Across 27 shared benchmarks, Claude Opus 4.8 scores higher on 5 and Muse Spark 1.3 on 22. The widest gap is TauBench V3 - Banking, where Muse Spark 1.3 scores 52.4 against 34.2. Muse Spark 1.3 is the cheaper of the two on tracked API pricing ($1.25 against $5.00 per million input tokens).
Best tracked score per model per benchmark (default configuration; source-attributed). ↓ marks lower-is-better metrics. Open either model for its full surface, provenance and pricing. Quoted rates are the price-setter row we currently track for each model — its direct or vendor-official listing where one exists (direct, meta-official), otherwise the lowest tracked offer.