Here's a sensitive Bollinger Band indicator for TradingView Pine Script that triggers when price touches the upper or lower bands:

This script includes:

1. Adjustable sensitivity threshold (0.01% to 1%)
2. Visual signals when price touches bands
3. Alert conditions for notifications
4. Strategy entries for backtesting
5. Customizable Bollinger Band parameters

You can adjust the sensitivity parameter to make it more or less responsive to price movements near the bands.