Hardest reasoning tasks
Choose GPT-5.6 Sol
GPT-5.6 Sol scores 47 on the Artificial Analysis Intelligence Index, against 33.7 for Muse Spark 1.1.
Choose GPT-5.6 Sol for the hardest reasoning tasks and reasoning over long documents; on the other points the two are level or the data is missing.
Each answer below comes straight from the published prices, specifications and independent benchmark results.
Choose GPT-5.6 Sol
GPT-5.6 Sol scores 47 on the Artificial Analysis Intelligence Index, against 33.7 for Muse Spark 1.1.
Choose GPT-5.6 Sol
GPT-5.6 Sol scores 84% on Long-context reasoning (AA-LCR), against 77.7% for Muse Spark 1.1.
| GPT-5.6 Sol | Muse Spark 1.1 | |
|---|---|---|
| Provider | OpenAI | Meta |
| Category | Language models | Language models |
| Status | Generally available | Legacy |
| Headline price | $8.00 / 1M tokens | No data |
| Input | $4.00 / 1M tokens | No data |
| Output | $20.00 / 1M tokens | No data |
| Cached input | $0.40 / 1M tokens | No data |
| Context window | 1.05M | 1.05M |
| Max output | 128k | No data |
| Released | Jul 9, 2026 | Jul 9, 2026 |
| Knowledge cutoff | February 2026 | No data |
| Licence | Proprietary | Proprietary |
| Capabilities | Vision, Reasoning, Tool calling, Structured output, Prompt caching, Batch API | Vision, Tool calling |
| API model id | gpt-5.6-sol | muse-spark-1.1 |
Leader in bold.
| Benchmark | GPT-5.6 Sol | Muse Spark 1.1 |
|---|---|---|
| Intelligence Index | 47 | 33.7 |
| SciCode | 57.1% | 58.8% |
| GPQA Diamond | 94.1% | 89.8% |
| Humanity's Last Exam | 49.5% | 46.2% |
| Long-context reasoning (AA-LCR) | 84% | 77.7% |
| Terminal-Bench Hard | 65.9% | No data |
| IFBench (instruction following) | 72.7% | No data |
| τ²-Bench (agentic tool use) | 85.1% | No data |
| MMMU-Pro (visual reasoning) | 83.4% | No data |
Independent evaluations by Artificial Analysis, run the same way for every model, at the reasoning setting shown. Percentages unless marked as an index.
Choose GPT-5.6 Sol for the hardest reasoning tasks and reasoning over long documents; on the other points the two are level or the data is missing.
A price comparison is not possible: one of them has no comparable published price.
GPT-5.6 Sol reads more per request: 1.05M tokens against 1.05M.
GPT-5.6 Sol is made by OpenAI and Muse Spark 1.1 by Meta. A price comparison is not possible: one of them has no comparable published price. GPT-5.6 Sol reads more per request: 1.05M tokens against 1.05M. Only GPT-5.6 Sol offers reasoning, structured output, prompt caching, batch api.