for tool definitions
Real-time execution status updates
Configurable logging and WebSocket settings
Web-based settings UI integrated into SillyTavern

Installation

Method 1: Web Interface (Recommended)

See INSTRUCTIONS.md for step-by-step instructions on installing through SillyTavern's web interface.

Method 2: Manual Installation

Clone this repository into your SillyTavern plugins directory:
cd /path/to/SillyTavern/plugins git clone https://github.com/CG-Labs/SillyTavern-MCP-Extension.git mcp-extension
Install dependencies:
cd mcp-extension npm install
Restart SillyTavern

Configuration

The extension can be configured through the SillyTavern UI under Settings > Extensions > MCP Extension.

Available Settings

WebSocket Port: The port number for the WebSocket server (default: 5005)
Log Level: Logging verbosity level (debug, info, warn, error)

Usage

Registering a Tool

To register a tool, send a WebSocket message with the following format:

{
    "type": "register_tool",
    "data": {
        "name": "example_tool",
        "schema": {
            "type": "object",
            "properties": {
                "param1": {
                    "type": "string",
                    "description": "First parameter"
                },
                "param2": {
                    "type": "number",
                    "description": "Second parameter"
                }
            },
            "required": ["param1"]
        }
    }
}

Executing a Tool

To execute a registered tool, send a WebSocket message with the following format:

{
    "type": "execute_tool",
    "data": {
        "executionId": "unique_execution_id",
        "name": "example_tool",
        "args": {
            "param1": "value1",
            "param2": 42
        }
    }
}

Execution Status Updates

The extension broadcasts execution status updates to all connected clients:

Execution Started

{
    "type": "tool_execution_started",
    "data": {
        "executionId": "unique_execution_id",
        "name": "example_tool",
        "args": {
            "param1": "value1",
            "param2": 42
        }
    }
}

Execution Completed

{
    "type": "tool_execution_completed",
    "data": {
        "executionId": "unique_execution_id",
        "result": {
            // Tool-specific result data
        }
    }
}

Execution Failed

{
    "type": "tool_execution_failed",
    "data": {
        "executionId": "unique_execution_id",
        "error": {
            "code": "ERROR_CODE",
            "message": "Error message"
        }
    }
}

Error Codes

INVALID_NAME: Invalid tool name
INVALID_SCHEMA: Invalid tool schema
INVALID_URI: Invalid resource URI
INVALID_HANDLER: Invalid handler implementation
INVALID_ARGUMENTS: Invalid tool arguments
TOOL_EXISTS: Tool already registered
TOOL_NOT_FOUND: Tool not found
TOOL_EXECUTION_FAILED: Tool execution failed
SERVER_ERROR: Internal server error

Development

Project Structure

mcp-extension/
├── index.js              # Main plugin entry point
├── manifest.json         # Plugin manifest
├── package.json         # Dependencies and scripts
├── public/              # Public assets
│   ├── script.js        # Client-side JavaScript
│   ├── style.css        # Client-side styles
│   └── templates/       # HTML templates
├── utils/               # Utility modules
│   ├── errors.js        # Error handling
│   ├── logger.js        # Logging utility
│   └── validation.js    # Input validation
└── README.md            # This documentation

Adding New Tools

To add a new tool:

Connect to the WebSocket server
Register your tool with a schema
Listen for execution requests
Handle execution and return results

Example tool implementation:

const ws = new WebSocket('ws://localhost:5005');

ws.onopen = () => {
    // Register tool
    ws.send(JSON.stringify({
        type: 'register_tool',
        data: {
            name: 'example_tool',
            schema: {
                type: 'object',
                properties: {
                    input: {
                        type: 'string'
                    }
                },
                required: ['input']
            }
        }
    }));
};

ws.onmessage = (event) => {
    const message = JSON.parse(event.data);
    
    if (message.type === 'execute_tool' && 
        message.data.name === 'example_tool') {
        // Handle execution
        const result = doSomething(message.data.args.input);
        
        // Send result
        ws.send(JSON.stringify({
            type: 'tool_execution_completed',
            data: {
                executionId: message.data.executionId,
                result
            }
        }));
    }
};

Contributing

Fork the repository
Create a feature branch
Commit your changes
Push to the branch
Create a Pull Request

Support

If you encounter any issues or have questions:

Check the GitHub Issues for existing problems
Create a new issue if your problem hasn't been reported
Join the SillyTavern Discord community for support

License

MIT License - see LICENSE file for details

SillyTavern MCP Server