Union Alpha

Union Alpha · released 2026-09-16 · 1 offer

Stealth preview model: OpenRouter lists stealth/union-alpha ("Union Alpha is a stealth model", added 2026-09-16, 262,144-token context, text and image input) free of charge during the preview. The developer is not disclosed, the weights are closed and the eventual price is not announced, so no cost per task is shown. Source: OpenRouter's model endpoint listing, retrieved 2026-09-16.

Providers

free (stealth preview) on OpenRouter — rate-limited and temporary, not a paid price; the eventual price is not announced.

Composite

0 of 7 inputs6 radar axes: DesignArena's two boards share one

No Composite score for this exact configuration: none of its inputs has a directly measured result. Family-attached evidence does not qualify this row for model-specific scoring.

Benchmark sheet

3 of 319 registered benchmark versions · bars show the percentile among all models measured on each benchmark.

2 of 3 values are announced, chart-read figures (‡): shown only, and never entering a score, a ranking or a percentile.

Compare this model →

Agentic

Terminal-Bench v4.0 (AA)announced value52.0%^{‡ preliminary, not independently measured}2026-09-18
Terminal-Bench v4.0 (AA) v4.0 → · Published board — Tests terminal-based work on the 66-task release using mini-SWE-agent v2.4.6.

Coding

DeepSWE (Datacurve, via Epoch AI)announced value73.0%^{‡ preliminary, not independently measured}2026-09-18
DeepSWE (Datacurve, via Epoch AI) published 2026-09-15 → · OpenRouter run, harness not stated — Pass rate of coding agents on original, long-horizon software engineering tasks, run by Datacurve with the mini-swe-agent harness.

Reasoning

LiveBench 2026-06-254376.12026-09-25
LiveBench 2026-06-25 → · Published board — A periodically refreshed suite of objectively graded tasks with separate category scores and an overall category mean.

Missing coverage · 316 benchmark versions

No result does not mean a zero, or that the model was never tested. Collection failures and disputed versions retain their distinct status.

Token offers by platform · 1 offer (Adjusted $/task)

Click any underlined price to see how it is estimated and where each input comes from. How we calculate adjusted cost.

1 offer within the active global filters; “price n/a” means the provider serves the model but publishes no direct token price we could collect — no other channel's price is shown in its place.

OpenRouter (1)

Prices via OpenRouter — what OpenRouter charges for each provider's endpoint, not the provider's own direct price. Source: openrouter.ai/stealth/union-alpha/providers, collected 2026-11-03.

Stealthfree (stealth preview)

not a paid price