Meet the New Claude Opus 5: Frontier-Class Agentic Coding and Computer Use at Unchanged Opus Pricing

Introduction

In this tutorial, you'll learn how to interact with Claude Opus 5, the latest advanced AI model from Anthropic. Claude Opus 5 is designed for complex tasks like coding, computer use, and agentic workflows. This tutorial will guide you through setting up your environment and making your first API calls to Claude Opus 5, even though you won't be able to directly use the model without an API key. We'll focus on understanding the API structure and how to prepare your prompts for this powerful model.

Prerequisites

• A basic understanding of what APIs are and how they work
• Access to a computer with internet connection
• Basic programming knowledge (Python recommended)
• API key from Anthropic (you'll need to sign up for one)

Step-by-Step Instructions

Step 1: Set Up Your Development Environment

Before you can interact with Claude Opus 5, you'll need to install the required libraries. Open your terminal or command prompt and run the following command:

pip install anthropic

This installs the official Python client library for Anthropic's API, which will make it easier to send requests and receive responses from Claude Opus 5.

Step 2: Get Your Anthropic API Key

You'll need an API key from Anthropic to access Claude Opus 5. Visit the Anthropic Console and sign up for an account. Once you're logged in, navigate to the API section and generate a new API key. Keep this key secure and never share it publicly.

Step 3: Create Your Python Script

Create a new Python file (e.g., claude_opus_demo.py) and start by importing the required modules:

import os
from anthropic import Anthropic

Next, initialize the Anthropic client with your API key:

client = Anthropic(api_key=os.getenv("ANTHROPIC_API_KEY"))

Why do we use os.getenv? This approach keeps your API key secure by storing it in environment variables rather than hardcoding it into your script. This is a best practice for security.

Step 4: Set Up Environment Variables

To keep your API key secure, set it as an environment variable. On Linux/macOS, run:

export ANTHROPIC_API_KEY="your_actual_api_key_here"

On Windows, use:

set ANTHROPIC_API_KEY=your_actual_api_key_here

Replace your_actual_api_key_here with the key you generated in Step 2.

Step 5: Create a Basic Prompt for Claude Opus 5

Now, let's create a simple prompt that demonstrates Claude Opus 5's capabilities. We'll ask it to help with a coding task:

prompt = "\n\nHuman: You are Claude Opus 5. Please help me write a Python function that calculates the factorial of a number. Explain your thought process step-by-step.\n\nAssistant:"

Why are we using this specific format? Claude uses a specific prompt structure where you define the role of the AI (Human) and then specify the assistant's behavior (Assistant). This helps Claude understand how to respond.

Step 6: Send the Request to Claude Opus 5

Now, we'll send our prompt to Claude Opus 5 and receive a response:

response = client.messages.create(
    model="claude-3-opus-20260724",
    max_tokens=1000,
    messages=[
        {"role": "user", "content": prompt}
    ]
)

print(response.content[0].text)

This code sends your prompt to Claude Opus 5 and prints the response. The model will return a detailed explanation of how to calculate a factorial in Python, showing its advanced reasoning capabilities.

Step 7: Analyze the Response

When you run your script, you'll see a response from Claude Opus 5 that explains how to write a factorial function in Python. This demonstrates how the model can handle complex coding tasks and explain its reasoning.

Notice how Claude Opus 5's pricing remains at $5 per million input tokens and $25 per million output tokens. This means you can use it for extensive coding projects without worrying about high costs.

Step 8: Test with More Complex Tasks

Try modifying your prompt to ask Claude Opus 5 to solve a more complex problem:

prompt = "\n\nHuman: You are Claude Opus 5. Please help me design a web scraper that extracts product information from an e-commerce site. Include error handling and explain how to avoid being blocked by the site.\n\nAssistant:"

Run the same code with this new prompt to see how Claude handles advanced tasks like web scraping and ethical considerations.

Summary

In this tutorial, you've learned how to set up your environment to work with Claude Opus 5, how to securely store your API key, and how to send prompts to the model. You've also seen how Claude Opus 5 can assist with coding tasks and complex problem-solving. Remember that Claude Opus 5 is positioned as a powerful model that approaches the intelligence of Claude Fable 5 at half the price, making it an excellent choice for developers and researchers who need advanced AI assistance.

While you can't directly run this code without an API key, this tutorial gives you the foundation for working with Claude Opus 5 in real projects. As you continue to explore, you'll find that Claude's agentic coding and computer use capabilities make it a valuable tool for automation and development tasks.