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IntelliJ IDEA 2026.3 Ships Agents Into the IDE, Makes Debugging Visible, and Settles Long-Neglected UI Debts

By 终码一生 · Nov 11, 2026

Read original on juejin.cn ↗ Google Translate ↗ Alt translation

This release turns agent use from a bolted-on plugin into a first-class IDE workflow, letting teams keep their existing agent subscriptions while getting a structured review loop. The auto-reporting of error and UI freeze telemetry changes the privacy calculus for enterprises, since it ships on by default and must be explicitly disabled.

Summary

The biggest structural change is Air becoming a first-class, bundled agent development layer. It detects existing ACP-compatible agents like Claude Code and Codex, reuses your current provider subscriptions and API keys, and lets you anchor review comments directly on diff lines to send feedback back to the agent. Skills, MCP configs, and chat history migrate from AI Assistant automatically.

Debugging gets a triple boost: return values now appear in the Variables view at method exits; the Hibernate Debugger plugin shows generated SQL, bound parameters, HQL/JPQL, and source lines for repository calls; and the ij-debugger skill gives agents access to log points and runtime diagnostics that persist past the debug session. Spring Security failures inject an explanatory header into the HTTP response to show which rule or permission rejected a request.

Everyday improvements include a Home window that opens a blank file or terminal without loading a project, built-in SSH remote development with Linux Light mode, a terminal on libghostty compatible with Neovim and AI agents, and sound notifications for build, test, and agent events. Database support adds a DuckDB-backed Workspace data source for cross-database joins from one SQL console. JetBrains reports over 1000 bug fixes and 200+ performance fixes, and from 2026.3 it automatically sends sanitized error and UI freezes reports unless disabled.

Takeaways

— JetBrains Air is bundled and enabled with the IDE, replacing the EAP plugin, and supports any ACP-compatible agent with existing subscriptions and API keys.

— Reviewing agent changes happens via anchored comments on diff lines that return directly to the agent, closing the feedback loop inside the editor.

— Method return values are now displayed in the Variables view when a breakpoint hits at a method exit.

— The Hibernate Debugger plugin shows generated SQL, bound parameters, HQL/JPQL, and source lines for repository calls, filterable by transaction or duration.

— The ij-debugger skill keeps log points and process output available after a debugging session ends, and avoids invalid breakpoint positions like closing braces.

— Spring Security requests rejected with 401/403 inject an x-spring-debugger-security-decisions header naming the rule, filter, and permission that caused the rejection.

— The Home window replaces the welcome screen so users can open a blank file, terminal, or Git operation without loading a project.

— Remote development is built in without JetBrains Gateway, uses OpenSSH, and Linux backends support Light mode for editing before the remote IDE fully starts.

— The built-in terminal now runs on libghostty, improving compatibility for Neovim, tmux, and AI agent terminal protocols.

— A Workspace data source on an in-memory DuckDB engine allows joining tables from multiple database connections in one SQL console.

— Java 28 Early Access, Jakarta Persistence 4 / Hibernate 8 createNamedQuery support, and full Scala 3.10 with faster sbt 2.x imports are included.

— 2026.3 fixes over 1000 bugs and 200+ performance issues, including Gradle/Maven sync freezes, Kotlin K2 deep type hangs, and memory leaks in closed projects.

— Starting with 2026.3, error and UI freeze reports are automatically sent to JetBrains after sanitization; the setting can be disabled.

Conclusions

JetBrains is separating agent orchestration from AI chat, which means the IDE treats agents as a workflow tool with its own review cycle rather than a chat widget with code generation.

The decision to not lock agents to JetBrains AI and instead adopt ACP is a bet that agent clients are a commodity; the IDE's differentiator becomes the management and review surface it provides.

Auto-reporting error and UI freezes with sanitization is a quiet trade-off: users get faster fixes, but the default-on telemetry will likely trigger scrutiny in privacy-sensitive shops.

Debugger improvements like return values and Hibernate tracing target the daily friction of enterprise Java work, signaling that JetBrains still prioritizes traditional server-side development over AI-only features.

The libghostty terminal collaboration points to an ecosystem where terminal emulation becomes a shared library, letting JetBrains keep up with modern terminal protocol demands without reinventing them.

Concepts & terms

Agent Client Protocol (ACP)

An open protocol that lets different agent clients (like Claude Code, Codex) communicate with an IDE or host environment, so tools can detect and integrate existing agents without forcing a specific vendor.

Workspace data source

An in-memory DuckDB-based source inside the IDE that lets you query and join tables from multiple distinct database connections in a single SQL console, avoiding data export steps.

libghostty

The core terminal emulation library from the Ghostty terminal emulator project, now used by IntelliJ's built-in terminal to improve compatibility with modern terminal protocols used by Neovim, tmux, and AI agents.

Light mode (remote development)

A remote development feature where users can edit files, use the terminal, and search while the remote IDE is still downloading; it switches to the full IDE seamlessly once ready.

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