Real use caseWe have not tested this ourselves
Swap a budgeting app for a spreadsheet and an agent
The poster dropped his finance tracking app. He keeps a Google Sheet and uses a Gemini Spark skill: he tells it what he spent, it logs it, and it answers questions about his spending. He says the same idea works for workouts or anything else you track.
Where this comes from
Original post by @RealArsenije on X, Oct 12, 2026. We rewrote it in our own words. The result is what the poster reports.
Read the originalCopy-paste setup
Keep my spending log in the Google Sheet [SHEET NAME] with the columns Date, Amount, Category, Note. When I tell you something like 'lunch 14.50', add a row with today's date and the best category from this list: [CATEGORIES]. When I ask something like 'how much on eating out this month', answer from the sheet and show the total.
Our own prompt, written from what the source describes. We have not tested it yet. Text in [BRACKETS] is what you replace.