Enthropic's recent release of Cloud 4 Opus and Cloud 4 Sonnet has redefined the landscape of coding models. These state-of-the-art models are now leading the industry, outperforming competitors like OpenAI's Codex and Gemini 2.5 Pro.

Cloud 4 Opus is the new number one coding model, excelling in long-term memory, tool use capabilities, and complex workflows. It is priced at $15 per 1 million input tokens and $75 per 1 million output tokens.

Cloud 4 Sonnet, on the other hand, delivers a significant upgrade over Sonnet 3.7, scoring record highs on Swaybench. It shines in reasoning speed and precision, making it ideal for real-time tasks and scalable applications. The pricing for Sonnet 4 is $3 per 1 million input tokens and $15 per 1 million output tokens.

Both models have demonstrated their prowess on the software engineering Swaybench, outperforming their competitors in categories such as Aentic terminal coding, graduate-level reasoning, and Agentic tool use.

These powerful coding models, when combined with a reputable AI coding agent like Klein, can unlock unprecedented capabilities. Developers can leverage these tools to create, edit, and execute complex applications with ease, all while maintaining control and autonomy.

To get started with the powerful combination of Cloud 4 Opus/Sonnet and the Cline coding assistant, follow these steps:

1. Install VS Code or any other IDE that supports the Cline extension. VS Code is recommended as it is completely free.
2. Install the Cline extension through the VS Code marketplace. Simply click the "Install" button and open the extension within your IDE.
3. Make sure you have the latest version of the Cline extension installed. Restart the extension after the installation is complete.
4. In the left-hand panel, you will see the Cline extension. Click on the "Settings" tab.
5. Provide your API key from the Anthropic provider. You can obtain a free API key with $6 or $20 credits to try out the Opus and Sonnet models.
6. Set the Cline extension to "Autoproof" mode, which will allow it to work autonomously without your direct intervention.

With these steps, you have successfully set up the Cline extension and integrated it with the powerful Cloud 4 Opus and Sonnet coding models. You are now ready to witness the impressive capabilities of this AI-powered coding assistant.

To benchmark the capabilities of Opus 4 and Sonnet 4, we tasked the AI coding agent Klein with creating a visually appealing SaaS landing page with animations. Both models were put to the test, and the results were impressive.

Using Opus 4, Klein was able to generate a complete SaaS landing page with a clean and modern design, featuring smooth animations and various interactive elements. The page showcased trusted companies, highlighted key features, and provided a visually engaging user experience. This demonstration showcased Opus 4's exceptional ability to handle complex front-end development tasks, delivering a high-quality output with minimal intervention.

In comparison, the Sonnet 4 model also performed admirably, producing a landing page that was on par with the Opus 4 version. While the Sonnet 4 page may have slightly differed in its aesthetic, it still exhibited a strong grasp of front-end design principles, responsive layout, and seamless animations. This highlights the versatility and power of the Sonnet 4 model, making it a viable and cost-effective alternative to Opus 4 for certain front-end development tasks.

The benchmarking exercise demonstrated the remarkable capabilities of both Opus 4 and Sonnet 4 in the realm of front-end development. These state-of-the-art coding models have the potential to revolutionize the way developers approach complex coding challenges, empowering them to create visually stunning and highly functional applications with increased efficiency and reliability.

To build an autonomous browser agent using Opus 4 and Cline, follow these steps:

1. Install the Cline extension in your IDE (e.g., Visual Studio Code).
2. Provide your Anthropic API key in the Cline extension settings.
3. Instruct Cline to create a complete autonomous browser agent using the BrowserBase architecture.
4. Cline will then:
   • Scrape the necessary documentation from BrowserBase.
   • Install the BrowserBase application locally.
   • Develop the front-end and connect it to the back-end API.
5. Once the agent is set up, you can interact with it by sending instructions, such as taking a screenshot of a webpage.
6. The agent will execute the task autonomously, saving the screenshot in the designated folder.

This process showcases the impressive capabilities of Opus 4 in combination with the Cline coding agent, allowing for the rapid development of complex, autonomous applications.

The release of Enthropic's Cloud 4 Opus and Cloud 4 Sonnet models has marked a significant leap in AI development. These state-of-the-art coding models are redefining the capabilities of developers and AI engineers.

Cloud 4 Opus is now the leading coding model, outperforming competitors on complex workflows thanks to its reliable long-term memory and tool use capabilities. Cloud 4 Sonnet also delivers a substantial upgrade, excelling in reasoning speed and precision, making it ideal for real-time tasks and scalable applications.

While the pricing of these models may seem high, their exceptional performance justifies the investment. The benchmarks demonstrate their dominance over other models, including OpenAI's Codex and the new Gemini 2.5 Pro.

By combining these powerful models with a reputable AI coding agent like Klein, developers can unlock even greater capabilities. The seamless integration allows for autonomous code creation, file editing, terminal-based commands, and web browsing, all with the user's permission or fully autonomously.

The impressive demonstrations showcased in this content highlight the transformative potential of these models. Developers and AI engineers are encouraged to explore the opportunities presented by Cloud 4 Opus and Cloud 4 Sonnet, as they redefine the boundaries of what's possible in the world of coding and software development.