spreadsheet-validated-execution

Direct Python Execution for Spreadsheet Tasks

When to Use This Skill

Use this skill for spreadsheet operations that require verified source data:

• Before processing: Verify data sources are accessible and contain expected data
• Reading or writing complex Excel files with multiple sheets
• Applying formulas, formatting, or data transformations
• Working with openpyxl, pandas, or similar libraries
• The operation involves multiple steps that could exceed agent step limits
• You need precise control over error handling and debugging
• Complex scripts benefit from file-based execution for better reliability

Critical: Data Source Validation First

Always validate data availability before attempting spreadsheet operations. This prevents wasted iterations on unavailable data.

Pre-Execution Validation Checklist

1. Verify source accessibility: Test connection to data URLs/files before building processing scripts
2. Confirm data format: Ensure source data matches expected structure (columns, sheets, file type)
3. Check data completeness: Validate required fields/rows are present
4. Identify fallback sources: Document alternative data sources if primary is unavailable

Validation Script Pattern

import sys
import os
from pathlib import Path

def validate_source(source_path, required_fields=None):
    """Validate data source before processing"""
    if not Path(source_path).exists():
        return False, f"Source file not found: {source_path}"
    
    try:
        # Check file is readable and non-empty
        if os.path.getsize(source_path) == 0:
            return False, "Source file is empty"
        
        if required_fields:
            # Validate structure using pandas
            import pandas as pd
            df = pd.read_excel(source_path, nrows=1)
            missing = set(required_fields) - set(df.columns)
            if missing:
                return False, f"Missing required columns: {missing}"
        
        return True, "Source validated"
    except Exception as e:
        return False, f"Validation error: {str(e)}"

# Usage
valid, message = validate_source('input.xlsx', ['ID', 'Date', 'Value'])
if not valid:
    print(f"ABORT: {message}", file=sys.stderr)
    sys.exit(1)
print(f"OK: {message}")