model-routing ai-gateway multi-agent inference-api cost-tracking

Sakana Fugu Ultra routes work across frontier models

Multi-agent routing system coordinates 1-3 models per request, available via AI SDK with no platform markup on inference.

June 23, 2026

Summary

Developers get Claude Mythos/Fable 5-class reasoning without vendor lock-in, with unified cost tracking and failover control through a single API endpoint.

Why it matters

Developers get Claude Mythos/Fable 5-class reasoning without vendor lock-in, with unified cost tracking and failover control through a single API endpoint.

Implementation verdict

Replaces single-model inference calls. Requires only setting `model: 'sakana/fugu-ultra'` in AI SDK. Ready now—try in playground first to validate latency/cost tradeoff for your workload.

Sources

1.Fugu Ultra is built on a pool of publicly accessible frontier models, rather than running as a single model
2.routing work to 1-3 agents depending on the problem
3.AI Gateway provides a unified API for calling models, tracking usage and cost, and configuring retries, failover, and performance optimizations
4.AI Gateway reflects provider pricing with no markup and does not charge a platform fee on inference

Dev Signal

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