Sakana AI releases Fugu Ultra v2, claims it beats GPT-6 Astra on some tests

Sakana Fugu is an AI system that Sakana AI began offering generally in June. It selects models based on the difficulty of a user's request and, when needed, builds and coordinates a team of dedicated AI agents. Because the processing stays internal, users can treat it like a single AI model through the API.

The latest version, Fugu Ultra v2, sits at the top of the Fugu lineup. On some benchmarks, it is said to outscore GPT-6 Astra, Claude Fable 5.1 and Claude Fable 5, even though those three models are not among its partners. This suggests the gains come from how Fugu combines and orchestrates other models rather than from any single partner model.

Fugu Max, by contrast, focuses on cost performance, newly adding Nvidia's Nemotron open-weight series and others as partners. How much these claimed advantages translate into real-world use will likely hinge on whether the benchmark wins hold up in practice and whether the lower output prices attract developers away from rival models.