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Model usage data, product updates, and research reports. One email each week.

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This stealth model was developed and operated by Unbiased, revealed to be Unbiased ParetoOpens in new tab. Prompts and completions for this model may have been retained by the provider but are not used for training; all other use is governed by the Stealth Model TermsOpens in new tab.

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Union Alpha

stealth/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 was a stealth model, revealed to be ParetoOpens in new tab by Unbiased. OpenRouter routed requests to it and was not its developer, owner, or provider. Prompts and completions may be retained by the provider but are not used for training; all other use is governed by the Stealth Model TermsOpens in new tab. The free stealth period has ended; use Pareto at https://openrouter.ai/unbiased/paretoOpens in new tab.

Modalities

Context

262K

Released

Sep 16, 2026

ActivityFAQExplore

Activity

Token volume and request traffic to this model over time.

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Ox Alpha

Ox Alpha is a reasoning model designed for coding, sustained agentic work, and production workloads. It is suited for long-horizon software engineering, complex reasoning, and workflows that combine text with visual context.

Ox Alpha is a stealth model. It is developed and operated by a third-party provider who has chosen to remain anonymous during this preview. OpenRouter routes requests to it and is not its developer, owner, or provider. Prompts and completions are retained by the provider and are not used for training; all other use is governed by the Stealth Model Terms.

Text1.0M context

Frequently asked questions

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 was a stealth model, revealed to be Pareto by Unbiased. OpenRouter routed requests to it and was not its developer, owner, or provider.

Union Alpha has a 262,144 token context window.

Union Alpha accepts text and images as input and returns text.

Union Alpha was released on September 16, 2026.