Grok 4.5 is dominating the efficiency frontier while building the strongest all-around case in AI coding It is outperforming Claude Fable 5 and GPT-5.6 Sol across several demanding real-world coding and agentic benchmarks while delivering dramatically better cost efficiency • #1# on Long-Horizon Terminal-Bench for both mean reward and strict binary pass rate • #1# among models operating under a defined $5 workload • #1# on VulcanBench v3 with 91.3%, completing 21 of 23 tasks • GPT-5.6 Sol and Claude Fable 5 both finished at 87.0% • 99% on SignalDesk V1, fixing 69 of 70 tasks at only $0.074 per fix On SignalDesk, GPT-5.6 Sol cost around 2.5× more per fix, while Claude Fable 5 cost around 5.6× more And Grok 4.5 has now recorded the largest week-over-week increase in usage of any model inside Augment Code’s Cosmos picker Grok 4.5 is winning across capability, efficiency and real-world developer adoption It is becoming one of the strongest overall models for serious coding, long-running agentic tasks and large real-world codebases where actual engineering happens Grok is redefining the efficiency frontier