Built for serious spreadsheet work where you need actual Excel files as output, not just data analysis. Handles everything from cleaning messy CSV imports to building financial models with proper formulas. The standout feature is automatic formula recalculation through LibreOffice integration, so your SUM and VLOOKUP formulas actually work when you open the file. Enforces Wall Street color coding standards (blue for inputs, black for formulas) and catches common Excel errors like #REF! and #DIV/0!. Skip this if you just need charts or reports, but essential when deliverable must be a working .xlsx file.
npx skills add https://github.com/anthropics/skills --skill xlsx