[BUG] "@" symbol can crash claude code

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 using the @ symbol to find files, it can often cause claude code to hang as it's obviously trying to index all files.

What Should Happen?

using the @ symbol should trigger a background task to index files in the folder we're in and show progress of this, if the file list is very large.

Error Messages/Logs

n/a

Steps to Reproduce

1. Use this script to generate a sufficiently large list of files
2. run claude code
3. Type @ and watch in terror as the whole terminal crashes!

#!/bin/bash

# Script to generate 20,000 files with random names
# Creates files in a 'random_files' directory

TOTAL_FILES=20000
OUTPUT_DIR="random_files"

# Create output directory if it doesn't exist
mkdir -p "$OUTPUT_DIR"

echo "Generating $TOTAL_FILES files with random names in $OUTPUT_DIR/"

for ((i=1; i<=TOTAL_FILES; i++)); do
    # Generate random filename using /dev/urandom
    # Create 8-character random string using base64 and removing non-alphanumeric chars
    RANDOM_NAME=$(cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 8 | head -n 1)

    # Add .txt extension
    FILENAME="${RANDOM_NAME}.txt"

    # Create the file with some basic content
    echo "Random file #$i - Generated on $(date)" > "$OUTPUT_DIR/$FILENAME"

    # Show progress every 1000 files
    if ((i % 1000 == 0)); then
        echo "Created $i files..."
    fi
done

echo "Successfully created $TOTAL_FILES files in $OUTPUT_DIR/"
echo "Directory size: $(du -sh $OUTPUT_DIR)"

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

1.0.117

Platform

Anthropic API

Operating System

linux

Terminal/Shell

kosole (linux)

Additional Information

_No response_