Summarizing and rewriting text

Introduction to Claude Models

Nikhil Rangarajan

Data Scientist

Summarization tasks

Summarizing long reports

A page representing a summarized doc

Summarization tasks

Summarizing long reports
Rewriting technical docs

A page representing a summarized doc, and a window open on an API coding repository

Summarization tasks

Summarizing long reports
Rewriting technical docs
Changing from formal to friendly tone

Maintains meaning while changing format

A page representing a summarized doc, a window open on an API coding repository, and a person reading a formal doc

Summarization techniques

Specific prompt
Length control: Specify word count or paragraph limits
Focus points

# Summarization prompt
prompt = """Please summarize the 
following text in 2-3 sentences:
{project_report}. Focus on project 
updates."""

response = client.messages.create(
    model="claude-sonnet-4-20250514",
    messages=[{"role": "user", 
               "content": prompt}]
)

Rewriting with system messages

System messages control tone and style globally
Tone options: Professional, casual, technical, friendly
Consistency: System message applies to entire conversation

messages=[{"role": "user", 
               "content": prompt}]

system_message = """You are a 
professional editor who rewrites 
content in a clear, engaging style."""

messages = [
    {"role": "system", 
     "content": system_message},
    {"role": "user", 
     "content": "Rewrite: [content]"}]

Managing output length with max_tokens

max_tokens sets a specific response length
~4 characters per token
150 tokens = 600 characters = 1 paragraph

# Controlling output length
response = client.messages.create(
    model="claude-sonnet-4-20250514",
      # Approximately 600 characters
    max_tokens=150,  
    messages=[{
        "role": "user", 
        "content": "Summarize this 
             quarterly report: [text]"
    }])

Key takeaways

📌 Summaries: long key points
📝 Rewrites: adjust tone
🔎 Be explicit on format
🔧 Tune max_tokens
✅ Verify meaning

Let's practice!

Introduction to Claude Models