Install
/plugin marketplace add anthropics/skills
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XLSX is an Agent Skill for any task where a spreadsheet is the primary input or output. It can open, read, edit, or fix existing .xlsx, .xlsm, .csv, and .tsv files by adding columns, computing formulas, formatting, charting, and cleaning messy data, as well as create new spreadsheets or convert between tabular formats. Use it when the deliverable is a spreadsheet; it stands aside when the real output is a Word doc, HTML report, standalone script, or database pipeline.