Anthropic XLSX Skill

npx degit anthropics/skills/skills/xlsx ~/.claude/skills/xlsx

The xlsx skill handles everything spreadsheet-shaped — .xlsx, .xlsm, .csv, .tsv. It picks the right Python library (openpyxl, pandas, xlsxwriter) based on what you’re trying to do.

What it can do

• Generate spreadsheets from scratch with formatting and formulas
• Edit existing files — add columns, compute formulas, restructure
• Charting — bar, line, pie, etc., as embedded chart objects (editable in Excel)
• Format — conditional formatting, number formats, cell styles
• Clean — fix malformed rows, misplaced headers, junk data, normalize columns
• Convert — between .xlsx, .csv, .tsv

Where it shines

• Quarterly / monthly reports with consistent chart styling
• Data cleaning of exported tables that arrived messy
• Template-driven spreadsheets where the same structure is filled per client
• Migration / restructuring of legacy spreadsheet files

Won’t trigger when

• The deliverable is a Word doc, HTML report, Python script, or DB pipeline — even if tabular data is involved. It’s strictly for spreadsheet-final outputs.

Composes with

• pdf — convert charts and sheets into a PDF report
• pptx — embed chart images into a deck
• brand-guidelines — apply house colors and fonts

Use xlsx to clean this messy CSV — fix misplaced headers, drop junk
rows, normalize date columns, then build a quarterly revenue chart on
a new sheet and export as .xlsx.