[BUG] File/folder menu with @ does not appear immediately—shows only after typing a character

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

When typing '@' in the Claude Code CLI to mention a file or folder, the autocomplete menu that should show files/folders in the working directory does not appear immediately. The menu only pops up after any character is typed following '@'. This makes it harder to quickly navigate or select files/folders, especially in directories with many items.

What Should Happen?

I expect the autocomplete menu to open immediately upon typing '@' and to list all files and folders available in the current working directory, without requiring an additional character to trigger it.

Error Messages/Logs

Steps to Reproduce

1. Start Claude Code from terminal (tested on Terminal.app, iTerm2, Warp).
2. In the prompt, type only the '@' character.
3. Observe that the autocomplete menu does not appear.
4. Type any character after '@' (e.g. '@a').
5. The autocomplete menu now shows files and folders.
6. This happens in any tested working directory.

Claude Model

Not sure / Multiple models

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.31 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

iTerm2

Additional Information

The bug is reproducible on several terminals (Terminal.app, iTerm2, Warp) and in multiple test directories. No error logs are shown: the menu simply does not appear until a further character is typed after '@'.