Xlsx Generator

This is a solid utility for programmatic Excel file generation in Deno. It handles two main workflows: populating branded templates by finding and replacing placeholders like {{REPORT_TITLE}}, and creating spreadsheets from scratch using JSON specs. The template mode is smart because you can analyze existing files first to see what's replaceable before generating output. Supports formulas, multiple sheets, column widths, and freeze panes. The JSON specification format is straightforward if you've worked with spreadsheet data before. Best for automated reporting workflows where you need consistent formatting or have to churn out monthly reports from the same template. Limited support for pivot tables and charts, and it only handles XLSX, not the older XLS format.

skills.sh installs: 395
GitHub stars: 182
last updated: Aug 21, 2026

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Install

$ npx -y skills add jwynia/agent-skills --skill xlsx-generator --agent claude-code

Installs into .claude/skills of the current project.

Files

XLSX Generator

When to Use This Skill

Use this skill when:

Creating Excel spreadsheets programmatically from data or specifications
Populating branded templates with dynamic content while preserving formatting
Extracting cell data, formulas, and structure from existing XLSX files
Finding and replacing placeholder text like {{TITLE}} or ${date} in cells
Automating spreadsheet generation workflows (reports, data exports, financial statements)

Do NOT use this skill when:

User wants to open/view spreadsheets (use native Excel or viewer)
Complex pivot tables or charts are required (limited support)
Working with older .xls format (XLSX only)
Real-time collaborative editing is needed

Prerequisites

Deno installed (https://deno.land/)
Input XLSX files for template-based operations
JSON specification for scratch generation

Quick Start

Two Modes of Operation

Template Mode: Modify existing branded templates
- Analyze template to find placeholders and structure
- Replace {{PLACEHOLDERS}} with actual values
Scratch Mode: Create spreadsheets from nothing using JSON specifications