Union Alpha
Analysis Summary
Union Alpha comes from Stealth. It launched in September 2026, making it a current-generation release.
Its 262K-token context window is larger than 71% of the models we list, suiting long documents, large codebases, and retrieval-heavy workloads. Crucially for business adoption, Union Alpha combines tool use, function calling, and vision input in a single model, letting teams consolidate several use cases instead of stitching together multiple services.
At $0.000 input and $0.000 output per 1M tokens, Union Alpha is free to use. Union Alpha is worth evaluating where Stealth’s ecosystem and the model’s specific capabilities fit your workflow.
Rankings consider pricing, capabilities, benchmarks, and real-world applicability and are refreshed as new models launch. Feedback?
How Union Alpha compares
Its 262K-token context window is larger than 71% of the models we list. Union Alpha is currently free to use via OpenRouter.
Dark bar = input · light bar = output, scaled to the priciest peer.
1M tokens ≈ 8 full-length novels or ~2,500 pages of business documents in a single request.
About Union Alpha
Union Alpha is a multimodal model built for research, coding, and agentic workflows, while delivering frontier-level performance across a broad range of general-purpose tasks. Union Alpha is a stealth model..
Frequently asked questions about Union Alpha
How much does Union Alpha cost?
Union Alpha is currently available for free via OpenRouter.
What is the context window of Union Alpha?
Union Alpha has a context window of 262,144 tokens (262K).
What can Union Alpha do?
Union Alpha supports image/vision input, tool use, and function calling.
Who created Union Alpha?
Union Alpha is developed by Stealth and was released on September 16, 2026.