This is a submission for the Gemma 4 Challenge: Build with Gemma 4
TL;DR: Vitreus is a spreadsheet agent that lets you ask natural-language questions of CSV and XLSX workbooks, then uses Gemma 4 to return an auditable JSON action manifest. The manifest can highlight rows, write values, and add formulas; Vitreus then applies those changes to a CSV snapshot or a real .xlsx file with colors and formulas preserved.
I built it because spreadsheets are where a lot of real business logic lives: budgets, project trackers, sales forecasts, invoices, HR reviews, and messy exported reports. But the moment you ask an AI assistant to "just update the sheet," you run into a trust problem: what exactly did it change, and why?
Vitreus answers that by splitting the job in two:
Gemma 4 reasons about the workbook.
