# Simon Willison — Stateless MCP spawns mcp-explorer and datasette-mcp

> Simon Willison argues MCP 2.0's stateless transport is the biggest spec change since launch, and ships two demos to prove it.

- Org: Simon Willison
- Date: 2026-07-31
- Category: article
- Source: https://simonwillison.net/2026/Jul/31/stateless-mcp/
- Canonical page: https://ai-tldr.dev/releases/simonw-stateless-mcp-jul31/

## In short

Simon Willison walks through MCP 2.0's stateless transport, calls it the biggest change since the protocol shipped, and open-sources two new demos — mcp-explorer for probing servers and datasette-mcp for exposing SQLite over the new spec.

## What it is

Simon Willison's July 31 post is a roughly 2,100-word walkthrough of the Model Context Protocol 2026-07-28 revision — 'MCP 2.0' — plus two open-source companion projects he built while playing with the new transport: mcp-explorer, a probe for MCP servers, and datasette-mcp, an adapter that exposes any Datasette instance over MCP.

## How it works

The new spec drops the long-lived HTTP+SSE session model in favor of stateless calls that each carry their own context — closer to a normal HTTP API than the earlier connect-and-hold design. Willison uses that shift to build mcp-explorer as a plain client that can be pointed at any server and inspect its tools, and datasette-mcp as a wrapper that turns Datasette's read-only query API into an MCP-compliant surface consumable by Claude, LLM CLI, and other MCP clients.

## Why it matters

MCP has been notoriously hard to reason about because of its long-lived state; the stateless variant means an MCP server can now be a normal HTTP handler you deploy anywhere, which is what MCP needed to make the leap from Anthropic's ecosystem to general infrastructure. When someone with Willison's profile ships both a well-argued explainer and two working tools on the same day, it materially accelerates how many people can pick the protocol up.

## Who it's for

Developers evaluating MCP for their own products or trying to expose an existing data source to Claude and other MCP clients.

## Try it

pip install mcp-explorer  # then point it at any MCP 2.0 endpoint

## Links

- [Article](https://simonwillison.net/2026/Jul/31/stateless-mcp/)
- [mcp-explorer](https://github.com/simonw/mcp-explorer)
- [datasette-mcp](https://github.com/datasette/datasette-mcp)
- [MCP 2026-07-28 spec](https://modelcontextprotocol.io/specification/2026-07-28)