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-extensionInstall dependencies:
cd mcp-extension npm installRestart 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 nameINVALID_SCHEMA: Invalid tool schemaINVALID_URI: Invalid resource URIINVALID_HANDLER: Invalid handler implementationINVALID_ARGUMENTS: Invalid tool argumentsTOOL_EXISTS: Tool already registeredTOOL_NOT_FOUND: Tool not foundTOOL_EXECUTION_FAILED: Tool execution failedSERVER_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
Project Details
- CG-Labs/SillyTavern-MCP-Extension
- Last Updated: 4/21/2025
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