Data Analysis Skill

Overview

This skill analyzes user-uploaded Excel/CSV files using DuckDB — an in-process analytical SQL engine. It supports schema inspection, SQL-based querying, statistical summaries, and result export, all through a single Python script.

Core Capabilities

• Inspect Excel/CSV file structure (sheets, columns, types, row counts)
• Execute arbitrary SQL queries against uploaded data
• Generate statistical summaries (mean, median, stddev, percentiles, nulls)
• Support multi-sheet Excel workbooks (each sheet becomes a table)
• Export query results to CSV, JSON, or Markdown
• Handle large files efficiently with DuckDB's columnar engine

Workflow

Step 1: Understand Requirements

When a user uploads data files and requests analysis, identify:

• File location: Path(s) to uploaded Excel/CSV files under /mnt/user-data/uploads/
• Analysis goal: What insights the user wants (summary, filtering, aggregation, comparison, etc.)
• Output format: How results should be presented (table, CSV export, JSON, etc.)
• You don't need to check the folder under /mnt/user-data

Step 2: Inspect File Structure

First, inspect the uploaded file to unde…