A free AI coding agent for JetBrains IDEs. IntelliJ IDEA, PyCharm, WebStorm, GoLand, Rider and the rest: an agent that plans, edits across files and runs your tests.
Install from the Marketplace
In Settings → Plugins → Marketplace, search for MegaBrain and install MegaBrain Code Factory. It needs JetBrains IDEs 2026.1 or later.
An agent, not autocomplete
Give it a task instead of a line to finish: it reads the code, makes the change across files, runs the tests and hands you one diff to review.
Your project’s own tools
It runs the commands your project already uses, Gradle, Maven, pip, npm or anything else, to build and test what it wrote.
Free to start
Free costs nothing and needs no card: the agent in your terminal, your editor and the Mac app, the free models, and your own API keys and local models (Ollama, LM Studio) with no limits from us. Paid plans start at $8 a month (Plus) and go up to $200 (Ultra). They include GLM, Kimi, MiniMax, DeepSeek, Qwen, Grok and Auto with a session limit and a weekly limit you can always see; from Pro ($30) Claude, GPT and Gemini are paid from credits.
Questions
Is there a free AI coding assistant for IntelliJ IDEA?+
Yes: the MegaBrain plugin, on the free plan, for IntelliJ IDEA and the other JetBrains IDEs (JetBrains IDEs 2026.1 or later).
Does it work in PyCharm, WebStorm and GoLand?+
Yes, and in Rider and the other JetBrains IDEs, through the same plugin from the JetBrains Marketplace.
Is it JetBrains AI Assistant?+
No. MegaBrain is a separate plugin, not made by or affiliated with JetBrains, and it does not need a JetBrains AI subscription.
Which models can it use?+
90+ models through one plan: the free models on Free, the included models on the paid plans, Claude, GPT and Gemini from Pro, your own API keys and local models.
How do I start?+
Install MegaBrain Code Factory from the JetBrains Marketplace, open it in the IDE and sign in once.
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