Simon WillisonSaturday · August 1, 2026FREE

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

Simon Willison writes that the rollout of the stateless MCP specification, dated 2026-07-28, has reignited his interest in the Model Context Protocol. He notes that the new stateless approach reduces the complexity of implementing both clients and servers, contrasting it with the older stateful MCP, which required two HTTP requests—one to initialize a session and obtain a session ID, and another to call a tool. The stateless version uses a single HTTP request with headers like MCP-Protocol-Version and Mcp-Method, eliminating the need for server-side session state. Willison built three projects this week: mcp-explorer, a stateless Python CLI tool for interactively probing MCP servers, which can be run via uvx and supports commands like list, inspect, and call; datasette-mcp, a Datasette plugin that adds a /-/mcp endpoint to any Datasette instance, providing three tools: list_databases(), get_database_schema(database_name), and execute_sql(database_name, sql), with execute_sql being read-only for the moment; and llm-mcp-client, an alpha plugin for his LLM tool that adds MCP integration. He also mentions running datasette-mcp on his blog's Datasette mirror and shares a TIL on attaching it to ChatGPT and Claude.