Key Functionality & Customization - Llama Index provides a customizable extraction review template for specific data like receipts and invoices [1] - The template allows users to focus on schema development rather than building scaffolding [2] - Users can update front-end schemas to reflect changes in the data extraction process [3] - The system flags fields with low confidence, enabling efficient review and validation [4] - Users can deploy custom extraction agents with validation on Llama Cloud [6] Deployment & Data Handling - The deployed app can have a distinct production dataset compared to the local environment [5] - Users can re-upload data to improve extraction results and achieve valid states [4][6] Application & Validation - The system is designed for messy and hard-to-read documents with multiple line items and taxes [1] - The custom extraction agent includes validation to ensure accuracy [6]