- Manually prompting multiple models and stitching answers together is tedious and error-prone
- Single frontier models still hallucinate or miss blind spots on hard research tasks
- Running diverse model panels yourself means managing tools, context, and synthesis logic
- Frontier-level performance usually comes with frontier-level pricing
OpenRouter’s new Fusion API directly solves these.
It routes your prompt in parallel to a panel of models (with tools), uses a judge to extract consensus/contradictions/unique insights, then has a synthesizer produce the final grounded response — all server-side.
Key results from their DRACO benchmark (100 hard research tasks):
- Budget panel (Gemini 3 Flash + Kimi + DeepSeek) matched or beat solo GPT-5.5 / Opus 4.8
- Came within ~1% of Claude Fable 5 performance at roughly half the cost
- ~75% of gains came from the synthesis step
You can also customize the panel and synthesizer models.
This feels like a meaningful step toward reliable multi-model agent workflows without having to build the orchestration yourself.
OpenRouter (@OpenRouter)
Introducing the Fusion API, the smartest compound model in the market.
Fusion achieves Fable-level intelligence at half the price.
How it works 👇
— https://nitter.net/OpenRouter/status/2065856853989270011#m