Document Comparison

When to Use

Use this skill when:

• The user uploads two versions of the same document
• The user says /compare
• The user asks "what changed", "what's different", or "show me the differences"
• The user asks for a redline or tracked-changes document
• The user received a counterparty markup and wants to understand the changes

Process

1. Identify the two documents — ask the user which is the original and which is the revised version if not clear
2. Read both documents via read_document
3. Run compare with both document paths or texts — this returns a structured diff, similarity percentage, and visual output
4. Analyze the differences:

• What was added, removed, or modified?
• Which changes are substantive vs. editorial?
• Are any changes risky or favorable?
• Do changes align with playbook positions (if available in context)?

1. Present findings with a summary of key changes
2. If user wants a Word redline — call run_code (default Python) to generate a DOCX with tracked changes. Open the original with python-docx, compute a diff against the revised text, and insert w:ins/w:del tracked-change markup via lxml. See /docx-editing skill for OOXML tracked change patterns. Verify the output with structural checks.

Output Format

• Summary: Overall similarity %, number of changes, nature of changes (substantive vs. editorial)
• Key Changes: List of the most significant changes with assessment:
• What changed
• Why it matters (risk/benefit)
• Recommendation (accept / reject / negotiate)
• Full Change List: All detected changes in order
• Action Items: What to do next (accept, push back, request clarification)

Guidelines

• Always present the original vs. revised framing clearly
• Distinguish substantive changes (liability caps, notice periods, governing law) from editorial changes (formatting, numbering, defined terms)
• Prioritize substantive changes in the summary
• If playbook is available, flag changes that deviate from firm positions
• When producing a DOCX redline, confirm which direction the user wants (their changes tracked, or counterparty changes tracked)