xlsx

xlsx is a skill for Claude Code from bobmatnyc/claude-mpm-skills. It costs 9 tokens per session (894 once invoked), scanned A, original, MIT.

A guide to reading, editing, formatting, and creating Excel files in code. It covers individual cells, multiple sheets, formulas, and table-like data handled with Python.

In plain words
What is it for?
Use it to import and export XLSX files, change cell formatting, add formulas, and work with spreadsheet data through Python.
Why use it?
It removes the need to edit spreadsheets manually when the same operation must be repeated or applied to large datasets.

Skill for Claude Code

Written for Claude Code: disable-model-invocation in frontmatter.

not rated 74repo 1mo ago A scan Socket: passSnyk: passSkillSpector: pass 9 tokens original MIT

Good fit Use it to import and export XLSX files, change cell formatting, add formulas, and work with spreadsheet data through Python.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/bobmatnyc/claude-mpm-skills/xlsx
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add bobmatnyc/claude-mpm-skills --skill xlsx
Clone the repo
git clone --depth 1 https://github.com/bobmatnyc/claude-mpm-skills

Made for: Claude Code.

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/skills/bobmatnyc/claude-mpm-skills/xlsx/github.svg)](https://agentmods.dev/skills/bobmatnyc/claude-mpm-skills/xlsx)
Your own site
<a href="https://agentmods.dev/skills/bobmatnyc/claude-mpm-skills/xlsx"><img src="https://agentmods.dev/badge/skills/bobmatnyc/claude-mpm-skills/xlsx/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for xlsx

Your own site · 80×15
<a href="https://agentmods.dev/skills/bobmatnyc/claude-mpm-skills/xlsx"><img src="https://agentmods.dev/badge/skills/bobmatnyc/claude-mpm-skills/xlsx.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 9 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 894 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • Socket pass 16 Apr 2026
  • Snyk pass 16 Apr 2026
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 $0.00009 $0.00894
Opus 5 $0.00005 $0.00447
Sonnet 5 $0.00002 $0.00179
Haiku 4.5 $0.00001 $0.00089

Measured 8d ago against content hash c25e2b07c165, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, 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 8d 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.

universal/data/xlsx/SKILL.md · 163 lines

How it starts

The opening of the file, as written. The whole thing — 163 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Excel/XLSX Manipulation

Working with Excel files programmatically.

Python (openpyxl)

Reading Excel

from openpyxl import load_workbook

wb = load_workbook('data.xlsx')
ws = wb.active  # Get active sheet

# Read cell
value = ws['A1'].value

# Iterate rows
for row in ws.iter_rows(min_row=2, values_only=True):
    print(row)

Writing Excel

from openpyxl import Workbook

wb = Workbook()
ws = wb.active
ws.title = "Data"

# Write data
ws['A1'] = 'Name'
ws['B1'] = 'Age'
ws.append(['John', 30])
ws.append(['Jane', 25])

wb.save('output.xlsx')

Formatting

from openpyxl.styles import Font, PatternFill

# Bold header
ws['A1'].font = Font(bold=True)

# Background color
ws['A1'].fill = PatternFill(start_color="FFFF00", fill_type="solid")

# Number format
ws['B2'].number_format = '0.00'  # Two decimals

Formulas

# Add formula
ws['C2'] = '=A2+B2'

# Sum column
ws['D10'] = '=SUM(D2:D9)'

Python (pandas)

Reading Excel

import pandas as pd

# Read sheet
df = pd.read_excel('data.xlsx', sheet_name='Sheet1')

# Read multiple sheets
dfs = pd.read_excel('data.xlsx', sheet_name=None)

Writing Excel

# Write DataFrame
df.to_excel('output.xlsx', index=False)

# Multiple sheets
with pd.ExcelWriter('output.xlsx') as writer:
    df1.to_excel(writer, sheet_name='Sheet1')
    df2.to_excel(writer, sheet_name='Sheet2')

Data Transformation

# Filter
filtered = df[df['Age'] > 25]

# Group by
grouped = df.groupby('Department')['Salary'].mean()

# Pivot
pivot = df.pivot_table(values='Sales', index='Region', columns='Product')

JavaScript (xlsx)

import XLSX from 'xlsx';

// Read file
const workbook = XLSX.readFile('data.xlsx');
const sheetName = workbook.SheetNames[0];
const worksheet = workbook.Sheets[sheetName];

// Convert to JSON
const data = XLSX.utils.sheet_to_json(worksheet);

// Write file
const newWorksheet = XLSX.utils.json_to_sheet(data);
const newWorkbook = XLSX.utils.book_new();
XLSX.utils.book_append_sheet(newWorkbook, newWorksheet, 'Data');
XLSX.writeFile(newWorkbook, 'output.xlsx');

Read the full file on GitHub · 163 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. 8d ago First seen · 163 lines · 9 tokens per session scan A c25e2b07c165

Subscribe to this mod's changes

xlsx is a skill published in the GitHub repository bobmatnyc/claude-mpm-skills (74 stars, last pushed 1mo ago), licensed MIT. It adds 9 tokens to every session and 894 once invoked, about $0.0000 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 2026-09-03.