Claude's Hidden Superpower: Extract Skills from Claude.ai and Unleash Them in Claude Code - GritFlow Blog

I just discovered something that changes how I think about AI-powered workflows.

Claude.ai (the web/desktop app) has built-in "skills" for creating and editing Word documents, Excel spreadsheets, PowerPoints, and PDFs. These skills can programmatically add track changes, insert comments, manipulate formulas—real professional document work without opening Microsoft Office.

Here's what most people don't realize: these skills are just markdown files and Python scripts. And you can extract them and use them in Claude Code.

Why does this matter? Because Claude Code runs locally in your terminal with full access to your file system, git repos, and toolchain.

Same brain. Way more power.

The Limitation of Claude.ai

When you use Claude.ai to create a redlined contract, here's what happens:

You upload a file
Claude works in an isolated container
You download the result

It works. But it's manual. One file at a time. No integration with your existing workflows.

What Changes with Claude Code + Skills

Now imagine this prompt in Claude Code:

In the /contracts folder, find all vendor agreements.
Update the payment terms from Net 30 to Net 45.
Add track changes so legal can review.
Save redlined versions to /contracts/Q1-updates/
Git commit with message "Updated payment terms for Q1 review"

Claude Code reads the skill documentation, understands that a .docx is just a ZIP of XML files, unpacks it, edits the XML with proper <w:ins> and <w:del> tags for track changes, repacks it, and moves on to the next file.

Fifty contracts. One command. Real track changes that open perfectly in Word.

How to Set This Up

Step 1: Get the skills from Claude.ai

Ask Claude in the web app to zip up the skills:

Zip up /mnt/skills/public/docx and give me the download

Do the same for xlsx, pptx, and pdf if you want those.

Step 2: Add to your project

Unzip into your repo or a shared location:

~/claude-skills/
  docx/
  xlsx/
  pptx/
  pdf/

Step 3: Tell Claude Code about them

Add to your CLAUDE.md:

## Document Skills

For Word documents, read ~/claude-skills/docx/SKILL.md first.
For Excel, read ~/claude-skills/xlsx/SKILL.md first.
For PowerPoint, read ~/claude-skills/pptx/SKILL.md first.
For PDFs, read ~/claude-skills/pdf/SKILL.md first.

That's it. Claude Code now has the same document capabilities as the web app, but running locally with full system access.

What's Actually in These Skills?

The docx skill, for example, contains:

File	Purpose
SKILL.md	Decision tree for which workflow to use
ooxml.md	600 lines of documentation on editing Word XML with track changes
docx-js.md	How to create new documents from scratch
Python scripts	Unpack/repack .docx files, document manipulation library
XML templates	For comments, tracked changes metadata

It's not magic. It's extremely well-documented procedures that tell Claude exactly how to manipulate Office Open XML format correctly.

Real Use Cases

<Cards> <Card title="Legal Teams" icon="scale"> Batch redline contract amendments across hundreds of documents with consistent track changes. </Card> <Card title="Finance" icon="chart-line"> Generate board decks by pulling data into PowerPoint templates, formatted correctly every time. </Card> <Card title="Operations" icon="clipboard-check"> Update SOPs across multiple Word documents, tracking every change for compliance. </Card> <Card title="Sales" icon="handshake"> Personalize proposal documents at scale while maintaining formatting. </Card> </Cards>

The Power of Local Execution

Here's what you can do with Claude Code that you can't do in the web app:

// Example: Batch process all contracts in a folder
const contracts = await glob('contracts/**/*.docx');

for (const contract of contracts) {
  // Claude Code has full filesystem access
  await processContract(contract, {
    updatePaymentTerms: 'Net 45',
    addTrackChanges: true,
    outputDir: 'contracts/Q1-updates/'
  });
}

// Commit all changes
await exec('git add . && git commit -m "Updated payment terms for Q1"');

The web app is sandboxed. Claude Code is integrated.

Why This Matters Beyond Documents

This pattern—extracting skills from Claude.ai and deploying them in Claude Code—works for any capability that's primarily "knowledge + procedure."

<Callout type="info" title="The Core Insight"> The web app is a sandbox. Claude Code is the production environment. </Callout>

Skills are portable expertise. Once you have them locally, you can:

✅ Version control them — Track changes to skill files in git
✅ Customize them — Adapt for your domain-specific needs
✅ Share them — Distribute across your team
✅ Chain them — Combine with other automations
✅ Run in CI/CD — Automate document processing pipelines

Integrating with GritFlow

This is where Grit Buckets become powerful. Create a bucket for document processing:

const docProcessingBucket = createGritBucket({
  name: 'Contract Processing',
  category: 'legal',
  goals: [
    'Batch update payment terms',
    'Add compliance language',
    'Generate redlined versions'
  ],
  skills: ['docx', 'pdf']
});

// GritFlow orchestrates the workflow
gritFlow.flowInto(docProcessingBucket);

Your prompts, your skills, your automation—all organized in one bucket. Never lose context. Never repeat yourself.

The Bigger Picture

Anthropic has a plugin marketplace for Claude Code, but it's mostly MCP integrations (Notion, Atlassian, etc.) right now. The document skills aren't there yet.

But they exist. They're sitting in Claude.ai's environment at /mnt/skills/public/. And there's nothing stopping you from using them today.

<Callout type="warning" title="The Gap"> The gap between "AI demo" and "AI in production" is often just knowing where the pieces are and how to connect them. </Callout>

Now you know.

Quick Start Commands

Get the skills right now:

# In Claude.ai web app, ask:
"Zip up /mnt/skills/public/docx and give me the download"
"Zip up /mnt/skills/public/xlsx and give me the download"
"Zip up /mnt/skills/public/pptx and give me the download"
"Zip up /mnt/skills/public/pdf and give me the download"

Then set up your CLAUDE.md and start automating.

What's Next?

In future posts, we'll cover:

Deep dive into each skill — Exactly what's possible with Word, Excel, PowerPoint, and PDF manipulation
Building custom skills — Create your own domain-specific skills
Skill chaining — Combine multiple skills for complex workflows
CI/CD integration — Run document automation in your pipelines

Want the skill files? Ask Claude.ai to zip up /mnt/skills/public/docx (or xlsx, pptx, pdf) and it'll give you a download link.

<Callout type="tip" title="Pro Tip"> Create a `~/claude-skills/` directory and add it to your global `CLAUDE.md`. Every project will have access to document skills automatically. </Callout>