docx

name: docx description: "Use this skill whenever the user wants to create, read, edit, or manipulate Word documents (.docx files). Triggers include: any mention of "Word doc", "word document", ".docx", or requests to produce professional documents with formatting like tables of contents, headings, page numbers, or letterheads. Also use when extracting or reorganizing content from .docx files, inserting or replacing images in documents, performing find-and-replace in Word files, working with tracked changes or comments, or converting content into a polished Word document. If the user asks for a "report", "memo", "letter", "template", or similar deliverable as a Word or .docx file, use this skill. Do NOT use for PDFs, spreadsheets, or general coding tasks."

DOCX creation, editing, and analysis

Overview

A .docx file is a ZIP archive containing XML files.

Quick Reference

Converting .doc to .docx

Legacy .doc files must be converted before editing:

libreoffice --headless --convert-to docx document.doc

Reading Content

# Text extraction with tracked changes
pandoc --track-changes=all document.docx -o output.md

# Raw XML access - unzip the docx
mkdir -p unpacked && unzip -o document.docx -d unpacked/
# Main content is in unpacked/word/document.xml

Converting to Images

libreoffice --headless --convert-to pdf document.docx
pdftoppm -jpeg -r 150 document.pdf page

Accepting Tracked Changes

To produce a clean document with all tracked changes accepted (requires LibreOffice):

# Use a LibreOffice macro to accept all changes
libreoffice --headless --invisible --norestore \
  "macro:///Standard.Module1.AcceptAllChanges" input.docx

Or use pandoc to extract clean text (without change tracking markup):

pandoc --track-changes=accept document.docx -o clean.md

Creating New Documents

Generate .docx files with JavaScript using the docx npm package, then validate. Install: npm install -g docx

Setup

const { Document, Packer, Paragraph, TextRun, Table, TableRow, TableCell, ImageRun,
        Header, Footer, AlignmentType, PageOrientation, LevelFormat, ExternalHyperlink,
        TableOfContents, HeadingLevel, BorderStyle, WidthType, ShadingType,
        VerticalAlign, PageNumber, PageBreak } = require('docx');

const doc = new Document({ sections: [{ children: [/* content */] }] });
Packer.toBuffer(doc).then(buffer => fs.writeFileSync("doc.docx", buffer));

Page Size

// CRITICAL: docx-js defaults to A4, not US Letter
// Always set page size explicitly for consistent results
sections: [{
  properties: {
    page: {
      size: {
        width: 12240,   // 8.5 inches in DXA
        height: 15840   // 11 inches in DXA
      },
      margin: { top: 1440, right: 1440, bottom: 1440, left: 1440 } // 1 inch margins
    }
  },
  children: [/* content */]
}]

Common page sizes (DXA units, 1440 DXA = 1 inch):

Landscape orientation: docx-js swaps width/height internally, so pass portrait dimensions and let it handle the swap:

size: {
  width: 12240,   // Pass SHORT edge as width
  height: 15840,  // Pass LONG edge as height
  orientation: PageOrientation.LANDSCAPE  // docx-js swaps them in the XML
},

Styles (Override Built-in Headings)

Use Arial as the default font (universally supported). Keep titles black for readability.

const doc = new Document({
  styles: {
    default: { document: { run: { font: "Arial", size: 24 } } }, // 12pt default
    paragraphStyles: [
      // IMPORTANT: Use exact IDs to override built-in styles
      { id: "Heading1", name: "Heading 1", basedOn: "Normal", next: "Normal", quickFormat: true,
        run: { size: 32, bold: true, font: "Arial" },
        paragraph: { spacing: { before: 240, after: 240 }, outlineLevel: 0 } },
      { id: "Heading2", name: "Heading 2", basedOn: "Normal", next: "Normal", quickFormat: true,
        run: { size: 28, bold: true, font: "Arial" },
        paragraph: { spacing: { before: 180, after: 180 }, outlineLevel: 1 } },
    ]
  },
  sections: [{
    children: [
      new Paragraph({ heading: HeadingLevel.HEADING_1, children: [new TextRun("Title")] }),
    ]
  }]
});

Lists (NEVER use unicode bullets)

// WRONG - never manually insert bullet characters
new Paragraph({ children: [new TextRun("* Item")] })  // BAD

// CORRECT - use numbering config with LevelFormat.BULLET
const doc = new Document({
  numbering: {
    config: [
      { reference: "bullets",
        levels: [{ level: 0, format: LevelFormat.BULLET, text: "\u2022", alignment: AlignmentType.LEFT,
          style: { paragraph: { indent: { left: 720, hanging: 360 } } } }] },
      { reference: "numbers",
        levels: [{ level: 0, format: LevelFormat.DECIMAL, text: "%1.", alignment: AlignmentType.LEFT,
          style: { paragraph: { indent: { left: 720, hanging: 360 } } } }] },
    ]
  },
  sections: [{
    children: [
      new Paragraph({ numbering: { reference: "bullets", level: 0 },
        children: [new TextRun("Bullet item")] }),
      new Paragraph({ numbering: { reference: "numbers", level: 0 },
        children: [new TextRun("Numbered item")] }),
    ]
  }]
});

Tables

CRITICAL: Tables need dual widths - set both columnWidths on the table AND width on each cell.

const border = { style: BorderStyle.SINGLE, size: 1, color: "CCCCCC" };
const borders = { top: border, bottom: border, left: border, right: border };

new Table({
  width: { size: 9360, type: WidthType.DXA },
  columnWidths: [4680, 4680],
  rows: [
    new TableRow({
      children: [
        new TableCell({
          borders,
          width: { size: 4680, type: WidthType.DXA },
          shading: { fill: "D5E8F0", type: ShadingType.CLEAR }, // CLEAR not SOLID
          margins: { top: 80, bottom: 80, left: 120, right: 120 },
          children: [new Paragraph({ children: [new TextRun("Cell")] })]
        })
      ]
    })
  ]
})

Images

// CRITICAL: type parameter is REQUIRED
new Paragraph({
  children: [new ImageRun({
    type: "png",
    data: fs.readFileSync("image.png"),
    transformation: { width: 200, height: 150 },
    altText: { title: "Title", description: "Desc", name: "Name" }
  })]
})

Page Breaks

new Paragraph({ children: [new PageBreak()] })
// Or use pageBreakBefore
new Paragraph({ pageBreakBefore: true, children: [new TextRun("New page")] })

Table of Contents

// CRITICAL: Headings must use HeadingLevel ONLY - no custom styles
new TableOfContents("Table of Contents", { hyperlink: true, headingStyleRange: "1-3" })

Headers/Footers

sections: [{
  properties: {
    page: { margin: { top: 1440, right: 1440, bottom: 1440, left: 1440 } }
  },
  headers: {
    default: new Header({ children: [new Paragraph({ children: [new TextRun("Header")] })] })
  },
  footers: {
    default: new Footer({ children: [new Paragraph({
      children: [new TextRun("Page "), new TextRun({ children: [PageNumber.CURRENT] })]
    })] })
  },
  children: [/* content */]
}]

Critical Rules for docx-js

• Set page size explicitly - defaults to A4; use US Letter (12240 x 15840 DXA) for US documents
• Never use \n - use separate Paragraph elements
• Never use unicode bullets - use LevelFormat.BULLET with numbering config
• PageBreak must be in Paragraph - standalone creates invalid XML
• ImageRun requires type - always specify png/jpg/etc
• Always set table width with DXA - never use WidthType.PERCENTAGE (breaks in Google Docs)
• Tables need dual widths - columnWidths array AND cell width, both must match
• Use ShadingType.CLEAR - never SOLID for table shading
• TOC requires HeadingLevel only - no custom styles on heading paragraphs
• Override built-in styles - use exact IDs: "Heading1", "Heading2", etc.
• Include outlineLevel - required for TOC (0 for H1, 1 for H2, etc.)

Editing Existing Documents

Follow all 3 steps in order.

Step 1: Unpack

Since .docx is a ZIP archive, unpack it to access the XML:

mkdir -p unpacked
unzip -o document.docx -d unpacked/

# Pretty-print the main document XML for easier editing
python3 -c "
import xml.dom.minidom, sys
doc = xml.dom.minidom.parse('unpacked/word/document.xml')
with open('unpacked/word/document.xml', 'w') as f:
    f.write(doc.toprettyxml(indent='  '))
"

Step 2: Edit XML

Edit files in unpacked/word/. See XML Reference below for patterns.

Use "Claude" as the author for tracked changes and comments, unless the user explicitly requests a different name.

Use the edit_file tool directly for string replacement. Do not write Python scripts. Scripts introduce unnecessary complexity. The edit_file tool shows exactly what is being replaced.

CRITICAL: Use smart quotes for new content. When adding text with apostrophes or quotes, use XML entities:

<w:t>Here&#x2019;s a quote: &#x201C;Hello&#x201D;</w:t>

Adding comments: Edit the XML directly in unpacked/word/comments.xml to add comment entries, then add markers to document.xml (see Comments in XML Reference below).

Step 3: Repack

Repack the directory into a .docx file:

cd unpacked && zip -r ../output.docx . -x ".*" && cd ..

Optionally validate with LibreOffice by opening the result:

libreoffice --calc output.docx

Common Pitfalls

• Replace entire <w:r> elements: When adding tracked changes, replace the whole <w:r>...</w:r> block with <w:del>...<w:ins>... as siblings
• Preserve <w:rPr> formatting: Copy the original run's <w:rPr> block into your tracked change runs

XML Reference

Schema Compliance

• Element order in <w:pPr>: <w:pStyle>, <w:numPr>, <w:spacing>, <w:ind>, <w:jc>, <w:rPr> last
• Whitespace: Add xml:space="preserve" to <w:t> with leading/trailing spaces
• RSIDs: Must be 8-digit hex (e.g., 00AB1234)

Tracked Changes

Insertion:

<w:ins w:id="1" w:author="Claude" w:date="2025-01-01T00:00:00Z">
  <w:r><w:t>inserted text</w:t></w:r>
</w:ins>

Deletion:

<w:del w:id="2" w:author="Claude" w:date="2025-01-01T00:00:00Z">
  <w:r><w:delText>deleted text</w:delText></w:r>
</w:del>

Inside <w:del>: Use <w:delText> instead of <w:t>, and <w:delInstrText> instead of <w:instrText>.

Minimal edits - only mark what changes:

<w:r><w:t>The term is </w:t></w:r>
<w:del w:id="1" w:author="Claude" w:date="...">
  <w:r><w:delText>30</w:delText></w:r>
</w:del>
<w:ins w:id="2" w:author="Claude" w:date="...">
  <w:r><w:t>60</w:t></w:r>
</w:ins>
<w:r><w:t> days.</w:t></w:r>

Deleting entire paragraphs - also mark the paragraph mark as deleted:

<w:p>
  <w:pPr>
    <w:rPr>
      <w:del w:id="1" w:author="Claude" w:date="2025-01-01T00:00:00Z"/>
    </w:rPr>
  </w:pPr>
  <w:del w:id="2" w:author="Claude" w:date="2025-01-01T00:00:00Z">
    <w:r><w:delText>Entire paragraph content being deleted...</w:delText></w:r>
  </w:del>
</w:p>

Rejecting another author's insertion:

<w:ins w:author="Jane" w:id="5">
  <w:del w:author="Claude" w:id="10">
    <w:r><w:delText>their inserted text</w:delText></w:r>
  </w:del>
</w:ins>

Restoring another author's deletion:

<w:del w:author="Jane" w:id="5">
  <w:r><w:delText>deleted text</w:delText></w:r>
</w:del>
<w:ins w:author="Claude" w:id="10">
  <w:r><w:t>deleted text</w:t></w:r>
</w:ins>

Comments

Add comment entries to unpacked/word/comments.xml:

<w:comment w:id="0" w:author="Claude" w:date="2025-01-01T00:00:00Z" w:initials="C">
  <w:p>
    <w:r><w:t>Comment text here</w:t></w:r>
  </w:p>
</w:comment>

Then add markers to document.xml:

<w:commentRangeStart w:id="0"/>
<w:r><w:t>commented text</w:t></w:r>
<w:commentRangeEnd w:id="0"/>
<w:r><w:rPr><w:rStyle w:val="CommentReference"/></w:rPr><w:commentReference w:id="0"/></w:r>

CRITICAL: <w:commentRangeStart> and <w:commentRangeEnd> are siblings of <w:r>, never inside <w:r>.

Images

1. Add image file to unpacked/word/media/
2. Add relationship to unpacked/word/_rels/document.xml.rels:

<Relationship Id="rId5" Type=".../image" Target="media/image1.png"/>

3. Add content type to unpacked/[Content_Types].xml:

<Default Extension="png" ContentType="image/png"/>

4. Reference in document.xml:

<w:drawing>
  <wp:inline>
    <wp:extent cx="914400" cy="914400"/>  <!-- EMUs: 914400 = 1 inch -->
    <a:graphic>
      <a:graphicData uri=".../picture">
        <pic:pic>
          <pic:blipFill><a:blip r:embed="rId5"/></pic:blipFill>
        </pic:pic>
      </a:graphicData>
    </a:graphic>
  </wp:inline>
</w:drawing>

Dependencies

Install as needed:

• pandoc - text extraction and format conversion
• docx npm package - npm install -g docx (creating new documents)
• LibreOffice - PDF conversion, .doc to .docx conversion (brew install --cask libreoffice)
• Poppler - pdftoppm for converting to images (brew install poppler)