Stateless MCP has recaptured my interest

(simonwillison.net)

19 points | by tosh 3 days ago

5 comments

  • CharlieDigital 16 minutes ago
    Stateless MCP was already possible before this and made sense for whole classes of use cases where it helps to have a remote fleet of servers.

    Wrote about this back in March: https://chrlschn.dev/blog/2026/03/mcp-is-dead-long-live-mcp/

    MCP is going to be a foundational piece of enterprise agent infra.

  • pianopatrick 28 minutes ago
    Maybe someone could set up a CLI tool for agents such that you can give them a shell but they use this CLI tool instead of raw curl.

    Like a tool where the AI can only call out to certain APIs based on a config file the agent cannot change.

    That way you can leverage all the shell knowledge agents already have while still limiting what network calls they can make, and you wouldn't have to set up a server to use an agent.

    • nickstinemates 2 minutes ago
      This is basically what Swamp is[1]. You give an agent a typed interface to extend itself (or use other peoples extensions) into the systems you need to fulfill your request. Think of it like on-demand tool calls. Then it records everything that happens in the swamp. The swamp can be single machine, multi-machine, or centralized with your co-workers.

      As a result, everything compounds. The work I do doesn't need to be re-derived by the work you do. Typed models keep everything repeatable and deterministic. Huge reduction in token spend and huge increase in speed.

      1: https://swamp-club.com

    • Wuzzy 7 minutes ago
      I think this exists: https://github.com/imbue-ai/latchkey (and there are other similar projects, too).
    • parf02 24 minutes ago
      A proxy?
      • pianopatrick 18 minutes ago
        Maybe. I'm just spitballing but as I've been thinking about this, maybe just like a set of shell scripts.

        The idea could be that the agent runs as a unix user. That user has execute access to these scripts but not read or write access.

        So the agent can only do what those scripts allow, the scripts present an API. You could let agents call the scripts with -h to get instructions, and just put some text into context saying like "to access helper scripts call ./showHelp".

  • ameshkov 56 minutes ago
    > I couldn’t find a great CLI tool for interactively probing an MCP server

    What about mcp-inspector? It’s a nice tool, can be used interactively, can be used as a CLI.

    https://github.com/modelcontextprotocol/inspector

  • tosh 34 minutes ago
    I'm glad MCP is getting simpler

    a few months ago I tried to implement an MCP server from scratch in python (instead of using the existing reference implementation) and I could not get it to work reliably across clients

  • brianjking 3 days ago
    Yeah, there's a ton of great improvements in 7-28. I'm personally excited about what you posted about, but also with [tasks](https://blog.modelcontextprotocol.io/posts/2026-07-28-releas...) being officially adopted.