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In this video, I’ll be telling you about the new stealth model called Horizon Alpha that has dropped on OpenRouter and exploring whether this could be OpenAI’s upcoming open-source model that’s supposed to come with GPT-5.
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Key Takeaways:
🔥 Horizon Alpha is a new stealth model on OpenRouter, likely OpenAI’s upcoming open-source model or GPT-5.
⚡ The model has impressive token speeds, suggesting it’s either small or uses mixture-of-experts architecture.
✍️ Excels at writing tasks and EQ Bench, can imitate styles without overusing AI-typical patterns like em dashes.
💻 Great for frontend development and SVG creation, but struggles with complex 3D ThreeJS applications.
🚀 Works seamlessly with VS Code extensions like Roo, Cline, and KiloCode for coding assistance.
📊 Scores above Sonnet (thinking) but below Opus (non-thinking) on Aider benchmarks.
🆓 Currently free to use with no limits, 256k context window, and 128k max output tokens.
🤔 Not a reasoning model despite high token output, which limits complex application development.
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Timestamps:
00:00 – Introduction to Horizon Alpha & Is it GPT-5?
01:28 – Benchmark Results & Writing Performance
02:30 – Dart (Sponsor)
03:38 – Horizon Alpha + Roo, Kilo Setup
04:12 – Coding Tests, ThreeJS Failures & Success
06:27 – Model Analysis & Speed Discussion
08:46 – Ending
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