xlsx

xlsx is a command for Claude Code, Gemini CLI from mfmezger/ai_agent_dotfiles. It costs 199 tokens per session (2,816 once invoked), scanned A, original, MIT.

A set of instructions for working with spreadsheet files such as Excel workbooks, CSV files, and TSV files. It covers reading, editing, cleaning, formulas, formatting, charts, and financial models.

In plain words
What is it for?
Creating or updating spreadsheet files, calculating values, cleaning data, applying formatting, and making charts.
Why use it?
It provides rules for producing reliable spreadsheets, including avoiding formula errors and preserving an existing template's design.

Command for Claude CodeGemini CLI

Written for Gemini CLI and Claude Code: installed under .gemini/, but also a Claude Code command (commands/*.md).

Needs its repository: it runs a file that does not travel with it, so clone the repository first. The line is python scripts/recalc.py output.xlsx.

Install

Getting it into your agent

It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.

Clone the repo
git clone --depth 1 https://github.com/mfmezger/ai_agent_dotfiles
agentmods
npx agentmods add commands/mfmezger/ai_agent_dotfiles/xlsx

Made for: Claude Code, Gemini CLI.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for xlsx

README.md
[![agentmods](https://agentmods.dev/badge/commands/mfmezger/ai_agent_dotfiles/xlsx.svg)](https://agentmods.dev/commands/mfmezger/ai_agent_dotfiles/xlsx)
Your own site
<a href="https://agentmods.dev/commands/mfmezger/ai_agent_dotfiles/xlsx"><img src="https://agentmods.dev/badge/commands/mfmezger/ai_agent_dotfiles/xlsx.svg" alt="Measured on agentmods" height="20"></a>
Per session 199 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 2,816 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00199 $0.02816
Opus 5 $0.00100 $0.01408
Sonnet 5 $0.00040 $0.00563
Haiku 4.5 $0.00020 $0.00282

Measured 6d ago against content hash 4942b0d46e35, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

xlsx scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 6d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

gemini/.gemini/commands/xlsx.md · 319 lines

How it starts

The opening of the file, as written. The whole thing — 319 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Requirements for Outputs

All Excel files

Professional Font

  • Use a consistent, professional font (e.g., Arial, Times New Roman) for all deliverables unless otherwise instructed by the user

Zero Formula Errors

  • Every Excel model MUST be delivered with ZERO formula errors (#REF!, #DIV/0!, #VALUE!, #N/A, #NAME?)

Preserve Existing Templates (when updating templates)

  • Study and EXACTLY match existing format, style, and conventions when modifying files
  • Never impose standardized formatting on files with established patterns
  • Existing template conventions ALWAYS override these guidelines

Financial models

Color Coding Standards

Unless otherwise stated by the user or existing template

Industry-Standard Color Conventions
  • Blue text (RGB: 0,0,255): Hardcoded inputs, and numbers users will change for scenarios
  • Black text (RGB: 0,0,0): ALL formulas and calculations
  • Green text (RGB: 0,128,0): Links pulling from other worksheets within same workbook
  • Red text (RGB: 255,0,0): External links to other files
  • Yellow background (RGB: 255,255,0): Key assumptions needing attention or cells that need to be updated

Number Formatting Standards

Required Format Rules
  • Years: Format as text strings (e.g., "2024" not "2,024")
  • Currency: Use $#,##0 format; ALWAYS specify units in headers ("Revenue ($mm)")
  • Zeros: Use number formatting to make all zeros "-", including percentages (e.g., "$#,##0;($#,##0);-")
  • Percentages: Default to 0.0% format (one decimal)
  • Multiples: Format as 0.0x for valuation multiples (EV/EBITDA, P/E)
  • Negative numbers: Use parentheses (123) not minus -123

Formula Construction Rules

Assumptions Placement
  • Place ALL assumptions (growth rates, margins, multiples, etc.) in separate assumption cells
  • Use cell references instead of hardcoded values in formulas
  • Example: Use =B5*(1+$B$6) instead of =B5*1.05
Formula Error Prevention
  • Verify all cell references are correct
  • Check for off-by-one errors in ranges
  • Ensure consistent formulas across all projection periods
  • Test with edge cases (zero values, negative numbers)
  • Verify no unintended circular references

Read the full file on GitHub · 319 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 6d ago First seen · 319 lines · 199 tokens per session scan A 4942b0d46e35

Subscribe to this mod's changes

xlsx is a command published in the GitHub repository mfmezger/ai_agent_dotfiles (5 stars, last pushed 1mo ago), licensed MIT. It adds 199 tokens to every session and 2,816 once invoked, about $0.0010 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.