August 23, 2026
xlsx
Lets an AI agent create, edit and analyze spreadsheets with live formulas and no errors.
- Ecosystem
- Claude
- Skill category
- Data
- Creator / organization
- Anthropic
- Origin
- United States
What it is
xlsx is the Skill in Anthropic's official skills repository for spreadsheets, covering .xlsx, .xlsm, .csv and .tsv files. It follows a few firm rules. Results are written as Excel formulas instead of values computed in Python, so they update when you change the inputs. After any formula work, the file is recalculated in LibreOffice to confirm there are no errors. When editing an existing file, it keeps the file's formatting and conventions. Financial models use the standard color code: blue for hard-coded inputs, black for formulas, green for links to other sheets, red for external links, and yellow fill for key assumptions. Sources and assumptions go in cell comments or neighboring cells.
Who it's for:people who build budgets, financial models or data cleanups, especially if they will keep working in Excel afterward.
Before you start: written for Claude. It needs Python (openpyxl, pandas) and LibreOffice. Like docx, it uses Anthropic's proprietary license: the source is viewable, but it is not open source.
Based on the project's public documentation. Not tested by AI Inspiration World.