Robust PowerPoint generation with shell_agent primary and python-pptx fallback, including directory verification and error debugging
Use this workflow when:
This skill provides two paths:
Before any generation, verify your current working directory:
# Check and record current directory
pwd
# Output should be saved for later reference
# List current contents to establish baseline
ls -la
Important: Save the pwd output. You'll need this to verify where files are created.
Attempt PowerPoint creation via shell_agent first (quickest if successful):
Use shell_agent to create a PowerPoint presentation with:
- Specify the exact number of slides needed
- Define the content/topic for each slide
- Request the file be saved with a clear filename (e.g., presentation.pptx)
- Ask the agent to confirm the full file path after creation
Example task description:
Create a PowerPoint presentation with 10 slides covering [topic]. Each slide should have a title and bullet points. Save it as presentation.pptx and tell me the full file path where you saved it.
If shell_agent returns "unknown error" or fails:
# Capture actual error by adding stderr redirect
# Re-run the task or check previous error output
# Add 2>&1 to any shell commands to see real errors
After 2 failures or opaque errors, switch to Fallback Path (Step 2).
When shell_agent fails, use direct Python execution. Always write script to file first, then execute.
Write a complete Python script using python-pptx:
from pptx import Presentation
from pptx.util import Inches, Pt
# Create presentation
prs = Presentation()
# Slide 1: Title slide
slide_layout = prs.slide_layouts[0]
slide = prs.slides.add_slide(slide_layout)
title = slide.shapes.title
subtitle = slide.placeholders[1]
title.text = "Title Here"
subtitle.text = "Subtitle Here"
# Slide 2+: Content slides
for i in range(2, 11):
slide_layout = prs.slide_layouts[1]
slide = prs.slides.add_slide(slide_layout)
title = slide.shapes.title
title.text = f"Slide {i} Title"
# Add content
content = slide.placeholders[1]
content.text = f"Content for slide {i}"
# Save to current working directory
prs.save('presentation.pptx')
print("File saved to:", os.path.abspath('presentation.pptx'))
Save this script as: create_presentation.py
# Write script to file first, then execute with stderr capture
python create_presentation.py 2>&1 | tee execution_log.txt
# Check for success
if [ -f "presentation.pptx" ]; then
echo "SUCCESS: File created in current directory"
ls -la presentation.pptx
else
echo "FAILED: Check execution_log.txt for errors"
cat execution_log.txt
fi
# Confirm file is where expected
CURRENT_PWD=$(pwd)
FILE_PATH=$(realpath presentation.pptx 2>/dev/null)
if [[ "$FILE_PATH" == "$CURRENT_PWD"* ]]; then
echo "✓ File is in expected directory"
else
echo "⚠ File created elsewhere: $FILE_PATH"
echo "Current directory: $CURRENT_PWD"
fi
PowerPoint files may be created in nested directories. Always search before assuming location:
# Search for all .pptx files in workspace
find . -name "*.pptx" -type f 2>/dev/null
# Search for specific filename
find . -name "presentation.pptx" -type f 2>/dev/null
# If not found, broaden search
find . -name "*.pptx" -type f -mmin -5 2>/dev/null
Once located, bring the file to your known working directory:
# Found path example: ./workspace/task_123/output/presentation.pptx
FOUND_PATH=$(find . -name "presentation.pptx" -type f | head -1)
if [ -n "$FOUND_PATH" ]; then
cp "$FOUND_PATH" .
echo "Copied from: $FOUND_PATH"
else
echo "ERROR: File not found - check Python script execution"
fi
Confirm the file exists and is valid:
# Check file exists and size
ls -la presentation.pptx
# Verify not empty (PowerPoint files should be >1KB minimum)
FILE_SIZE=$(stat -f%z presentation.pptx 2>/dev/null || stat -c%s presentation.pptx 2>/dev/null)
if [ "$FILE_SIZE" -gt 1000 ]; then
echo "✓ File size OK: $FILE_SIZE bytes"
else
echo "⚠ WARNING: File may be empty or corrupted ($FILE_SIZE bytes)"
fi
# Check file type
file presentation.pptx
Use these when errors occur:
# Capture full error output from any command
python script.py 2>&1 | tee error_log.txt
# Check Python is available and python-pptx installed
python -c "from pptx import Presentation; print('python-pptx OK')" 2>&1
# List all .pptx files with details
find . -name "*.pptx" -type f -exec ls -la {} \; 2>/dev/null
# Check write permissions in current directory
touch test_write.txt && rm test_write.txt && echo "Write OK" || echo "Write FAILED"
# Show full path context
pwd
ls -la
| Pitfall | Solution |
|---|---|
| shell_agent returns opaque errors | Switch to Fallback Path after 2 failures; add 2>&1 for real errors |
| Assuming file is in current directory | Always run find command before proceeding |
| Script runs but file not found | Check python script's save path; verify working directory |
| File is 0 bytes | Re-run Python script; check for exceptions in error log |
| Multiple .pptx files found | Use specific search: find . -name "*presentation*.pptx" -mmin -5 |
| No module named pptx | Install: pip install python-pptx or use execute_code_sandbox |
Start
│
├─> Try shell_agent (Step 1)
│ │
│ ├─> Success with path confirmed → Go to Step 4
│ │
│ └─> Failure or opaque error (2×) → Switch to Fallback
│ │
│ └─> Direct Python (Step 2)
│ │
│ ├─> Success → Go to Step 4
│ │
│ └─> Failure → Debug with commands above
│
└─> Always: locate with find, copy, verify (Steps 3-5)
# Pre-check
pwd # Save output: /workspace/current_task
# Try shell_agent (via task delegation)
# If fails after 2 attempts:
# Create Python script
cat > create_presentation.py << 'EOF'
from pptx import Presentation
prs = Presentation()
# ... add slides ...
prs.save('presentation.pptx')
print("Saved to:", __import__('os').path.abspath('presentation.pptx'))
EOF
# Execute with error capture
python create_presentation.py 2>&1 | tee exec.log
# Locate (may be in subdirectory)
find . -name "presentation.pptx" -type f
# Output: ./generated/presentation.pptx
# Copy to working directory
cp ./generated/presentation.pptx .
# Verify
ls -la presentation.pptx
file presentation.pptx
| Problem | Command | Expected Output | Action |
|---|---|---|---|
| python-pptx not installed | python -c "from pptx import Presentation" | ImportError | Install: pip install python-pptx |
| Permission denied | touch test.txt && rm test.txt | Success | Check directory permissions with ls -la |
| File not found | find . -name "*.pptx" -type f | Path or empty | Re-run script; check error log |
| Opaque error | python script.py 2>&1 | Real exception | Fix Python code based on error message |
| Multiple files | find . -name "*.pptx" -type f | Multiple paths | Use -mmin -5 to find recent files |
Use direct Python (Step 2) immediately when: