DOCX Template Filling - Forensic Preservation

DOCX Template Filling - Forensic Preservation

Fill template forms programmatically with zero detectable artifacts. The filled document must be indistinguishable from manual typing in the original template.

When to Use This Skill

Invoke when:

• Filling standardized forms and templates
• Completing application forms
• Responding to questionnaires and surveys
• Processing template-based documents
• Any scenario where the recipient must not detect programmatic manipulation

Critical requirement: Template integrity must be 100% preserved (logos, footers, headers, styles, metadata, element structure).

Core Philosophy: Preservation Over Recreation

WRONG approach: Extract content from template, generate new document

• Loses metadata
• Changes element IDs
• Alters styles subtly
• Creates detectable artifacts

RIGHT approach: Load template, insert content at anchor points using XML API

• Preserves all original elements
• Maintains metadata
• Zero structural changes
• Indistinguishable from manual entry

Critical Anti-Patterns

❌ NEVER: Use pandoc with --reference-doc

# This SEEMS correct but ONLY copies styles, NOT structure
pandoc content.md -o output.docx --reference-doc=template.docx

What happens:

• Template's tables disappear
• Logos, headers, footers lost
• Only style definitions copied
• Looks completely different

Why it fails: --reference-doc means "copy the style definitions," NOT "preserve the document structure"

❌ NEVER: Append content at the end

# This destroys template structure
template = Document('template.docx')

# Remove content after markers
# ... (deletion logic)

# Append all new content at end
for para in new_content:
    template.add_paragraph(para.text)  # WRONG!

What happens:

• Template questions appear unanswered
• All answers grouped at end
• Structure broken
• Obviously programmatic

❌ NEVER: Recreate tables

# DON'T copy table structure and rebuild
new_table = template.add_table(rows=3, cols=2)
# Even if copying all properties, it's not the original!

What happens:

• Loses original element IDs
• Style inheritance breaks
• Metadata changes
• Detectable as modified

Essential Workflow

Step 1: Inspect Template Structure FIRST

Always inspect before modifying. Never assume structure.

Use the provided inspection script:

python scripts/​inspect_template.py template.docx

This prints:

• All tables with identities
• Potential anchor points (paragraphs ending with ":", "Answer:", etc.)
• Headers and footers
• Document element counts

Why critical: Prevents modifying wrong tables, missing anchors, breaking structure.

Step 2: Selective Table Filling

Modify cells in place. Never recreate tables.

from docx import Document

template = Document('template.docx')

# Fill specific cells in existing table
info_table = template.tables[0]
info_table.rows[0].cells[1].text = "Jane Smith"
info_table.rows[1].cells[1].text = "S12345"

# Table structure, styles, borders all preserved

Principle: Modify existing cells. Never remove and recreate.

Step 3: Anchor-Based Content Insertion

Insert content at specific positions using XML API.

# Find anchor paragraphs
anchor_positions = []
for i, para in enumerate(template.paragraphs):
    if para.text.strip() == "Answer:":
        anchor_positions.append(i)

# Insert content after anchor using XML API
def insert_after(doc, anchor_idx, content_paras):
    anchor_elem = doc.paragraphs[anchor_idx]._element
    parent = anchor_elem.getparent()

    for offset, para in enumerate(content_paras):
        parent.insert(
            parent.index(anchor_elem) + 1 + offset,
            para._element
        )

# Load content to insert
content_doc = Document('my_content.docx')
section_paragraphs = content_doc.paragraphs[5:64]

# Insert at anchor
insert_after(template, anchor_positions[0], section_paragraphs)

# Save
template.save('completed.docx')

Why XML API:

• doc.add_paragraph() appends at end → wrong position
• para.insert_paragraph_before() has stale reference issues
• XML API: direct element manipulation → correct position, zero artifacts

Step 4: Multi-Anchor Insertion (Reverse Order)

When inserting at multiple positions, insert from bottom to top to preserve earlier indices.

# Template has anchors at paragraphs 18, 27, 37

# Insert in REVERSE order
insert_after(template, 37, section3_content)  # Last anchor first
insert_after(template, 27, section2_content)  # Middle still at 27
insert_after(template, 18, section1_content)  # First still at 18

Why reverse: Inserting content shifts later paragraph indices but not earlier ones.

Advanced Patterns

For detailed implementations, see references/​patterns.md:

• Content range extraction - Extract multi-section content between markers
• Table identity detection - Identify tables when no IDs exist
• Robust anchor matching - exact/​partial/​smart modes
• Table repositioning - Move tables without recreating
• Verification - Ensure zero artifacts after filling

Common Scenarios

Scenario 1: Form with Info Table + Q&A

template = Document('form_template.docx')

# Fill info table
info_table = template.tables[0]
info_table.rows[0].cells[1].text = "Applicant Name"

# Find "Answer:" anchors
anchors = [i for i, p in enumerate(template.paragraphs)
           if p.text.strip() == "Answer:"]

# Insert responses
responses = Document('my_responses.docx')
response_content = responses.paragraphs[5:30]

insert_after(template, anchors[0], response_content)

template.save('form_completed.docx')

Scenario 2: Report with Table Repositioning

template = Document('report_template.docx')

# Fill team table
team_table = template.tables[0]
team_table.rows[0].cells[1].text = "Team 5"

# Insert section content at anchors
# ... (insertion code)

# Move summary table to correct position
summary_heading_idx = next(i for i, p in enumerate(template.paragraphs)
                           if "Summary Table:" in p.text)

# Move table from end to after summary heading
# See references/​patterns.md for move_table_to_position()

template.save('report_completed.docx')

Bundled Resources

Scripts

• scripts/​inspect_template.py - Inspect template structure before modification
  • Usage: python scripts/​inspect_template.py <template.docx>
  • Prevents destructive mistakes by showing all tables, anchors, headers/​footers

References

• references/​patterns.md - Detailed technical patterns
  • Content range extraction
  • Table identity detection strategies
  • XML-level insertion patterns
  • Multi-anchor workflows
  • Verification procedures
  • Complete code examples

Load patterns.md when implementing specific operations beyond basic workflow.

Verification Checklist

Template filling is successful if:

• Filled document indistinguishable from manual entry
• All template tables preserved (count unchanged unless expected)
• Headers/​footers unchanged
• Logo(s) intact
• Scoring/​grading tables empty (if they should be)
• Styles identical to original
• Content inserted at correct anchor points (not at end)
• Template owner cannot detect programmatic manipulation

Key Lessons

This skill documents patterns where:

• Templates have info tables (to fill) and evaluation/​scoring tables (preserve empty)
• Multiple anchor points like "Answer:", "Response:", or "Solution:" for content insertion
• Tables may need repositioning to correct sections
• Document structure must remain intact (headers, footers, logos, branding)
• Zero artifacts requirement (recipient cannot detect automation)

Use cases: Forms, questionnaires, standardized documents, applications, reports.

Core principle: Preservation over recreation. Never rebuild - always modify in place.