This is a personal, non-commercial side project I put together to learn — not a product or service, and not connected to any company I work with.
Post #10 asked a simple question: if a balance sits above the agreed operating buffer for weeks, who actually notices — and what does that silence cost? Below is a small prototype that answers the second half of that question with sample data.
The script doesn't decide anything. It just puts the one number — what the excess could have earned — next to the balance that was already sitting there in plain sight.
The sample data
Six accounts, each with a balance, an agreed buffer, and the rate a routine cash sweep could reasonably earn. Two of them are carrying meaningfully more than their buffer calls for.
| ID | Account | Balance | Buffer | Excess | Alt. rate | Status |
|---|---|---|---|---|---|---|
| AC-01 | Operating Account | €340,000 | €150,000 | €190,000 | 3.00% | Flagged |
| AC-02 | Payroll Account | €85,000 | €80,000 | €5,000 | 3.00% | Clear |
| AC-03 | VAT Reserve | €60,000 | €60,000 | €0 | 3.00% | Clear |
| AC-04 | Project Account | €120,000 | €40,000 | €80,000 | 3.00% | Flagged |
| AC-05 | Marketing Account | €45,000 | €40,000 | €5,000 | 3.00% | Clear |
| AC-06 | Contingency Reserve | €200,000 | €200,000 | €0 | 3.00% | Clear |
How it works
Try it yourself
1 — Clone the repository
2 — Add your own balances (optional)
3 — Run it
4 — Read the output
What it's built from
Data source
A plain CSV of account balances — no live banking connection, no API keys, nothing beyond sample data.
Calculation
Standard Python, no external dependencies — subtraction and a rate applied to the excess.
Configurable threshold
The flagging amount and the alternative rate are both command-line arguments, not hardcoded.
Read-only by design
The script only reads and reports. It doesn't move money, connect to a bank, or take any action on its own.
What's in the repository
The same personal, non-commercial repository as the earlier demos in this series:
- idle_cash_agent.py — the full script used above
- data/account_balances.csv — the sample data shown in this walkthrough
- The CFO Report Agent from Post #2, the Invoice Agent from Post #3, and the FX Monitoring Agent from Post #9
Follow the series
Post #11 stays with cash — this time on the other side of the ledger: which invoices actually get paid first, and why the answer usually has nothing to do with the due date printed on them.
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