Claude Skills Cookbook 🚀

A comprehensive guide to using Claude's Skills feature for document generation, data analysis, and business automation. This cookbook demonstrates how to leverage Claude's built-in skills for Excel, PowerPoint, and PDF creation, as well as how to build custom skills for specialized workflows.

🎯 See Skills in Action: Check out Claude Creates Files to see how these Skills power Claude's ability to create and edit documents directly in Claude.ai and the desktop app!

What are Skills?

Skills are organized packages of instructions, executable code, and resources that give Claude specialized capabilities for specific tasks. Think of them as "expertise packages" that Claude can discover and load dynamically to:

Create professional documents (Excel, PowerPoint, PDF, Word)
Perform complex data analysis and visualization
Apply company-specific workflows and branding
Automate business processes with domain expertise

📖 Read our engineering blog post on Equipping agents for the real world with Skills

Key Features

✨ Progressive Disclosure Architecture - Skills load only when needed, optimizing token usage
📊 Financial Focus - Real-world examples for finance and business analytics
🔧 Custom Skills Development - Learn to build and deploy your own skills
🎯 Production-Ready Examples - Code you can adapt for immediate use

Cookbook Structure

📚 Notebook 1: Introduction to Skills

Learn the fundamentals of Claude's Skills feature with quick-start examples.

Understanding Skills architecture
Setting up the API with beta headers
Creating your first Excel spreadsheet
Generating PowerPoint presentations
Exporting to PDF format

💼 Notebook 2: Financial Applications

Explore powerful business use cases with real financial data.

Building financial dashboards with charts and pivot tables
Portfolio analysis and investment reporting
Cross-format workflows: CSV → Excel → PowerPoint → PDF
Token optimization strategies

🔧 Notebook 3: Custom Skills Development

Master the art of creating your own specialized skills.

Building a financial ratio calculator
Creating company brand guidelines skill
Advanced: Financial modeling suite
Best practices and security considerations

Quick Start

Prerequisites

Python 3.8 or higher
Anthropic API key (get one here)
Jupyter Notebook or JupyterLab

Installation

bash

git clone https://github.com/anthropics/claude-cookbooks.git
cd claude-cookbooks/skills

Create virtual environment (recommended)

bash

python -m venv venv
source venv/bin/activate  # On Windows: venv\Scripts\activate

Install dependencies

bash

pip install -r requirements.txt

Configure API key

bash

cp .env.example .env
# Edit .env and add your ANTHROPIC_API_KEY

Launch Jupyter

bash

jupyter notebook

Start with Notebook 1 Open notebooks/01_skills_introduction.ipynb and follow along!

Sample Data

The cookbook includes realistic financial datasets in sample_data/:

📊 financial_statements.csv - Quarterly P&L, balance sheet, and cash flow data
💰 portfolio_holdings.json - Investment portfolio with performance metrics
📋 budget_template.csv - Department budget with variance analysis
📈 quarterly_metrics.json - KPIs and operational metrics

Project Structure

skills/
├── notebooks/                    # Jupyter notebooks
│   ├── 01_skills_introduction.ipynb
│   ├── 02_skills_financial_applications.ipynb
│   └── 03_skills_custom_development.ipynb
├── sample_data/                  # Financial datasets
│   ├── financial_statements.csv
│   ├── portfolio_holdings.json
│   ├── budget_template.csv
│   └── quarterly_metrics.json
├── custom_skills/                # Your custom skills
│   ├── financial_analyzer/
│   ├── brand_guidelines/
│   └── report_generator/
├── outputs/                      # Generated files
├── docs/                         # Documentation
├── requirements.txt             # Python dependencies
├── .env.example                 # Environment template
└── README.md                    # This file

API Configuration

Skills require specific beta headers. The notebooks handle this automatically, but here's what's happening behind the scenes:

python

from anthropic import Anthropic

client = Anthropic(
    api_key="your-api-key",
    default_headers={
        "anthropic-beta": "code-execution-2025-08-25,files-api-2025-04-14,skills-2025-10-02"
    }
)

Required Beta Headers:

code-execution-2025-08-25 - Enables code execution for Skills
files-api-2025-04-14 - Required for downloading generated files
skills-2025-10-02 - Enables Skills feature

Working with Generated Files

When Skills create documents (Excel, PowerPoint, PDF, etc.), they return file_id attributes in the response. You must use the Files API to download these files.

How It Works

Skills create files during code execution
Response includes file_ids for each created file
Use Files API to download the actual file content
Save locally or process as needed

Example: Creating and Downloading an Excel File

python

from anthropic import Anthropic

client = Anthropic(api_key="your-api-key")

# Step 1: Use a skill to create a file
response = client.messages.create(
    model="claude-sonnet-4-6",
    max_tokens=4096,
    container={
        "skills": [
            {"type": "anthropic", "skill_id": "xlsx", "version": "latest"}
        ]
    },
    tools=[{"type": "code_execution_20250825", "name": "code_execution"}],
    messages=[{
        "role": "user",
        "content": "Create an Excel file with a simple budget spreadsheet"
    }]
)

# Step 2: Extract file_id from the response
file_id = None
for block in response.content:
    if block.type == "tool_result" and hasattr(block, 'output'):
        # Look for file_id in the tool output
        if 'file_id' in str(block.output):
            file_id = extract_file_id(block.output)  # Parse the file_id
            break

# Step 3: Download the file using Files API
if file_id:
    file_content = client.beta.files.download(file_id=file_id)

    # Step 4: Save to disk
    with open("outputs/budget.xlsx", "wb") as f:
        f.write(file_content.read())

    print(f"✅ File downloaded: budget.xlsx")

Files API Methods

python

# Download file content (binary)
content = client.beta.files.download(file_id="file_abc123...")
with open("output.xlsx", "wb") as f:
    f.write(content.read())  # Use .read() not .content

# Get file metadata
info = client.beta.files.retrieve_metadata(file_id="file_abc123...")
print(f"Filename: {info.filename}, Size: {info.size_bytes} bytes")  # Use size_bytes not size

# List all files
files = client.beta.files.list()
for file in files.data:
    print(f"{file.filename} - {file.created_at}")

# Delete a file
client.beta.files.delete(file_id="file_abc123...")

Important Notes:

Files are stored temporarily on Anthropic's servers
Downloaded files should be saved to your local outputs/ directory
The Files API uses the same API key as the Messages API
All notebooks include helper functions for file download
Files are overwritten by default - rerunning cells will replace existing files (you'll see [overwritten] in the output)

See the Files API documentation for complete details.

Built-in Skills Reference

Claude comes with these pre-built skills:

Skill	ID	Description
Excel	`xlsx`	Create and manipulate Excel workbooks with formulas, charts, and formatting
PowerPoint	`pptx`	Generate professional presentations with slides, charts, and transitions
PDF	`pdf`	Create formatted PDF documents with text, tables, and images
Word	`docx`	Generate Word documents with rich formatting and structure

Creating Custom Skills

Custom skills follow this structure:

my_skill/
├── SKILL.md           # Required: Instructions for Claude
├── scripts/           # Optional: Python/JS code
│   └── processor.py
└── resources/         # Optional: Templates, data
    └── template.xlsx

Learn more in Notebook 3.

Common Use Cases

Financial Reporting

Automated quarterly reports
Budget variance analysis
Investment performance dashboards

Data Analysis

Excel-based analytics with complex formulas
Pivot table generation
Statistical analysis and visualization

Document Automation

Branded presentation generation
Report compilation from multiple sources
Cross-format document conversion

Performance Tips

Use Progressive Disclosure: Skills load in stages to minimize token usage
Batch Operations: Process multiple files in a single conversation
Skill Composition: Combine multiple skills for complex workflows
Cache Reuse: Use container IDs to reuse loaded skills

Troubleshooting

Common Issues

API Key Not Found

ValueError: ANTHROPIC_API_KEY not found

→ Make sure you've copied .env.example to .env and added your key

Skills Beta Header Missing

Error: Skills feature requires beta header

→ Ensure you're using the correct beta headers as shown in the notebooks

Token Limit Exceeded

Error: Request exceeds token limit

→ Break large operations into smaller chunks or use progressive disclosure

Resources

Classification with Claude

Content policy enforcement with Claude

data

ad_creatives

product_listings

ugc

Knowledge Graph Construction with Claude

Retrieval Augmented Generation with Claude

Summarization with Claude

Text-to-SQL with Claude

.claude

agents

commands

output-styles

output_reports

Hosting the research agent

CMA as an MCP server

sre

runbooks

Linear × Claude Managed Agents

Road trip planner: stream sessions, scope vault credentials, override models, and review plans agent-to-agent

Self-Hosted Sandboxes

文档

Sentry triage × Claude Managed Agents

Slack × Claude Managed Agents

Building Effective Agents Cookbook

prompts

analyzing-financial-statements

applying-brand-guidelines

creating-financial-models

Claude Skills Cookbook 🚀 ​

What are Skills? ​

Key Features ​

Cookbook Structure ​

📚 Notebook 1: Introduction to Skills ​

💼 Notebook 2: Financial Applications ​

🔧 Notebook 3: Custom Skills Development ​

Quick Start ​

Prerequisites ​

Installation ​

Sample Data ​

Project Structure ​

API Configuration ​

Working with Generated Files ​

How It Works ​

Example: Creating and Downloading an Excel File ​

Files API Methods ​

Built-in Skills Reference ​

Creating Custom Skills ​

Common Use Cases ​

Financial Reporting ​

Data Analysis ​

Document Automation ​

Performance Tips ​

Troubleshooting ​

Common Issues ​

Resources ​

Documentation ​

Support Articles ​

Community & Support ​

Claude Skills Cookbook 🚀

What are Skills?

Key Features

Cookbook Structure

📚 Notebook 1: Introduction to Skills

💼 Notebook 2: Financial Applications

🔧 Notebook 3: Custom Skills Development

Quick Start

Prerequisites

Installation

Sample Data

Project Structure

API Configuration

Working with Generated Files

How It Works

Example: Creating and Downloading an Excel File

Files API Methods

Built-in Skills Reference

Creating Custom Skills

Common Use Cases

Financial Reporting

Data Analysis

Document Automation

Performance Tips

Troubleshooting

Common Issues

Resources

Documentation

Support Articles

Community & Support