Direct Python Execution for Spreadsheet and Document Tasks
When to Use This Skill
Use direct run_shell with Python scripts for structured document operations when:
- Spreadsheets: Reading or writing complex Excel files with multiple sheets, applying formulas, formatting, or data transformations
- PDFs: Generating PDF checklists, reports, invoices, or forms with precise layout control
- Documents: Creating Word documents, HTML reports, or other structured output formats
- Complex Operations: The task involves multiple steps that could exceed agent step limits
- Precision Needed: You need precise control over error handling, debugging, and library imports
Why Direct Execution?
The shell_agent tool can:
- Hit maximum step limits on complex multi-step operations
- Produce unexplained errors on formatting operations
- Fail on intricate reads/writes due to iterative parsing
- Fail to parse heredoc syntax correctly, causing 'unknown error' failures
Direct run_shell with Python is more reliable because it:
- Executes in a single step with no iteration limits
- Provides clearer, immediate error messages
- Handles complex operations without step constraints
- Gives full control over library imports and execution flow
- Writing scripts to
.pyfiles first avoids shell_agent parsing issues with heredocs
How to Use
Recommended Pattern: Write Script to File First
For complex multi-line scripts, especially when using shell_agent as executor:
# Step 1: Write the Python script to a file
cat > process_document.py << 'EOF'
# Your document/spreadsheet code here
EOF
# Step 2: Execute the script
python3 process_document.py
Alternative Pattern: Inline Heredoc (Simple Scripts Only)
For short, simple scripts when NOT using shell_agent as the executor:
python3 << 'EOF'
# Your code here
EOF
Spreadsheet Examples
Example 1: Read and Transform Excel Data
import pandas as pd
# Load data from specific sheet
df = pd.read_excel('input.xlsx', sheet_name='Revenue')
# Apply transformations
df['Net_Revenue'] = df['Gross_Revenue'] * (1 - df['Tax_Rate'])
# Save results
df.to_excel('output.xlsx', index=False, sheet_name='Processed')
Example 2: Multi-Sheet Operations with openpyxl
from openpyxl import load_workbook
wb = load_workbook('tour_data.xlsx')
# Iterate through sheets
for sheet_name in wb.sheetnames:
ws = wb[sheet_name]
# Apply formatting or calculations
for row in ws.iter_rows(min_row=2, max_col=5):
# Process cells
pass
wb.save('tour_data_processed.xlsx')
Example 3: Complex Formatting Operations
from openpyxl import load_workbook
from openpyxl.styles import Font, PatternFill, Alignment
wb = load_workbook('report.xlsx')
ws = wb.active
# Apply header styling
header_fill = PatternFill(start_color='4472C4', fill_type='solid')
header_font = Font(bold=True, color='FFFFFF')
for cell in ws[1]:
cell.fill = header_fill
cell.font = header_font
cell.alignment = Alignment(horizontal='center')
wb.save('report_formatted.xlsx')
PDF Generation Examples
Example 4: Generate PDF Checklist with ReportLab
from reportlab.lib.pagesizes import letter
from reportlab.pdfgen import canvas
from reportlab.lib.units import inch
def create_checklist(pdf_path, items):
c = canvas.Canvas(pdf_path, pagesize=letter)
width, height = letter
# Title
c.setFont("Helvetica-Bold", 16)
c.drawString(1*inch, height - 1*inch, "Safety Checklist")
# Checklist items
c.setFont("Helvetica", 12)
y_position = height - 1.5*inch
for i, item in enumerate(items, 1):
checkbox_x = 1*inch
text_x = 1.3*inch
c.drawString(checkbox_x, y_position, "☐") # Empty checkbox
c.drawString(text_x, y_position, f"{i}. {item}")
y_position -= 0.3*inch
# New page if needed
if y_position < 1*inch:
c.showPage()
y_position = height - 1*inch
c.save()
print(f"Created checklist: {pdf_path}")
# Usage
items = [
"Verify equipment is powered off",
"Check safety gear is available",
"Inspect work area for hazards",
"Confirm emergency contacts are posted"
]
create_checklist('safety_checklist.pdf', items)
Example 5: Generate PDF Report with Tables
from reportlab.lib import colors
from reportlab.lib.pagesizes import letter
from reportlab.platypus import SimpleDocTemplate, Table, TableStyle, Paragraph, Spacer
from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle
from reportlab.lib.units import inch
def create_report(pdf_path, title, data, column_headers):
doc = SimpleDocTemplate(pdf_path, pagesize=letter,
rightMargin=0.75*inch, leftMargin=0.75*inch,
topMargin=0.75*inch, bottomMargin=0.75*inch)
elements = []
styles = getSampleStyleSheet()
# Title
title_style = ParagraphStyle('CustomTitle', parent=styles['Heading1'],
fontSize=18, spaceAfter=30, alignment=1)
elements.append(Paragraph(title, title_style))
elements.append(Spacer(1, 0.25*inch))
# Table
table_data = [column_headers] + data
table = Table(table_data, colWidths=[2*inch, 1.5*inch, 1.5*inch])
# Table styling
table.setStyle(TableStyle([
('BACKGROUND', (0, 0), (-1, 0), colors.HexColor('#4472C4')),
('TEXTCOLOR', (0, 0), (-1, 0), colors.whitesmoke),
('ALIGN', (0, 0), (-1, -1), 'CENTER'),
('FONTNAME', (0, 0), (-1, 0), 'Helvetica-Bold'),
('FONTSIZE', (0, 0), (-1, 0), 12),
('BOTTOMPADDING', (0, 0), (-1, 0), 12),
('ROWBACKGROUNDS', (0, 1), (-1, -1), [colors.white, colors.HexColor('#D6DCE4')]),
('GRID', (0, 0), (-1, -1), 0.5, colors.grey),
]))
elements.append(table)
doc.build(elements)
print(f"Created report: {pdf_path}")
# Usage
headers = ['Item', 'Quantity', 'Status']
data = [
['Widget A', '150', 'Complete'],
['Widget B', '200', 'In Progress'],
['Widget C', '75', 'Pending']
]
create_report('status_report.pdf', 'Weekly Status Report', data, headers)
Example 6: PDF with Images and Text (FPDF Alternative)
from fpdf import FPDF
class PDF(FPDF):
def header(self):
self.set_font('Arial', 'B', 15)
self.cell(0, 10, 'Project Documentation', 0, 1, 'C')
self.ln(10)
def footer(self):
self.set_y(-15)
self.set_font('Arial', 'I', 8)
self.cell(0, 10, f'Page {self.page_no()}', 0, 0, 'C')
def create_document(pdf_path, title, sections):
pdf = PDF()
pdf.add_page()
pdf.set_font('Arial', 'B', 16)
pdf.cell(0, 10, title, 0, 1, 'L')
pdf.ln(5)
pdf.set_font('Arial', '', 12)
for section in sections:
pdf.set_font('Arial', 'B', 14)
pdf.cell(0, 10, section['title'], 0, 1)
pdf.set_font('Arial', '', 12)
pdf.multi_cell(0, 6, section['content'])
pdf.ln(5)
pdf.output(pdf_path)
print(f"Created document: {pdf_path}")
# Usage
sections = [
{'title': 'Overview', 'content': 'This document provides...'},
{'title': 'Requirements', 'content': 'The following requirements...'},
{'title': 'Timeline', 'content': 'Project phases are...'}
]
create_document('project_doc.pdf', 'Project Alpha', sections)
Error Handling Pattern
import sys
from reportlab.lib.pagesizes import letter
from reportlab.pdfgen import canvas
try:
c = canvas.Canvas('output.pdf', pagesize=letter)
# Your document operations here
c.drawString(100, 750, "Document content")
c.save()
print("Success: PDF created")
except Exception as e:
print(f"Error: {str(e)}", file=sys.stderr)
sys.exit(1)
Best Practices
- Prefer file-based execution for complex scripts: write to
.pyfile first, then execute viarun_shell - Import only needed libraries to reduce execution time and avoid dependency conflicts
- Print clear success/error messages for debugging
- Save intermediate results for complex multi-step transformations
- Test with small data before scaling to large documents or spreadsheets
- Use appropriate libraries for the task: pandas/openpyxl for spreadsheets, reportlab/fpdf for PDFs
- Clean up temporary script files after execution if they won't be reused
- Use absolute paths or verify working directory to avoid file not found errors
- For PDFs: Build content in memory first, then write to file atomically
When NOT to Use This Skill
- Simple single-cell reads/writes (use shell_agent or basic commands)
- Operations that require interactive user input
- Tasks where you need the agent to iteratively refine the approach
- When the target format has a simpler CLI tool available (e.g.,
pandocfor document conversion)
Common Libraries
| Library | Best For |
|---|---|
openpyxl |
Reading/writing .xlsx files, formatting, formulas |
pandas |
Data manipulation, analysis, merging datasets |
xlrd |
Reading older .xls files (read-only) |
xlsxwriter |
Creating new .xlsx files with advanced formatting |
reportlab |
Professional PDF generation with precise layout control |
fpdf |
Simple PDF creation, easier learning curve |
python-docx |
Creating and editing Word documents |
weasyprint |
HTML/CSS to PDF conversion |
Troubleshooting
Issue: Heredoc syntax fails with 'unknown error' when using shell_agent
- Solution: Write the Python script to a
.pyfile first, then execute it withpython3 script.py. This pattern is significantly more reliable than inline heredoc execution when shell_agent is the executor.
Issue: FileNotFoundError
- Solution: Verify the file path is absolute or relative to the working directory. Use
os.getcwd()to confirm current directory if needed.
Issue: PermissionError
- Solution: Ensure the file is not open in another application. On Linux/Mac, check file permissions with
ls -la.
Issue: ModuleNotFoundError
- Solution: Install required libraries first:
pip install reportlab openpyxl pandas. Some environments may needpip3instead.
Issue: MemoryError on large files
- Solution: Process data in chunks using pandas
chunksizeparameter. For PDFs, create multi-page documents instead of single massive pages.
Issue: Formatting not applying (spreadsheets)
- Solution: Ensure you're modifying cell styles before saving, and use
.copy()for style objects to avoid reference issues.
Issue: PDF text rendering incorrectly
- Solution: Check font encoding. For special characters, use Unicode-compatible fonts or escape special characters. ReportLab supports UTF-8 with proper font configuration.
Issue: PDF layout breaks across pages
- Solution: Use ReportLab's flowable elements (Paragraph, Spacer) which handle page breaks automatically, or manually check y-position and call
showPage()when needed.
Quick Reference: PDF vs Spreadsheet Choice
| Need | Recommended Library |
|---|---|
| Data analysis, calculations | pandas + Excel output |
| Complex cell formatting | openpyxl |
| Professional reports with tables | reportlab (PDF) |
| Simple checklists, forms | fpdf or reportlab |
| Word document output | python-docx |
| HTML to PDF | weasyprint |
| Both data + formatted output | Generate data with pandas, format with reportlab |