IntelliJ IDEA Goes LSP: Java and Kotlin Intelligence Comes to VS Code, Cursor, and Agentic Flows

IntelliJ IDEA, the leading Integrated Development Environment (IDE) for Java and Kotlin professional development, is now offering its smart language features through an LSP (Language Server Protocol) format in third-party editors, starting with VS Code and its forks such as Cursor. This development comes as agentic development increasingly automates code implementation, leaving developers to focus on fewer manual editing tasks.

The Java & Kotlin by IntelliJ IDEA extension, powered by IntelliJ IDEA's Java and Kotlin language technology, provides a focused set of capabilities to VS Code-based editors. These include code analysis features and quick-fixes similar to those offered by Red Hat's and Oracle's extensions for Java. The extension can be installed from the Visual Studio Marketplace and the Open VSX registry.

After installation, users can open their Java or Kotlin projects in VS Code or Cursor, which the extension will analyze, import projects with Maven, Gradle, or Bazel build files, and then enable Java and Kotlin language features within the editor.

The extension is currently in a preview phase and is free to use, with each build renewing the evaluation period of 30 days. Upon completion of the preview, the extension will require an IntelliJ IDEA Ultimate subscription for continued use. During this preview period, the same license will allow users to utilize IntelliJ IDEA's Java and Kotlin capabilities across various environments, including the desktop IDE, VS Code-based editors, and other supported platforms. Pricing options are available on the official website.

For pure Kotlin projects, JetBrains continues to develop and maintain the Kotlin LSP, which is Apache 2.0 licensed and available for free use, either directly or via extensions on the Visual Studio Marketplace and Open VSX registry. The VS Code extension is just one milestone in JetBrains' ongoing development journey to bring IntelliJ IDEA's intelligence to users wherever they work.

The company believes Java and Kotlin development is best achieved within IntelliJ IDEA but recognizes the practical reasons teams may choose to work in other environments. As such, they are already working on supporting fully agentic, terminal-based workflows and plan to share initial results and opportunities to test agent plugins in the near future.

Feedback from users during this preview phase is crucial in shaping the extension as it moves towards a stable 1.0 release.