How to Use Kilo Code for 100% Free (Using a Frontier Model)

Some people suspect this is another stealth model from OpenAI

Kilo Code is a 100% free, open-source AI agent extension for VS Code with over 180,000 installs.

While most AI coding agents (hint: Cursor) require paid subscriptions to start using their underlying models, we've partnered with OpenRouter to bring you access to a powerful frontier model for free. And by free we mean really free: No rate limits and fast code generation.

The Model: Horizon Beta

Horizon Beta is a stealth, frontier AI model that many in the developer community speculate originates from OpenAI (some people even call it GPT-5).

This model can be better than Sonnet or Opus 4, especially in tasks like generating good-looking UIs:

Horizon Beta is a stealth model, which is a fancy term for: “We won’t tell you who is behind this model and make it 100% free, in return we’re getting usage stats”. The last “stealth” model announced by OpenRouter was by OpenAI (we actually ended up on the front page of Hacker News with a blog post speculating this).

How to use Horizon Beta in Kilo Code

Follow 3 simple steps

1. Install our VS Code extension if you haven’t already (we’re at 180,000+ installs!) and sign up

2. Change your default model to Horizon Beta in Settings:

3. You’re done. Start typing!