Expense Anomaly Detector with Slack Alert

## Setup Instructions

1. **API Config**: Configure the `Fetch Recent Expenses` node with your expense management API (e.g., Expensify, Brex) or replace with a Database node.
2. **Thresholds**: Adjust the logic in `Analyze Anomaly` code node to define what constitutes an anomaly for your business.
3. **Slack**: Connect your Slack account and set the channel names for alerts.
4. **Logging**: Create a Google Sheet with columns `merchant`, `amount`, `reason` and connect it to the `Log to Google Sheets` node.

**Logic**: This workflow fetches daily expenses, filters out small amounts, checks against a dynamic threshold, and alerts Slack if an anomaly is found.