Stateless MCP has recaptured my interest (and inspired mcp-explorer and datasette-mcp)

<p>Tuesday was <a href="https://x.com/ade_oshineye/status/2082129440943866149">Stateless MCP day</a> - the rollout of MCP 2.0, or <a href="https://blog.modelcontextprotocol.io/posts/2026-07-28/">the 2026-07-28 Model Context Protocol specification</a> to use the more formal but less memorable name. This is the most significant change to the MCP spec since it first launched, and has also served to reignite my personal interest in the protocol.</p> <p>For background: MCP is the Model Context Protocol, which describes a standard way to expose new tools to LLM-powered agent frameworks. It was introduced by Anthropic back <a href="https://www.anthropic.com/news/model-context-protocol">in November 2024</a>, had a <em>huge</em> spike of interest through much of 2025, and then became somewhat eclipsed by <a href="https://simonwillison.net/2025/Oct/16/claude-skills/">Skills</a> (another Anthropic invention) when it became apparent that an agent harness with access to a terminal and <code>curl</code> could do most of what MCP did in a more flexible way. I wrote about that <a href="https://simonwillison.net/2025/Dec/31/the-year-in-llms/#the-only-year-of-mcp">in my review of 2025</a>.</p> <p>I'm coming back around to MCP now. Giving an agent a shell environment with the ability to access the internet is <a href="https://simonwillison.net/2026/Jul/22/openai-cyberattack/">fraught with risk</a>, and requires a strong model that is capable of effectively driving such an environment. MCP tools are easier to audit and control, and simple enough that smaller models that run on a laptop can still drive them reasonably well.</p> <p>The new stateless MCP specification also greatly decreases the complexity of implementing both clients and servers for the protocol. I built three of those this week!</p> <h4 id="what-s-easier-with-stateless-mcp">What's easier with stateless MCP</h4> <p>The best demonstration of the difference between stateful and stateless MCP is in this <a href="https://blog