excel-model-workbook
An Agent Skill for building, auditing and grading Excel model workbooks.
- Build: a short standard for workbooks others must trust: inputs, calculations and outputs
separated, one formula pattern per row, no number buried in a formula, a controls sheet with a
single "all checks pass" cell, a documentation sheet with a version stamp.
- Audit: a dependency-free command-line tool that reads
.xlsx / .xlsm files without Excel
and reports errors (root causes first), circular references, hard-coded numbers, broken formula
patterns, failing or fake controls and stale stored values; it also traces precedents and
dependents across sheets.
- Grade: compare a submission with a reference under a rubric, with tolerance,
formula-required items, partial credit and consistent treatment of carried-forward errors. The
output is evidence for a human grader, never a final grade.
Install
skills install @spboucher/excel-model-workbook --client claude-code
or copy the folder into your agent's skills directory (for Claude Code: ~/.claude/skills/).
Use
node scripts/xlsx.mjs --help
node scripts/xlsx.mjs report model.xlsx
node scripts/xlsx.mjs grade reference.xlsx student.xlsx --rubric assets/rubric.example.json
Node.js 20 or later, no npm install. Nothing in a workbook is executed; the tool writes only
the report or evidence file you ask for, and never overwrites.
Contents
| Path | What |
|---|
SKILL.md | Instructions for the agent |
scripts/xlsx.mjs | Command-line auditor, 14 commands, JSON output |
scripts/lib/ | Engine, identical to the one in @spboucher/xlsx-audit-mcp |
references/modeling-standard.md | Layout standard and an openpyxl skeleton |
references/audit-procedure.md | How to read each result |
references/grading.md | Rubric format and grading policies |
references/defects.md | Defect catalogue |
assets/rubric.example.json | Rubric template |
Limits
.xlsx and .xlsm only. The built-in evaluator covers arithmetic, comparisons, SUM,
AVERAGE, MIN, MAX, ROUND, IF, references and plain defined names; every other formula
is read from the result stored in the file, and the tool states the share it could not recompute.
Macros, external links, charts, pivot tables, conditional formatting and data validation are not
read. A clean report shows that mechanical defects are absent, not that the model is right.
The same engine is available as an MCP server: @spboucher/xlsx-audit-mcp.
License
MIT