Anthropic has introduced significant improvements not only in performance but also in security and user experience with Claude Sonnet 4.5. The company states that the new model offers a significant leap forward in reasoning and mathematical skills compared to previous versions. Claude Sonnet 4.5 topped the SWE-bench Verified benchmark, which measures real-world software development capabilities, and achieved a 61.4% success rate in the OSWorld benchmark, which evaluates practical tasks on a computer.
New VS Code Plugin
The release of the model also brings significant updates to Claude Code. Users can now save their work and return to previous stages, a revamped terminal interface provides greater flexibility, and the new VS Code plugin allows Claude to be integrated directly into the development environment.
There are also improvements on the API side that simplify development for developers. The context editing feature automatically cleans up old content, making long dialogs more efficient. A new memory tool that can carry information across context boundaries ensures continuity in long-running tasks.
Additionally, Anthropic last month opened the Claude for Chrome extension to those who signed up to its waiting list and released the Claude Agent SDK, the foundation of Claude Code, for developers.
No Price Increase for New Model
Claude Sonnet 4.5 is available on the Claude Developer Platform, Amazon Bedrock, and Google Cloud Vertex AI. Pricing remains the same as the previous version: $3/$15 per million tokens.
Anthropic emphasizes that this model is “the most reliable edge model yet.” Launched with AI Safety Level 3 protections, Claude Sonnet 4.5 features filters that enhance the detection of risky content and is optimized to minimize unwanted behaviors such as manipulation or control-seeking.
As part of a temporary feature, Anthropic has launched a new experience exclusively for Max subscribers. This service, called “Imagine with Claude,” is a five-day research preview showcasing the model’s real-time software generation capabilities.
