Anthropic has launched its next-generation AI models, Claude Opus 4 and Claude Sonnet 4, as part of the Claude 4 update. These models are positioned as advancements in AI coding, reasoning, and agentic capabilities. The Claude 4 update includes new developer tools, improved memory functions, and enhanced agent workflows.

Both models introduce "extended thinking with tool use" in beta, allowing Claude to alternate between internal reasoning and external tools like web search. They support parallel tool execution, improved memory handling, and enhanced instruction-following. Opus 4 can create and reference memory files when granted file access, increasing contextual understanding and long-term coherence.

Claude Opus 4 is touted as the most powerful coding model to date, with benchmarks including SWE-bench (72.5%) and Terminal-bench (43.2%). It is capable of sustained performance across complex, multi-step tasks and supports agent applications requiring persistent focus and reasoning.

Claude Sonnet 4 is described as a substantial upgrade from Sonnet 3.7, balancing high performance with efficiency. It is claimed to achieve a 72.7% score on SWE-bench and is designed for both internal use and third-party deployment. GitHub has adopted Sonnet 4 as the core of its new Copilot coding agent.

Both models are accessible via Claude Pro, Max, Team, and Enterprise plans, with Sonnet 4 also available to free-tier users. Pricing remains unchanged from the previous generation. The Claude 4 launch is available across the Anthropic API, Amazon Bedrock, and Google Cloud Vertex AI.

According to Anthropic, both models are 65% less likely to take shortcuts in agentic tasks compared to Sonnet 3.7. “Thinking summaries” condense longer reasoning chains for easier interpretation, and a Developer Mode offers full process transparency for advanced users.

Anthropic has rolled out four new capabilities on its API: a code execution tool, an MCP connector, a Files API, and a prompt caching function. These tools aim to help developers build more robust AI-driven applications and agents.

At its inaugural developer conference, Anthropic introduced Claude 4 artificial intelligence (AI) models. The San Francisco-based AI firm unveiled Claude Opus 4 and Claude Sonnet 4 models and announced new capabilities including Extended Thinking with tool use. Opus 4 is said to be state-of-the-art (SOTA) in coding, tool use, and writing.

Claude Code is now generally available, with beta extensions in VS Code and JetBrains. It is also among the models available on GitHub. Anthropic's latest large language models (LLMs) heavily emphasize coding capabilities and agentic functions. Both Opus 4 and Sonnet 4 are hybrid models with two modes: near-instant responses and Extended Thinking for deeper reasoning.

Opus 4 is the company's flagship-tier AI model, scoring 72.5 percent on the SWE-Bench and 43.2 percent on the Terminal-Bench benchmarks, which measure coding capabilities.

Claude Sonnet 4 is significantly improved compared to its predecessor, achieving 72.7 percent on SWE-Bench (SOTA) based on internal evaluation. While it falls short of Opus 4's score in other domains, Anthropic says the model balances performance and efficiency better than the flagship LLM.

Claude Opus 4 can maintain long-term task awareness with improvements in its memory. Anthropic has also addressed the issue of models taking shortcuts to complete tasks. During extended thinking, both models can use tools, allowing them to alternate between native reasoning and exploring external information (such as web search) to improve responses. Other improvements include the ability to use tools in parallel and greater prompt adherence.

The Opus 4 and Sonnet 4 models are available to Claude Pro, Max, Team, and Enterprise subscribers. Sonnet 4 is also available to free users. Developers can access these LLMs via the Anthropic API, as well as on Amazon Bedrock and Google Cloud's Vertex AI. Opus 4 costs developers $15 per million input tokens and $75 per million output tokens, while Sonnet 4 is priced at $3 per million input and $15 per million output tokens.

Beyond the new AI models, Anthropic also announced new features and made Claude Code generally available. First introduced in February as a research preview, Claude Code is an agentic coding tool that can perform a wide range of coding tasks. A beta extension of the feature is now available in VS Code and JetBrains. Additionally, the company is also releasing a Claude Code software development kit (SDK), which is available in beta on GitHub.