Xava Labs Typescript MCP Template

A template repository for bootstrapping MCPs (Model Context Protocol) for the xava-labs/typescript-agent-framework.

Getting Started

Setup the repository

Option A: Use this template*

1. Click the "Use this template" button at the top of this repository
2. Clone your new repository

Option b: Use wrangler init

You can create a new project based on this template using wrangler:

npx wrangler init my-mcp-project --git https://github.com/xava-labs/mcp-template
cd my-mcp-project

Once you have completed one of the above methods, then run the following commands in your terminal to get started:

yarn install
yarn dev

The above will boostrap a serverless cloudflare compatible MCP Server with the following urls:

• /ws - Websocket connection endpoint
• /sse - SSE connection endpoint

Features

• WebSocket Client Support: Includes official WebSocket client for real-time bidirectional communication
• SSE Client Support: Includes Server-Sent Events client for server-to-client streaming
• MCP Inspector: Debug and monitor your MCP during development
• Cloudflare Workers Integration: Built on Cloudflare Workers for edge computing capabilities
• Integration Testing Suite: Websocket and SSE testing tools to do full integration testing with local miniflare services (D1/KV/etc) for ease of testing features without mocking.

Available Scripts

• yarn dev: Runs both the MCP Inspector (port 6274) and Cloudflare Worker (port 8787) concurrently
• yarn start: Runs only the Cloudflare Worker (port 8787)
• yarn test: Runs tests with Vitest
• yarn deploy: Deploys your MCP to Cloudflare Workers
• yarn cf-typegen: Generates TypeScript types for Cloudflare Workers (run this everytime you add new changes to wrangler.jsonc)

Development

This template implements an MCP server using Durable Objects for stateful connections. The base project structure offers two main approaches for extending functionality:

McpHonoServerDO Implementation

By default, the template uses McpHonoServerDO which combines the MCP server with Hono, a fast and lightweight web framework. This provides a clean routing system and middleware capabilities.

Extending with Tools, Resources, and Prompts

The main server implementation is in src/server.ts and extends McpHonoServerDO:

export class ExampleMcpServer extends McpHonoServerDO {
  // Required abstract method implementation
  getImplementation(): Implementation {
    return {
      name: 'ExampleMcpServer',
      version: '1.0.0',
    };
  }

  // Configure server by adding tools, resources, and prompts
  configureServer(server: McpServer): void {
    setupServerTools(server);
    setupServerResources(server);
    setupServerPrompts(server);
  }
}

To add functionality, use the following modules:

1. Tools (src/tools.ts): Define functions that clients can call

export function setupServerTools(server: McpServer) {
  server.tool(
    'tool_name',           // Name of the tool
    'Tool description',    // Description
    {                      // Parameters schema using zod
      param1: z.string().describe('Parameter description'),
    },       
    async ({ param1 }) => {
      // Tool implementation
      return {
        content: [
          {
            type: "text",
            text: `Result: ${param1}`
          }
        ]
      };
    }
  );
}

2. Resources (src/resources.ts): Define persistent resources clients can access

export function setupServerResources(server: McpServer) {
  server.resource(
    'resource_name',
    'resource://path/{id}',
    async (uri: URL) => {
      // Resource implementation
      return {
        contents: [
          {
            text: `Resource data`,
            uri: uri.href
          }
        ]
      };
    }
  );
}

3. Prompts (src/prompts.ts): Define prompt templates

export function setupServerPrompts(server: McpServer) {
  server.prompt(
    'prompt_name',
    'Prompt description',
    () => ({
      messages: [{
        role: 'assistant',
        content: {
          type: 'text',
          text: `Your prompt text here`
        }
      }]
    })
  );
}

Customizing Routes with Hono

To add custom HTTP endpoints with McpHonoServerDO, extend the setupRoutes method:

export class ExampleMcpServer extends McpHonoServerDO {
  // Other methods...

  protected setupRoutes(app: Hono): void {
    // Call the parent implementation to set up MCP routes
    super.setupRoutes(app);
    
    // Add your custom routes
    app.get('/api/status', (c) => {
      return c.json({ status: 'ok' });
    });
    
    app.post('/api/data', async (c) => {
      const body = await c.req.json();
      // Process data
      return c.json({ success: true });
    });
  }
}

McpServerDO Implementation (Native Cloudflare Routing)

If you need more control over the HTTP request handling, you can directly extend McpServerDO instead. This gives you full control over the fetch method:

export class CustomMcpServer extends McpServerDO {
  // Required abstract method implementations
  getImplementation(): Implementation {
    return {
      name: 'CustomMcpServer',
      version: '1.0.0',
    };
  }
  
  configureServer(server: McpServer): void {
    setupServerTools(server);
    setupServerResources(server);
    setupServerPrompts(server);
  }
  
  // Override the fetch method for complete control over routing
  async fetch(request: Request): Promise {
    const url = new URL(request.url);
    const path = url.pathname;
    
    // Handle custom routes
    if (path === '/api/custom') {
      return new Response(JSON.stringify({ custom: true }), {
        headers: { 'Content-Type': 'application/json' }
      });
    }
    
    // Pass through MCP-related requests to the parent implementation
    return super.fetch(request);
  }
}

This approach is useful when you need to:

• Handle specific routes with custom logic
• Implement complex middleware or authentication
• Intercept or modify requests before they reach the MCP handler
• Add custom WebSocket or SSE endpoints beyond the standard MCP implementation

Examples

CRUD Todo List Example

For a complete working example, check out the CRUD Todo List MCP Example which demonstrates:

• Full CRUD operations using MCP tools
• SQLite database integration for persistence
• Real-time updates via WebSocket/SSE
• Comprehensive error handling
• Advanced filtering and sorting capabilities
• Rich prompts and resources

Related Resources

Core Packages

• MCP Package: The core MCP implementation with advanced features and testing utilities
• TypeScript Agent Framework: Build intelligent agents powered by LLMs with the Agent Framework

Documentation

• Documentation: Coming soon!

Community

Join our community to get help, share ideas, and contribute to the project:

• Discord: Join the #mcp channel for feature requests, support, and discussions

Contributing

We welcome contributions to improve this template! Here's how you can contribute:

1. Fork the repository: Create a fork to make your changes

2. Create a branch: Make your changes in a new branch

   git checkout -b feature/your-feature-name

3. Commit your changes: Make meaningful commits

   git commit -m "Add feature: brief description"

4. Push to your fork: Push your changes to your fork

   git push origin feature/your-feature-name

5. Create a pull request: Open a PR with a detailed description of your changes

Pull Request Guidelines

• Provide a clear, descriptive title for your PR
• Include a detailed description of what your PR does
• Reference any related issues
• Include screenshots or examples if applicable
• Ensure all tests pass
• Keep PRs focused on a single feature or fix

For larger changes or features, we recommend discussing them first in our Discord channel to ensure alignment with the project direction.

Deployment

To deploy your MCP to Cloudflare Workers, run:

yarn deploy

Or use the Deploy to Cloudflare button above to deploy directly from GitHub.

License

MIT