Time MCP Server

# CLAUDE.md This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository. ## Project Overview This is a Cloudflare Workers-based MCP (Model Context Protocol) server that provides timezone-aware time information. The project uses the `@modelcontextprotocol/sdk` to implement an MCP server and the `agents` package to create HTTP handlers for Cloudflare Workers. ## Development Commands ### Run Development Server ```bash npm run dev ``` Starts the Wrangler development server with hot-reload. The server will be available locally. ### Deploy to Cloudflare ```bash npm run deploy ``` Deploys the Worker to Cloudflare's edge network. ### Deploy with Custom Timezone ```bash wrangler deploy --var DEFAULT_TIMEZONE:America/New_York ``` Override the default timezone (defaults to `Asia/Tokyo`) during deployment. ## Architecture ### Core Components **src/index.ts** - Main entry point containing: - MCP server initialization with `@modelcontextprotocol/sdk` - Single tool: `get_time` - returns current time in specified IANA timezone - Cloudflare Workers fetch handler that processes MCP requests via HTTP - Environment variable handling for timezone configuration ### Key Technical Details **Timezone Handling**: Uses `Intl.DateTimeFormat` to format times in any IANA timezone. The `formatTime()` function: - Formats date/time components using the specified timezone - Calculates UTC offset by comparing UTC and zoned timestamps - Returns ISO 8601-like format: `YYYY-MM-DDTHH:MM:SS±HH:MM` **Environment Variables**: - `DEFAULT_TIMEZONE` is configured in `wrangler.toml` and accessed via Cloudflare Workers `env` object - Stored in module-scoped `currentEnv` variable to be accessible in MCP tool handlers **MCP Integration**: - Uses `createMcpHandler` from `agents/mcp` to bridge MCP server and Cloudflare Workers - CORS is enabled with `allowOrigin: '*'` for broad client access - Tool schema validation uses Zod ### Configuration Files - **wrangler.toml**: Cloudflare Workers configuration including compatibility settings and environment variables - **tsconfig.json**: TypeScript config targeting ES2021 with WebWorker libraries for Cloudflare Workers environment - **package.json**: Dependencies include MCP SDK, agents framework for Workers integration, and Zod for validation ## Important Notes - This project uses ES modules (`"type": "module"`) - The Workers runtime requires `nodejs_compat` compatibility flag - Timezone parameter is optional; falls back to env `DEFAULT_TIMEZONE` then `Asia/Tokyo` - The MCP server exposes a single tool that can be called by any MCP client