Fireworks AI launched FireRouter with Opus, a cache-aware routing model optimizing Claude Opus, GLM5.3, and GLM5.3Flash. Internal A/B testing shows a 57% cost reduction per session, dropping from $15.36 to $6.63, with only a 1.5 percentage point accuracy drop (98.1% of Opus alone). The system dynamically routes tasks to balance quality and cost, achieving a 94.2% cache hit rate by directing routine tasks to cheaper models.