GPT-5.1-Codex vs Muse Spark 1.2

GPT-5.1-Codex against Muse Spark 1.2
GPT-5.1-CodexMuse Spark 1.2
Coding index15.355.7
Benchmarks behind it Partial, 2 benchmarks Verified, 5 benchmarks
Output $/Mtok$10.00$4.25
Cost per solved task$0.892$0.64
Context window400K1.05M