xlsx

Use this skill any time a spreadsheet file is the primary input or output. This means any task where the user wants to: open, read, edit, or fix an existing .xlsx, .xlsm, .xltx, .csv, or .tsv file (e.g., adding columns, computing formulas, formatting, charting, cleaning messy data); create a new spreadsheet from scratch or from other data sources; or convert between tabular file formats. Trigger especially when the user references a spreadsheet file by name or path — even casually (like "the xlsx in my downloads") — and wants something done to it or produced from it. Also trigger for cleaning or restructuring messy tabular data files (malformed rows, misplaced headers, junk data) into proper spreadsheets. The deliverable must be a spreadsheet file. Do NOT trigger when the primary deliverable is a Word document, HTML report, standalone Python script, database pipeline, or Google Sheets API integration, even if tabular data is involved.

Agent Skill from anthropics/skills

Copilot Studio

Passes documented load rules

No documented load rule failed.

Microsoft 365 Copilot Preview, Frontier tenants only

Needs changes

Fails: Directory depth is at most 3 (M365-DEPTH)
deepest file is 5 folders down
rule · Microsoft 365 Copilot: Support matrix
Fails: Every file has a supported file type (M365-FILE-TYPES)
39 unsupported: scripts/office/schemas/ISO-IEC29500-4_2016/dml-chart.xsd, scripts/office/schemas/ISO-IEC29500-4_2016/dml-chartDrawing.xsd, scripts/office/schemas/ISO-IEC29500-4_2016/dml-diagram.xsd, scripts/office/schemas/ISO-IEC29500-4_2016/dml-lockedCanvas.xsd, scripts/office/schemas/ISO-IEC29500-4_2016/dml-main.xsd, scripts/office/schemas/ISO-IEC29500-4_2016/dml-picture.xsd, scripts/office/schemas/ISO-IEC29500-4_2016/dml-spreadsheetDrawing.xsd, scripts/office/schemas/ISO-IEC29500-4_2016/dml-wordprocessingDrawing.xsd, …
rule · Microsoft 365 Copilot: Supported file and script types

Warnings (don't change the verdict):

Warning: No sign of network access, package installs or authenticated calls (M365-SANDBOX)
SKILL.md mentions pip/uv install
rule · Microsoft 365 Copilot: Script execution sandbox
Warning: No sign of network access, package installs or authenticated calls (M365-SANDBOX)
scripts: scripts/office/soffice.py (sockets)
rule · Microsoft 365 Copilot: Script execution sandbox

An agent can have at most 8 skills. Custom skills aren't available in tenants that use Microsoft Purview Information Barriers.

Compatible isn't the same as safe. These verdicts only say whether a skill's files follow Microsoft's documented load rules. The checker reads files and never runs them, and it doesn't review what a skill or its scripts actually do. Read a skill's instructions and scripts before you add it to an agent.

Standards signals

Meets the agentskills.io required fields.

Frontmatter	Present and parsed Spec: frontmatter
name	Meets the spec (1-64 chars, a-z 0-9 hyphens) Spec: name
description	Present, 1-1,024 characters Spec: description
compatibility	Absent or under 500 characters Spec: compatibility
Name matches folder	Yes (`xlsx`) Spec: name

Observed from the public SKILL.md at the commit above on 2026-10-23. Not a certification: AAIF and the Agent Skills project don't certify skills. Validate your own skill with skills-ref validate.

Source repo	anthropics/skills
Path	skills/xlsx/SKILL.md
Commit checked	`dbd4588f9e10`
Repo license	No repo-wide license file · we list metadata only
Skill license file	other
Files	53
Scripts	12 (12 scanned for the sandbox heuristic)
Instructions	7,504 characters
Deepest folder	5 below the skill folder
Installs (skills.sh)	186,306
Rules version	2026-10-22

Re-check the latest version How skill checks work

Is this wrong or out of date? Email us. Skills data built 2026-10-23; rules as of 2026-10-22.

Rule-based checks of public files against Microsoft's documented load rules, not tested in Copilot Studio or Microsoft 365 Copilot. Independent project, not affiliated with Microsoft.