---
name: mohitagw15856/spreadsheet-audit-live
source: https://app.decimal.ai/s/mohitagw15856-spreadsheet-audit-live@1/SKILL.md
source_sha256: b4461d313501
---

# Spreadsheet Audit (Live)

Spreadsheets fail silently — the SUM that stops at row 40, the hardcoded 1.1 typed over a formula, the column that's monthly in one section and annual in another. In Claude Cowork this skill opens the *actual file* in the sandbox and traces the real formulas, so the mistake is caught before the meeting corrects it.

## What This Skill Produces

- **Findings ranked by damage** — each with cell location, what's wrong, and what it's currently mis-stating
- **The verified/suspect ledger** — which load-bearing outputs were traced clean and which remain unverified (unverified ≠ wrong; the label is the honesty)
- **The fix list** — ordered, with make-it-robust upgrades where they matter
- **A findings artifact** — the above as a shareable report, plus (on request) a corrected copy of the sheet

## Required Inputs

Ask for these if not provided:
- **The sheet** — a Drive file/link or an uploaded `.xlsx`; the audit needs the real formulas, not a screenshot
- **The stakes** — what decision it feeds (budget approval? pricing? a board number?) — depth and ranking follow the damage potential
- **Growth pattern** — does data get appended? The fragility check keys on it

## Framework: The Hunt Rules

1. **Hardcode hunt first** — constants typed over formulas: invisible, wrong-forever. Flag every constant where a column is otherwise formulaic.
2. **Range-edge check on every aggregate** — SUM/AVERAGE/LOOKUP vs the data's real extent (the stops-at-row-40 error).
3. **Unit & time-grain consistency** — monthly-vs-annual, currency, thousands-vs-units mixes at every junction (tell: a ratio ~12× or ~1000× off).
4. **Trace the load-bearing outputs** — the 3–5 numbers the sheet exists to produce get full precedent traces.

## Execution (Cowork)

1. **Get the file** — via the Google Drive connector, download the sheet (or take the uploaded `.xlsx`). Never audit from values alone.
2. **Open in the sandbox** — use the spreadsheet tooling (the `xlsx` skill / a Python pass with openpyxl) to read **formulas**, not just cached values. Enumerate sheets, named ranges, and the formula map.
3. **Run the hunt rules** programmatically — scan for constants-in-formula-columns, aggregate ranges shorter than the data, and cross-section grain mismatches; trace precedents for the headline outputs.
4. **Rank by damage** — location × what-it-mis-states × the decision it feeds.
5. **Emit the artifact** — findings + verified/suspect ledger + fix list. On request, write a **corrected copy** (never overwrite the original) with the fixes applied and a change log.

Guardrails: read-only on the source unless a corrected copy is explicitly requested, and then only as a new file; label unverified outputs honestly; if the connector/file is unavailable, say so — don't audit a sheet you couldn't open.

## Output Format

A **Spreadsheet Audit** artifact:

### Verdict
`Safe to present / Fix before presenting / Do not trust` — one line why

### Findings (ranked by damage)
| # | Cell/range | Class | What's wrong | Currently mis-stating |
|---|---|---|---|---|

### Verified / suspect ledger
| Output | Traced | Status |
|---|---|---|

### Fix list
1. [fix] — [robust upgrade if relevant]

## Quality Checks
- [ ] Formulas were read from the real file, not inferred from values
- [ ] Every finding names an exact cell/range
- [ ] Load-bearing outputs are each marked verified or suspect (none silently assumed)
- [ ] The original file was not modified; any corrected copy is a new file with a change log
- [ ] The verdict follows the findings, not optimism

## Anti-Patterns
- **Auditing the screenshot** — open the actual formulas.
- **Overwriting the source** — corrections go to a copy.
- **Claiming "looks fine"** without tracing the headline numbers.
- **Cosmetic tidying** dressed up as an audit — protect the decision, not the formatting.

## Example Trigger Phrases
- "Audit the budget model in my Drive before the board call."
- "Check this spreadsheet — why don't the totals add up?"
- "Is this sheet safe to build on? Open it and trace it."
- "Someone left me this model; hunt it for hardcodes in Cowork."