diff --git a/src/Roux/Server.hs b/src/Roux/Server.hs
index 05e74ba..4a61fd5 100644
--- a/src/Roux/Server.hs
+++ b/src/Roux/Server.hs
@@ -479,7 +479,11 @@ findConvertScript = do
     mPath <- findExecutable "convert-to-cooklang"
     case mPath of
         Just p -> pure p
-        Nothing -> makeAbsolute "scripts/convert-to-cooklang"
+        Nothing ->
+            ioError $
+                userError $
+                    "convert-to-cooklang not found on PATH. "
+                        <> "Install it to /usr/local/bin/convert-to-cooklang or add it to PATH."
 
 -- | Write a temporary YAML config for the subprocess.
 writeConvertConfig :: FilePath -> AnthropicConfig -> IO ()