# Model Strong

> Convert CSV transaction exports into monthly expense reports. Use when asked to summarize expenses, convert csv spend data, build a monthly spending report, or total transactions by category.

- Skill: `halfmoon-mind/model-strong` (Agent Skill, multi-file: 3 files)
- Install (CLI): `npx skillmds@latest add halfmoon-mind/model-strong`
- Raw SKILL.md: https://api.skillmd.com/api/skills/halfmoon-mind/model-strong/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Data & Analytics
- Author: halfmoon-mind (https://skillmd.com/u/halfmoon-mind)
- Updated: 2026-09-21
- Page: https://skillmd.com/skills/halfmoon-mind/model-strong

---


# Model Strong

Turn a CSV of transactions into a monthly expense report.

## Workflow

1. Confirm the CSV has `date`, `amount`, and `category` columns; ask for a header mapping if not.
2. Parse amounts as decimals; treat parentheses as negative, so `(12.50)` means `-12.50`.
3. Group rows by calendar month and category, then total each group.
4. Flag any single transaction above 500.00 in its own outlier section.
5. Render a markdown table sorted by month, then by descending total.

## Edge cases

- Empty file: report "no transactions" instead of an empty table.
- Duplicate rows: dedupe on (date, amount, description) before totals.
- Mixed currencies: stop and ask which currency to keep.