Sakana AI's Fugu Ultra Multi-Agent System Launches on OpenRouter, Outperforms Fable 5 in Benchmarks

According to Beating monitoring, Sakana AI's Fugu Ultra, a multi-agent coordination system, has launched on OpenRouter. The system dynamically orchestrates GPT-5.5, Gemini 3.1 Pro, and Claude Opus 4.8 through a single interface and outperformed Anthropic's flagship models Claude Fable 5 and Mythos Preview in academic and programming benchmarks. Fugu Ultra employs techniques from ICLR 2026 papers Trinity and Conductor, with specialized role assignment: Gemini 3.1 Pro handles common sense queries, GPT-5.5 manages math computations, and Claude Opus 4.8 provides code auditing.

On OpenRouter, Fugu Ultra offers a 1 million token context window with maximum 128K token output and supports tool calling and multimodal inputs. Pricing is $5 per million input tokens and $30 per million output tokens, with cached reads at $0.50 per million tokens.