Clojure-mcp fails when CIDER middleware is enabled (project directory detection fails)

[u473t8]

Description

I’m seeing a crash in clojure-mcp when connecting to an nREPL that was started with CIDER middleware enabled.

The MCP server throws ex-info "No project directory!!" and kills the REPL process.
The same setup works correctly if CIDER middleware is removed.

This looks like an incompatibility between clojure-mcp’s project directory detection and cider.nrepl/cider-middleware.

Version used:

v0.1.12

Reproduction Steps

1. deps.edn (project directory)

{:aliases
 {:nrepl
  {:extra-deps
   {nrepl/nrepl                   {:mvn/version "1.5.1"}
    cider/cider-nrepl             {:mvn/version "0.58.0"}
    refactor-nrepl/refactor-nrepl {:mvn/version "3.11.0"}}

   :main-opts
   ["-m"           "nrepl.cmdline"
    "--middleware" "[refactor-nrepl.middleware/wrap-refactor]"
    "--middleware" "[cider.nrepl/cider-middleware]" ;; the issue disappears when this middleware is commented out
    "--port"       "7888"]}}}

2. Start nREPL (this works by itself)

clojure -M:nrepl --port 7888

3. Start clojure-mcp

clojure -X:mcp

4. Result
The MCP server fails with:

ex-info: No project directory!!

and the REPL process is terminated.

Expected behavior

Clojure-mcp should correctly determine the project directory.

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