Simple MPC Server on Deno (Windows)

claude_desktop_config.json

{
  "mcpServers": {
    "mzdev": {
      "command": "path\\to\\deno.exe",
      "args": ["run", "-A", "path\\to\\main.ts"]
    }
  }
}

main.ts

#!/usr/bin/env -S deno run --watch --allow-net --allow-env --allow-run --allow-sys --allow-read --allow-write

// Simple implementation on deno server
import { Server } from "npm:@modelcontextprotocol/sdk/server/index.js";
import { StdioServerTransport } from "npm:@modelcontextprotocol/sdk/server/stdio.js";
import {
  CallToolRequestSchema,
  ListResourcesRequestSchema,
  ListToolsRequestSchema,
  CallToolResult,
  Tool,
  CallToolRequest,
} from "npm:@modelcontextprotocol/sdk/types.js";

const TOOLS: Tool[] = [
  {
    name: "getStringLength",
    description: "Get the length of a string",
    inputSchema: {
      type: "object",
      properties: {
        input: { type: "string" },
      },
      required: ["input"],
    },
  },
];

async function handleToolCall(
  name: string,
  args: Record<string, unknown>
): Promise<{ toolResult: CallToolResult }> {
  switch (name) {
    case "getStringLength": {
      const input = args.input as string;
      if (typeof input !== "string") {
        return {
          toolResult: {
            content: [
              {
                type: "text",
                text: `Expected input to be a string, got ${typeof input}`,
              },
            ],
            isError: true,
          },
        };
      } else {
        return {
          toolResult: {
            content: [
              {
                type: "text",
                text: `${Array.from(input).length}`,
              },
            ],
            isError: false,
          },
        };
      }
    }
    default: {
      return {
        toolResult: {
          content: [
            {
              type: "text",
              text: `Unknown tool: ${name}`,
            },
          ],
          isError: true,
        },
      };
    }
  }
}

const server = new Server(
  {
    name: "mzdev",
    version: "0.1.0",
  },
  {
    capabilities: {
      resources: {},
      tools: {},
    },
  }
);

server.setRequestHandler(ListResourcesRequestSchema, () => ({
  resources: [],
  // resources: [
  //   {
  //     uri: "console://logs",
  //     mimeType: "text/plain",
  //     name: "Browser console logs",
  //   },
  // ],
}));

server.setRequestHandler(ListToolsRequestSchema, () => ({ tools: TOOLS }));
server.setRequestHandler(CallToolRequestSchema, (request: CallToolRequest) =>
  handleToolCall(request.params.name, request.params.arguments ?? {})
);

const transport = new StdioServerTransport();
await server.connect(transport);
console.error("MCP server running on stdio");