Claude 3.7 Sonnet vs Union Alpha (Stealth)
A direct, empirical evaluation of Claude 3.7 Sonnet (Anthropic) against Union Alpha (Stealth) (OpenRouter & OpenCode).
Claude 3.7 Sonnet
Developed by Anthropic · Proprietary parameters
Enterprise software engineering, full-repo refactoring, and agentic workflows.
Union Alpha (Stealth)
Developed by OpenRouter & OpenCode · Multi-Model Ensemble Mixture parameters
Terminal coding agents, pull-request synthesis, multi-model consensus verification, and zero-cost autonomous refactoring.
| Metric | Claude 3.7 Sonnet | Union Alpha (Stealth) |
|---|---|---|
| SWE-bench Verified | 70.3% | 74.2% |
| MMLU-Pro | 82.1% | 89.8% |
| MATH-500 | 96.2% | 95.4% |
| Context Window | 200,000 tokens | 256,000 tokens |
| Input Pricing (per 1M) | $3.00 | $0.00 |
| Output Pricing (per 1M) | $15.00 | $0.00 |