Union Alpha is a multimodal large model positioned for research, coding, and agentic workflows, claiming frontier-level performance across general-purpose tasks. It accepts text and images as input and returns text, supports tool calling via tools and tool_choice, and can output JSON through response_format (without JSON-schema enforcement). The model offers an enormous 262,144-token context window with up to 131,072 completion tokens, is free to use, and was released on September 16, 2026. It targets sustained engineering and agentic use cases with explicit support for structured outputs and long-horizon interactions.
Union Alpha is a stealth model hosted by a single anonymous third-party provider; OpenRouter forwards requests to that provider and is not the developer or owner. Prompts and completions are retained by the provider but are not used for training, and use is governed by the Stealth Model Terms. Measured performance shows a throughput of about 13 tokens/second and a median latency of 16.21 seconds; recent availability over the last 72 hours is reported near 89% while three-day uptime/availability metrics appear close to 100%. Integration is drop-in for OpenRouter-compatible APIs, with per-provider uptime and routing options available for load balancing.
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