JetBrains logo on a white background, for the Junie CLI 26.11.1 guide

Junie CLI 26.11.1: Power-User Guide to Custom Themes, Subagent Messages and Gemini 4 Carbon

by

Last updated: November 13, 2026

Junie CLI 26.11.1, released November 10, 2026 as build 4020.7, adds Gemini 4 Carbon support, custom JSON color themes and direct messages to running subagents. It also fixes Windows startup with PowerShell 7 and Git Bash, image pasting, terminal icons and remote MCP authentication in JetBrains’ terminal coding agent.

Our Junie Eco mode guide covered the October releases. This guide covers what changed in November and how to configure the new options.

Contents

What is new in 26.11.1

The Junie CLI What’s New page lists these changes for November, newest first.

Release (build) Date Changes
26.11.1 (4020.7) November 10, 2026 Gemini 4 Carbon support; custom themes; send messages directly to running subagents; Windows fixes for PowerShell 7 and Git Bash startup, image pasting and terminal icons; remote MCP authentication fix
26.11.3 (3959.6) November 9, 2026 Claude Fable 5.2 support
26.11.3 (3959.5) November 3, 2026 Fixes for process hangs, disk filling and a memory leak; crashes from very large output strings; an error that blocked interaction with models

The version labels do not run in order on that page, so the build number is the clearer guide: build 4020.7 is the newest stable release listed.

Custom color themes

Junie CLI ships three built-in themes. Auto picks dark or light from your terminal or operating system and uses the background color your terminal reports. Dark and Light each use their own background. Themes change the colors of the interface, diffs and Markdown replies, not your terminal’s color scheme (Junie theme documentation).

To create your own theme:

  1. Create a themes folder in the Junie CLI home directory: ~/.junie/themes, or $JUNIE_HOME/themes if JUNIE_HOME is set.
  2. Add a JSON file. The file name becomes the theme name, so nord.json appears as nord. The names auto, dark and light are reserved.
  3. Use "extends": "dark" or "light" so you only need to set the tokens you want to change. Without it, you must define every token.
  4. Restart Junie CLI, because theme files load only at startup.
  5. Run /themes (alias /theme) and select your theme, or change it with the Theme setting in /settings.

A theme file accepts only three top-level keys: extends, defs for named colors, and theme, which maps tokens such as primary, accent, background, diff backgrounds and syntax colors to values. Colors must be six-digit #RRGGBB hex strings or names from defs or the built-in palette. Short hex and alpha values are rejected, and one file holds one color scheme, so a dark and a light variant need two files.

A definition that reuses a palette name, such as green-300, overrides that color everywhere it is inherited. Junie validates themes at startup, lists errors above the theme list in /themes, and falls back to Auto if your selected theme cannot load.

Subagents and subagent messages

Subagents are task-specific helpers that run in their own context and return results to the main agent. Junie CLI delegates to them automatically by matching each subagent’s name and description to the task (Junie subagents documentation).

The 26.11.1 release notes add the ability to send messages directly to running subagents. The documentation does not yet describe the exact steps, but the keyboard reference lists Ctrl+T to open subagent tasks and Ctrl+O to open the selected subagent’s transcript, which is where running subagents are visible.

Custom subagents are Markdown files with YAML frontmatter, stored in .junie/agents/ or .agents/ in a project, or the same folders in your home directory. Useful frontmatter fields include:

Field Purpose
description Required; tells the main agent when to delegate
tools / disallowedTools Allow or deny tool groups such as Read, Bash, Grep, Edit and WebSearch
mcpServers Limit the subagent to named MCP servers
model, reasoningLevel Fix the model and effort for this subagent
maxTurns Cap the number of steps
permissionMode default, acceptEdits, dontAsk, bypassPermissions or plan

Subagents cannot be called with a slash command. To run one as the main agent for a session, use junie --agent code-review-helper "Review my staged changes" or set JUNIE_AGENT. Junie also offers to import agent files it finds in .cursor/agents/, .claude/agents/ or .codex/agents/.

In the Early Access version, /settings then Subagents chooses between SameModelOnly, where subagents use the main model only for parallel work, and Auto, the default, which may pick cheaper capable model tiers for suitable work.

Gemini 4 Carbon and other new models

Gemini 4 Carbon support is listed in 26.11.1, one day after Claude Fable 5.2 support arrived in build 3959.6. For Google’s description of the Gemini 4 family, see our Gemini 4 Hydrogen guide.

The subagents documentation says to start Junie and use /model, or pass a name accepted by the --model flag, to see the model names available in your setup. Which models you see depends on whether you sign in with JetBrains AI or bring your own key. A subagent’s model field accepts the same names, so you can, for example, keep a heavier model for the main agent and give a read-only search subagent a lighter one.

Windows and remote MCP fixes

On Windows, 26.11.1 fixes startup with PowerShell 7 and Git Bash, image pasting and terminal icons. It also fixes remote MCP authentication.

Per the MCP configuration documentation, remote servers that need OAuth appear in /mcp with an Authorization required status. Select the server, choose Authorize, sign in on the browser page that opens, and confirm the status changes to Active. Servers you add by hand to .junie/mcp/mcp.json can instead pass a headers object, such as a bearer token, alongside the server URL. Keep secrets out of project-scope files that are committed to version control.

How to update

  1. Inside Junie CLI, run /update to check for and download the new version.
  2. Run /restart to apply the update and reopen your current session. This needs the managed junie launcher.
  3. Run /themes to confirm any custom theme loaded without errors.
  4. Run /mcp and re-authorize any remote server still showing Authorization required.
  5. Open /model to check that Gemini 4 Carbon appears for your sign-in method.

If you use Junie inside an IDE, see our JetBrains Air in IDEs guide. For a comparable terminal agent, see the GitHub Copilot CLI 1.0.111 guide and our Copilot in JetBrains Air guide.

Frequently asked questions

When was Junie CLI 26.11.1 released?

JetBrains lists Junie CLI release 26.11.1, build 4020.7, on its What’s New page with a date of November 10, 2026. It follows build 3959.6 from November 9, which added Claude Fable 5.2 support.

What is new in Junie CLI 26.11.1?

The release adds Gemini 4 Carbon support, custom color themes and the ability to send messages directly to running subagents. It also fixes Windows startup with PowerShell 7 and Git Bash, image pasting, terminal icons and remote MCP authentication.

Where do Junie CLI custom theme files go?

Put JSON theme files in a themes folder in the Junie CLI home directory, which is ~/.junie/themes by default or $JUNIE_HOME/themes if that variable is set. Restart Junie CLI, then pick the theme with /themes.

Can I start a Junie subagent manually?

Not with a slash command. Junie delegates to custom subagents automatically by matching their name and description. To run a custom agent as the main agent for a whole session, start Junie CLI with –agent followed by the agent name, or set JUNIE_AGENT.

How do I update Junie CLI to the latest version?

Run /update inside Junie CLI to check for and download an update, then run /restart to apply it and reopen the current session. The /restart command requires the managed junie launcher.

Sources

Related answers

Leave a Comment