--- author: "Umesh Malik" canonical: "https://umesh-malik.com/topics/mcp" description: "Practical guides to the Model Context Protocol: how to build an MCP server, deploy it on Cloudflare Workers, and handle OAuth and write-tool permissions." title: "MCP Servers — Build, Deploy & Authenticate | Umesh Malik" tokens: 1780 generator: "scripts/generate-page-markdown.mjs" --- Topic Hub # MCP The Model Context Protocol turns a website from something agents scrape into something they can call. These articles cover building an MCP server, deploying it on Cloudflare Workers, OAuth scopes, and write-tool permissions — from a server that actually ships on this site. MCPJSON-RPCCloudflare WorkersOAuth ## Articles 9 [![OAuth consent screen with optional scope checkboxes that let users narrow agent permissions](https://umesh-malik.com/blog/optional-oauth-scopes-mcp-servers-cover.png) Web Engineering • Aug 23, 2026 ### Configure Optional OAuth Scopes for MCP Servers and Agents Configure optional OAuth scopes so users can narrow agent permissions at consent. The API call, the UX, and handling partial grants. 6 min read Read more →](https://umesh-malik.com/blog/optional-oauth-scopes-mcp-servers) [![The five sandbox tools a Gemini agent hook intercepts, against the two tool families it never sees](https://umesh-malik.com/blog/gemini-agent-hooks-fail-open-cover.png) AI Security • Aug 19, 2026 ### Gemini agent hooks fail open: how to block a tool call anyway Gemini agent hooks fail open on every error path, and never fire for MCP or function tools. The deny contract, the coverage gap, and what to gate instead. 9 min read Read more →](https://umesh-malik.com/blog/gemini-agent-hooks-fail-open) [![The four agentic web layers — readable, discoverable, callable, payable — mapped to concrete URLs on a static site](https://umesh-malik.com/blog/make-your-site-agent-readable-cover.png) Web Engineering • Aug 7, 2026 ### How to Make Your Site Agent-Readable: 4 Layers, One Worker Make your site agent-readable in four layers — readable, discoverable, callable, payable. Three are build-time files; only /mcp needs a Worker. 10 min read Read more →](https://umesh-malik.com/blog/make-your-site-agent-readable) [![The browsing loop a code-review agent enters under generic tool instructions, versus the diff-anchored evidence path review-shaped instructions produce](https://umesh-malik.com/blog/writing-agent-tool-instructions-cover.png) AI Coding Agents & DX • Aug 7, 2026 ### Fix your agent tool instructions: GitHub's 20% review-cost cut Agent tool instructions decide what your agent costs. GitHub kept the same grep/glob/view toolset, rewrote the guidance, and cut review cost by ~20%. 9 min read Read more →](https://umesh-malik.com/blog/writing-agent-tool-instructions) [![MCP write controls diagram: a tool call passing through a policy layer that allows, labels, or blocks it before the handler runs](https://umesh-malik.com/blog/mcp-write-controls-cloudflare-writeguard-cover.png) AI Security • Aug 5, 2026 ### MCP Write Controls: Lessons from Cloudflare WriteGuard MCP write controls decide what your agents can break. Cloudflare's WriteGuard shows the pattern: per-tool risk tiers, agent attribution, central audit. 13 min read Read more →](https://umesh-malik.com/blog/mcp-write-controls-cloudflare-writeguard) [![Cover card titled The Gate, subtitled Thousands of tickets. One agent., with three statistics: 4 risk tiers, Cloudflare's MCP portal growing 13 to 27 servers, and tool annotations marked untrusted per the MCP spec](https://umesh-malik.com/blog/secure-mcp-write-tools-writeguard-cover.png) AI Security • Aug 5, 2026 ### How to Secure MCP Write Tools: Cloudflare's WriteGuard Lesson How to secure MCP write tools: the spec puts confirmation on the client — the one layer you don't control. Cloudflare's WriteGuard moves the gate server-side. 11 min read Read more →](https://umesh-malik.com/blog/secure-mcp-write-tools-writeguard) [![ChatGPT super app reform showing the Apps SDK built on MCP with inline app UIs and the App Directory](https://umesh-malik.com/blog/chatgpt-apps-sdk-cover.png) AI Engineering • Jul 11, 2026 ### ChatGPT Apps SDK and the Super App Reform: How Apps in ChatGPT Work (2026) The ChatGPT Apps SDK explained: how apps in ChatGPT work, why it's built on MCP, who the launch partners are, and how developers build and submit apps. 7 min read Read more →](https://umesh-malik.com/blog/chatgpt-apps-sdk-super-app-guide) [![Deploying a Model Context Protocol server to the edge on Cloudflare Workers](https://umesh-malik.com/blog/deploy-mcp-server-cloudflare-workers-cover.png) AI Engineering • Jun 8, 2026 ### Deploy an MCP Server on Cloudflare Workers (Free, at the Edge) Deploy an MCP server on Cloudflare Workers: wrangler.toml, the run\_worker\_first model, routing /mcp, local testing, and going live on the free tier. 7 min read Read more →](https://umesh-malik.com/blog/deploy-mcp-server-cloudflare-workers) [![Architecture of a production Model Context Protocol server on Cloudflare Workers](https://umesh-malik.com/blog/how-to-build-mcp-server-cover.png) AI Engineering • Jun 8, 2026 ### How to Build an MCP Server: A Step-by-Step Guide (2026) How to build an MCP server, step by step: JSON-RPC 2.0, the Streamable HTTP transport, typed tools, and agent discovery — from a real one I shipped. 9 min read Read more →](https://umesh-malik.com/blog/how-to-build-mcp-server) ## Frequently Asked Questions ### What is the Model Context Protocol (MCP)? MCP is an open protocol that lets AI agents call typed tools over JSON-RPC instead of scraping web pages. A server exposes tools/list and tools/call; a client (Claude, Cursor, ChatGPT) discovers those tools and invokes them. The usual transport is Streamable HTTP — one POST /mcp endpoint. ### How do I build an MCP server? You need four JSON-RPC methods: initialize, tools/list, tools/call, and ping. A stateless Cloudflare Worker that returns plain JSON is fully spec-compliant. Back the tools with data you already publish (a JSON feed, Markdown pages) so there is one source of truth. Full walkthrough: https://umesh-malik.com/blog/how-to-build-mcp-server. ### Do MCP servers need authentication? Public read-only tools can stay anonymous. Write tools and private data need OAuth (or a similar token). Optional OAuth scopes let the user narrow permissions at consent time so an agent does not get a broader grant than the task needs. ### Where should I host an MCP server? Anywhere that can serve HTTPS JSON. Cloudflare Workers is a common fit: one file, a free tier, and you can pin the Worker to /mcp so the rest of a static site stays on the asset worker. Guide: https://umesh-malik.com/blog/deploy-mcp-server-cloudflare-workers. Google Search · Preferred sources ## Prefer this site on Google If you already read this writing, add umesh-malik.com as a Preferred Source. Google can then highlight it with a preferred badge in Top Stories, AI Overviews, and AI Mode — for you, not as a site-wide ranking boost. [Open in Google Search(opens Google Preferred Sources in a new tab)](https://www.google.com/preferences/source?q=umesh-malik.com) ## Related Topics [Claude Code →](https://umesh-malik.com/topics/claude-code)[LLM Engineering →](https://umesh-malik.com/topics/llm-engineering)[AI Coding Agents →](https://umesh-malik.com/topics/ai-coding-agents) [All Articles →](https://umesh-malik.com/blog)