Deno MCP Server

The Deno Model Context Protocol (MCP) server provides a bridge for AI assistants, like Cursor, to interact with your Deno projects. It enables functionalities such as running tests and viewing code coverage directly within your development environment.

Features

• Run Deno Tests: Execute tests for specific files, directories, or your entire project.
  • Supports standard Deno test options:
    • --coverage: Collect coverage profile data.
    • --doc: Evaluate code blocks in JSDoc and Markdown.
    • --update: Update snapshot files for test cases.
    • --trace-leaks: Enable tracing of resource leaks.
• View Code Coverage: Display detailed coverage reports generated by deno coverage.

Getting Started

To integrate the Deno MCP server with Cursor, add the following configuration to your workspace's .cursor/mcp.json file:

{
  "mcpServers": {
    "deno": {
      "command": "deno",
      "args": ["run", "-A", "jsr:@udibo/deno-mcp", "-A"]
    }
  }
}

After adding this configuration, restart the MCP tool in your Cursor settings to apply the changes.

Important Note on Arguments: Any arguments provided in the args array after the script path (e.g., jsr:@udibo/deno-mcp or ./custom-server.ts) will be automatically passed to the deno test command when the test tool is executed. For instance, the trailing -A in the example configurations above will be included in all test tool invocations, effectively running tests with all permissions by default.

Example Usage

Here's an example of Cursor interacting with the Deno MCP server to run tests:

Extending the Server

You can extend the base Deno MCP server with your own custom tools. This allows you to tailor its functionality to your specific project needs.

Example: Adding an echo tool

1. Create a new TypeScript file (e.g., custom-server.ts):

   import { server, StdioServerTransport } from "jsr:@udibo/deno-mcp"; // Or your local path if developing
   import { z } from "https://deno.land/x/zod@v3.22.4/mod.ts"; // Or your preferred way to import Zod
   
   server.tool(
     "echo",
     {
       message: z.string().describe("The message to echo."),
     },
     {
       "title": "Echo Message",
       "description": "A simple tool that echoes back the provided message.",
     },
     ({ message }) => {
       return Promise.resolve({
         content: [{
           type: "text",
           text: `Echo: ${message}`,
         }],
       });
     },
   );
   
   if (import.meta.main) {
     const transport = new StdioServerTransport();
     await server.connect(transport);
   }

2. Update your .cursor/mcp.json to use your custom server script:

   {
     "mcpServers": {
       "deno": {
         "command": "deno",
         "args": ["run", "-A", "./custom-server.ts", "-A"]
       }
     }
   }

3. Important: Restart the MCP tool in your Cursor settings for the changes to take effect. Remember the note above about arguments: the trailing -A here will also be passed to deno test.

Contributing

Contributions are welcome! Please feel free to open an issue or submit a pull request.

License

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