Consider removing the shadow-cljs warning in every REPL invocation?

[jwr]

It seems every time an agent connects to an nREPL, and the project uses shadow-cljs, these messages are printed:

 ;; shadow-cljs repl is NOT in CLJS mode
 ;; use (shadow/active-builds) to list builds available
 ;; use (shadow/repl <build-id>) to jack into a CLJS repl

Apart from eating tokens, these sometimes confuse Claude Code into thinking the REPL isn't working correctly and it starts to use lsof to search for nrepl ports…

I think placing instructions about shadow-cljs in a CLAUDE.md or AGENTS.md file would be a more general solution, and perhaps these could be removed?

Also, thank you for all the work on clojure-mcp, it works really well and helps immensely! 🙏

[bhauman]

This seems wasteful but having seen the behavior when these messages are not there, this is what I arrived at. Claude was always confused as to what the given state of the REPL was and was always executing things on the wrong side and not understanding why things didn't work. Which in turn lead to lots and lots of wasted effort.

The other problem with requiring custom instructions is that many folks won't do it and then the repl simply wont work for them.

I think the instructions could be less verbose but I genuinely see way less misunderstandings and bad behavior with this help included in the shadow repl.

That being said this could be configurable on the command line.

[theronic]

If this is via clj-nrepl-eval, would two separate calls, cljs-nrepl-eval vs clj-nrepl-eval help the model to distinguish implicitly?

[jwr]

My experience is exactly the opposite: Claude Code gets confused by these instructions. What I did to work around the problem was fork clojure-mcp, remove these messages, and instead create instructions in CLAUDE.md. Since then I had no confusion and Claude was able to use the REPL predictably.

This is what I added to CLAUDE.md:

The app uses shadow-cljs and the nREPL connection can be used to either connect to a Clojure REPL (server-side, default), or to a ClojureScript browser REPL for testing ClojureScript code. To use the ClojureScript REPL, use (shadow/active-builds) to list builds available, then use (shadow/repl <build-id>) to jack into a ClojureScript REPL.