I've pushed the extension to GitHub at https://github.com/Warbo/pi-extensions/tree/master/extension...
The implementation is pretty terrible: a giant string of vibe-coded Emacs Lisp is sent to emacsclient, which performs the actions and sends back a string of JSON.
It's been interesting to iterate on the approach: watching the LLM (in my case Claude) attempting to use the tools; noticing when it struggles or makes incorrect assumptions; and updating the tool, documentation and defaults to better match those expectations.
I've also written some Emacs Lisp which opens Pi and tells it to "Action the request/issue/problem at point in buffer '<current-buffer>'" https://github.com/Warbo/warbo-emacs-d/blob/a13a1e02f5203476...
It feels similar to the file-watching provided by Aider (which uses inotify to spot files containing `# AI!` or `# AI?`), which I've previously used with FIXME and TODO comments in code; but it also works well in non-file things, e.g. error messages and test failures in `shell-mode`, and issues listed in the Emacs UI I wrote for the Artemis bug tracker (Claude just gets the issue number from the current line, and plugs that into a Pi extension I made for Artemis :-) )
Oh that sounds neat. I'll need to check out your extension!