Claude Opus 4.8 vs Muse Spark 1.3: Benchmark Comparison
Claude Opus 4.8 has the higher score on 6 of 11 shared benchmarks; Muse Spark 1.3 leads on 4.
The largest observed score gap is 19.67 pts on Code Migration , where Claude Opus 4.8 leads.
Reported ±1 standard-error ranges overlap on 5 of 11 shared benchmarks with comparable uncertainty data. This is not a pairwise statistical significance test.
Shared benchmark results
Scores and reported standard errors come from the latest visible Vals benchmark version available for both models.
| Benchmark | Claude Opus 4.8 | Muse Spark 1.3 | Gap | Reported uncertainty |
|---|---|---|---|---|
| Vals Index | 55.10% ±1.01 | 53.20% ±1.07 | 1.90 pts | Reported ±1 SE ranges overlap |
| Harvey's Legal Agent Benchmark | 9.58% ±2.15 | 22.92% ±3.42 | 13.33 pts | Reported ±1 SE ranges do not overlap |
| Legal Research Bench | 43.75% ±3.45 | 40.87% ±3.42 | 2.88 pts | Reported ±1 SE ranges overlap |
| EMB | 69.37% ±2.61 | 62.71% ±2.96 | 6.66 pts | Reported ±1 SE ranges do not overlap |
| Finance Agent (v2) | 53.92% ±0.16 | 58.90% ±0.44 | 4.98 pts | Reported ±1 SE ranges do not overlap |
| Tax Agent Bench | 64.91% ±3.17 | 71.93% ±2.92 | 7.03 pts | Reported ±1 SE ranges do not overlap |
| Terminal-Bench Science | 4.29% ±2.44 | 4.29% ±2.44 | 0.00 pts | Reported ±1 SE ranges overlap |
| Code Migration | 47.25% ±4.18 | 27.58% ±4.07 | 19.67 pts | Reported ±1 SE ranges do not overlap |
| ProgramBench | 1.00% ±0.70 | 0.50% ±0.50 | 0.50 pts | Reported ±1 SE ranges overlap |
| Terminal-Bench 4.0 | 23.23% ±1.34 | 10.61% ±1.75 | 12.63 pts | Reported ±1 SE ranges do not overlap |
| Vibe Code Bench v1.1 | 82.72% ±3.08 | 82.86% ±2.90 | 0.13 pts | Reported ±1 SE ranges overlap |
Performance by category
| Category | Claude Opus 4.8 average | Muse Spark 1.3 average |
|---|---|---|
| Legal | 26.67% | 31.89% |
| Finance | 62.73% | 64.52% |
| Science | 4.29% | 4.29% |
| Coding | 38.55% | 30.39% |
Cost and latency
Cost per test appears only where the benchmark reports it for both models. Latency is the measured completion time for that benchmark.
| Benchmark | Claude Opus 4.8 cost | Muse Spark 1.3 cost | Claude Opus 4.8 latency | Muse Spark 1.3 latency |
|---|---|---|---|---|
| Vals Index | $13.14 | $3.38 | 39m48s | 32m42s |
| Harvey's Legal Agent Benchmark | $10.22 | $2.76 | 24m08s | 16m39s |
| Legal Research Bench | $2.82 | $0.65 | 11m54s | 8m51s |
| EMB | $12.06 | $3.55 | 43m52s | 22m55s |
| Finance Agent (v2) | $4.22 | $0.74 | 9m07s | 5m42s |
| Tax Agent Bench | $1.69 | $0.32 | 7m59s | 8m25s |
| Terminal-Bench Science | $23.14 | $4.41 | 1h55m | 1h08m |
| Code Migration | $30.51 | $4.62 | 1h15m | 1h08m |
| ProgramBench | $31.27 | $11.56 | 1h32m | 1h09m |
| Terminal-Bench 4.0 | $17.14 | $7.04 | 1h11m | 1h59m |
| Vibe Code Bench v1.1 | $26.88 | $2.10 | 1h16m | 12m54s |
Results available only for Claude Opus 4.8
- Vals RSI Index
- LegalBench
- MortgageTax
- TaxEval v2
- MedCode
- MedScribe
- GPQA Diamond
- MMLU Pro
- MMMU Pro
- SAGE
- LiveCodeBench
- SkillsBench
- SWE-bench
- Public Benefits Bench v1.1
- Time Horizon Index: KSP
Results available only for Muse Spark 1.3
- ProofBench v1.1
- IOI
- CyberBench v1.1