Things to make / Recipe 10 of 13 · Organize
Turn a receipt stack into a budget
See each purchase and check every total against its source.
- About 16 minutes
- For someone who wants a first look at a small stack of typed receipts.
- Runs in Claude Code and OMP
What the agent made
Ran it for real with Claude Code 2.1.292 and OMP 18.8.5 on 2026-10-08, in an empty session with no saved memory. Your result will differ.
| date | store | item | amount | category | source_filename |
|---|---|---|---|---|---|
| 2025-05-05 | Pebble Pantry | Oats | 4.50 | Groceries | receipt-01.txt |
| 2025-05-05 | Pebble Pantry | Dried berries | 3.25 | Groceries | receipt-01.txt |
| 2025-05-05 | Pebble Pantry | Lemon | 2.25 | Groceries | receipt-01.txt |
| 2025-05-06 | Lantern Stationery | Notebook | 6.40 | Office Supplies | receipt-02.txt |
| 2025-05-06 | Lantern Stationery | Pencil | 1.60 | Office Supplies | receipt-02.txt |
| 2025-05-07 | Pebble Pantry | Bread | 3.00 | Groceries | receipt-03.txt |
| 2025-05-07 | Pebble Pantry | Milk | 2.00 | Groceries | receipt-03.txt |
| 2025-05-07 | Pebble Pantry | Apple | 1.50 | Groceries | receipt-03.txt |
| 2025-05-08 | Beacon Hardware | Batteries | 9.00 | Hardware | receipt-04.txt |
| 2025-05-08 | Beacon Hardware | Tape | 4.00 | Hardware | receipt-04.txt |
Open the whole file · Also made: totals.txt
The same prompt in OMP made its own version: open what OMP made. Two runs, two different results: that is normal.
Make your own
Get the files
Download the practice folder (ZIP)
Unzip it: you get a folder called
cli-practicewith 4 fictional files. Download four fictional typed receipts in receipts/ with 10 priced lines total.Open your agent in that folder
Open a terminal in
cli-practiceand typeclaudeoromp --approval-mode always-ask. First time? Set up in about five minutes, with steps for Mac, Windows, and Linux.Paste this prompt
Work only inside this practice folder. Read the text files in receipts/. Write spending.csv with date, store, item, amount, category, source filename: one row per priced item, including any explicitly listed tax or fee. Use two-decimal dollar amounts and no invented prices. Write totals.txt with totals by category and by receipt, a grand total, and any mismatch with printed subtotals or totals. Calculate using Python's standard library Decimal. Do not alter input files, use the network, install packages, send messages, or read outside this folder. Output must work offline.
The prompt asks the agent to stay in this folder; it cannot enforce that. Read each file change and command before you approve it.
Check it yourself
Open
cli-practice/spending.csvin a spreadsheet app or text editor, then:Human check: Add the three amounts on receipt-01.txt by hand, compare its receipt total in totals.txt, and match its three CSV rows.
When we checked the recording above: Read receipt-01 and all three matching CSV rows: 4.50 + 3.25 + 2.25 = 10.00, agreeing with printed subtotal, printed total, and totals.txt; four receipt totals sum to 37.50. All input files unchanged.
Why an agent, not a chat window
An agent reads several local documents, extracts itemized rows, and writes a reconciled table you can open in a spreadsheet.