JetBrains Sandbox

Use this skill to give an agent a running IntelliJ instance and the means to control it. The setup provides IntelliJ IDEA, MCP Steroid, and a minimal browser desktop using TigerVNC, Openbox, and noVNC. It is not tied to testing a particular plugin or following a prescribed IDE workflow. The HTTP transport works through sandbox HTTPS proxies that break WebSocket upgrades.

Boundaries

• Tested on Debian 13, Linux x86-64, with Bun available. Allow roughly 8 GB RAM and 10 GB free disk for the IDE, archives, plugins, and caches.
• Installation needs root for apt and creating the IDE account. With dependencies preinstalled, a non-root account can use --skip-deps and run as itself.
• No public tunnel or viewer password is created. The default bind is loopback. Use --host 0.0.0.0 only behind the user's authenticated sandbox port forwarding. Binding only to 127.0.0.1 may make the platform report that nothing is listening.
• Raw VNC and MCP remain bound to loopback even when the viewer is externally reachable.
• If a secure preview proxy rewrites Host, pass its exact browser-facing origin with --origin https://your-preview-host. Arbitrary forwarded headers are not trusted.
• Do not accept JetBrains agreements, start a trial, sign into services, copy the agent's credentials into the IDE, or dismiss unrelated dialogs automatically.
• All runtime state defaults to the current worktree's ignored .kilo-dev/jetbrains-sandbox/. Never point --dir at the workspace itself.
• Never overwrite plugin jars while that state directory's IDE is running. Stop first.
• Do not stop another session's IDE or alter the user's workspace ownership. A supplied --project must already be accessible to the selected non-root --user.

Pinned Setup