GPT-6 Sol vs Union Alpha (Stealth)

A direct, empirical evaluation of GPT-6 Sol (OpenAI) against Union Alpha (Stealth) (OpenRouter & OpenCode).

GPT-6 Sol

Developed by OpenAI · Proprietary Frontier Workhorse parameters

High-efficiency agentic software development, OSWorld computer use, repository refactoring, and enterprise workflow execution at 80% lower cost per task than Claude Opus.

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 GPT-6 Sol Union Alpha (Stealth)
SWE-bench Verified 68.8% 74.2%
MMLU-Pro 90.8% 89.8%
MATH-500 96.4% 95.4%
Context Window 1,000,000 tokens 256,000 tokens
Input Pricing (per 1M) $2.00 $0.00
Output Pricing (per 1M) $10.00 $0.00