Document Generation Fallback Workflow (Unicode-Safe)

When to Use

Use this skill when shell_agent returns unknown or unclear errors on complex document generation tasks, especially when:

• Generating documents in multiple formats (e.g., .docx, .pdf, .html)
• The error message doesn't provide clear debugging information
• You need to handle special characters, symbols, or non-ASCII text safely
• PDF generation fails due to LaTeX encoding issues

Core Technique

Instead of delegating the entire document generation to shell_agent, manually split the workflow into discrete, observable steps:

1. Content creation → Use write_file to create source document (Markdown)
2. Unicode sanitization → Preprocess markdown to replace problematic characters before PDF conversion
3. Format conversion with stderr capture → Use run_shell with pandoc for each target format, capturing full stderr output
4. Verification → Check output files exist and are valid

⚠️ Unicode & LaTeX Compatibility Warning

Critical: PDF generation via pandoc typically uses LaTeX (pdflatex or xelatex), which has limited Unicode support. Common problematic characters include:

Step-by-Step Workflow

Step 1: Create Source Content with write_file

Write your document content as Markdown to a temporary source file. This gives you full visibility into the content being generated.

write_file
path: /tmp/document_source.md
content: |
  # Document Title
  
  ## Section 1
  Content here...
  
  ## Section 2
  More content...

Step 2: Sanitize Unicode Characters (Pre-PDF Conversion)

Before PDF conversion, create a sanitized version of your markdown with LaTeX-safe characters:

write_file
path: /tmp/document_source_sanitized.md
content: |
  # Document Title
  
  ## Section 1
  Content here... (with all special chars replaced per table above)

Alternative: Use a shell script to sanitize:

run_shell
command: sed -e 's/—/--/g' -e 's/–/-/g' -e 's/"([^"]*)"/"\1"/g' -e 's/'([^']*)/'\1'/g' /tmp/document_source.md > /tmp/document_source_sanitized.md

Note: Keep the original unsanitized file for DOCX/HTML conversion (these formats handle Unicode better).

Step 3: Convert to Target Formats with run_shell

Use run_shell with explicit pandoc commands for each format. Use sanitized source for PDF, original for other formats.

Critical: Always capture stderr output (2>&1) to diagnose failures before retrying with alternative engines.

run_shell
command: pandoc /tmp/document_source.md -o output.docx

run_shell
command: pandoc /tmp/document_source.md -o output.html

Step 3a: PDF Conversion - Try xelatex First (Best Unicode Support)

Use xelatex as the first engine - it has better Unicode support and is commonly available in containerized environments:

run_shell
command: pandoc /tmp/document_source_sanitized.md --pdf-engine=xelatex -o output.pdf 2>&1

Step 3b: If xelatex Fails - Capture Full Error and Retry with wkhtmltopdf

Before retrying, examine the full stderr output from Step 3a to understand the failure cause (missing engine, font issues, etc.). Then try wkhtmltopdf as fallback:

run_shell
command: pandoc /tmp/document_source_sanitized.md --pdf-engine=wkhtmltopdf -o output.pdf 2>&1

Step 4: Verify Outputs

Check that files were created successfully:

run_shell
command: ls -lh output.docx output.pdf output.html

Complete Example

# Generate Negotiation Strategy Document

## Step 1: Write Markdown source
write_file
path: /tmp/negotiation_strategy.md
content: |
  # Negotiation Strategy
  
  ## Executive Summary
  [Content with original unicode...]
  
  ## Resolution Path
  [Content...]
  
  ## BATNA Analysis
  [Content...]

## Step 2: Create sanitized version for PDF
write_file
path: /tmp/negotiation_strategy_sanitized.md
content: |
  # Negotiation Strategy
  
  ## Executive Summary
  [Content with unicode replaced: em-dash -> --, curly quotes -> straight, etc.]
  
  ## Resolution Path
  [Content...]
  
  ## BATNA Analysis
  [Content...]

## Step 3: Convert to DOCX (from original)
run_shell
command: pandoc /tmp/negotiation_strategy.md -o negotiation_strategy.docx

## Step 4: Convert to HTML (from original)
run_shell
command: pandoc /tmp/negotiation_strategy.md -o negotiation_strategy.html

## Step 5: Convert to PDF (try xelatex first, capture stderr)
run_shell
command: pandoc /tmp/negotiation_strategy_sanitized.md --pdf-engine=xelatex -o negotiation_strategy.pdf 2>&1

## Step 6: If xelatex fails, retry with wkhtmltopdf (after examining error)
run_shell
command: pandoc /tmp/negotiation_strategy_sanitized.md --pdf-engine=wkhtmltopdf -o negotiation_strategy.pdf 2>&1

## Step 7: Verify
run_shell
command: ls -lh negotiation_strategy.*

Advantages Over shell_agent

Common pandoc Commands

# Markdown to Word
pandoc input.md -o output.docx

# Markdown to PDF with xelatex (better Unicode support - TRY FIRST)
pandoc input.md -o output.pdf --pdf-engine=xelatex

# Markdown to PDF with wkhtmltopdf (fallback if xelatex unavailable)
pandoc input.md -o output.pdf --pdf-engine=wkhtmltopdf

# Markdown to HTML
pandoc input.md -o output.html

# With custom template
pandoc input.md --template=template.html -o output.html

# With metadata
pandoc input.md -o output.pdf --metadata title="Document Title"

Troubleshooting

• PDF generation fails with encoding error:

  • Use the sanitized markdown file (Step 2)
  • Try xelatex first (better Unicode support, more common in containers): --pdf-engine=xelatex
  • Capture full stderr with 2>&1 and examine the error before retrying
  • Then retry with wkhtmltopdf as fallback: --pdf-engine=wkhtmltopdf

• PDF generation fails: LaTeX not found:

  • Install LaTeX: apt-get install texlive-latex-recommended texlive-fonts-recommended
  • Preferred: Use --pdf-engine=xelatex (often pre-installed in containers)
  • Fallback: Use --pdf-engine=wkhtmltopdf if xelatex unavailable

• xelatex not found: Install with apt-get install texlive-xetex or use wkhtmltopdf fallback

• wkhtmltopdf not found: Install with apt-get install wkhtmltopdf

• DOCX formatting issues: Add --reference-doc=template.docx for custom styles

• Unicode/encoding errors in any format:

  • Add -f markdown+utf8 to pandoc command
  • Ensure source file is UTF-8 encoded: file -i source.md

• Special characters not rendering in PDF:

  • Use the character replacement table above
  • Create sanitized version before PDF conversion
  • Use xelatex engine for better Unicode font support

• Missing pandoc: Install via apt-get install pandoc or brew install pandoc

• Engine failures not diagnosed: Always append 2>&1 to capture stderr, examine output before retrying with different engine

Unicode Sanitization Script (Optional)

For repeated use, create a reusable sanitization script:

#!/bin/bash
# sanitize_for_pdf.sh - Replace problematic unicode chars for LaTeX/PDF
if [ -z "$1" ]; then
  echo "Usage: $0 <input.md> [output.md]"
  exit 1
fi
INPUT="$1"
OUTPUT="${2:-${1%.md}_sanitized.md}"

sed -e 's/—/--/g' \
    -e 's/–/-/g' \
    -e 's/"([^"]*)"/"\1"/g' \
    -e 's/'([^']*)/'\1'/g' \
    -e 's/…/.../g' \
    -e 's/→/->/g' \
    -e 's/←/<-/g' \
    -e 's/✓/[x]/g' \
    -e 's/✗/[ ]/g' \
    -e 's/©/(c)/g' \
    -e 's/®/(r)/g' \
    -e 's/™/(tm)/g' \
    "$INPUT" > "$OUTPUT"

echo "Sanitized: $INPUT -> $OUTPUT"

Save as sanitize_for_pdf.sh, make executable with chmod +x sanitize_for_pdf.sh, then use:

run_shell
command: ./sanitize_for_pdf.sh /tmp/document_source.md /tmp/document_source_sanitized.md

When to Return to shell_agent

After successfully completing the manual workflow once, you can attempt shell_agent again for similar tasks, now with a known-working fallback if errors recur. For documents with heavy Unicode content, consider always using the manual workflow with sanitization.

Related Skills

• document-gen-fallback: Original fallback workflow without Unicode guidance
• Use this skill when your documents contain special characters, symbols, or non-ASCII text that may cause LaTeX/PDF conversion issues Return to shell_agent in these scenarios:

1. Environment diagnostics fail - If pandoc or PDF engines are unavailable and installation isn't possible
2. Multiple tools returning 'unknown error' - Suggests broader environment issue; shell_agent may have different access
3. After successful manual completion - For similar future tasks, try shell_agent first with this workflow as fallback
4. Simple documents - For straightforward documents without complex Unicode, shell_agent is often sufficient
5. Time-sensitive tasks - When you need quick results and can accept some formatting uncertainty

For documents with heavy Unicode content, consider always using the manual workflow with sanitization, but only after confirming the toolchain is available.