Reference · FAQ
Frequently Asked Questions
Hunter Alpha, the Alpha line, and how we separate facts from claims. Everything here is either re-checkable against the public catalogue or labelled as a claim with a source.
General What is Hunter Alpha?
Hunter Alpha was the anonymous codename for the model now sold as Xiaomi MiMo-V2.5. It appeared on OpenRouter in March 2026 with a 1M-token context window and no maker attached, and Xiaomi confirmed the identity that same month. The codename is retired; the model page carries the current facts.
General Who created Hunter Alpha?
Xiaomi. The release was anonymous at launch — OpenRouter listed no vendor — and Xiaomi confirmed it as their MiMo model line in March 2026. That reveal is the pattern every Alpha-line release has followed since.
The Alpha line What are the Alpha models?
Alpha is the naming pattern for anonymous models published to OpenRouter as free previews, then claimed and renamed by their maker. Three have now run their course: Hunter Alpha (became Xiaomi MiMo-V2.5), OX Alpha (became Z.ai GLM 5.3 Flash) and Union Alpha (became Unbiased Pareto on 2026-09-18, two days after it appeared). None of the three is anonymous or free any more.
The Alpha line Which stealth model is live right now?
None — there is no anonymous release on OpenRouter as of 2026-09-18. The last one, Union Alpha, was delisted the same day it was revealed as Unbiased Pareto. The line has produced a new codename roughly every one to two months since March 2026, so the honest answer is "check the register" rather than "this one". Our tracker re-reads the catalogue live instead of trusting a snapshot.
Access & pricing Is Hunter Alpha still free?
No. Hunter Alpha was free while it was anonymous. Once Xiaomi claimed it and it became MiMo-V2.5, it turned into a normal paid model on OpenRouter with published per-million pricing. Free previews on this line have ended every time so far.
Access & pricing Is Union Alpha free, and for how long?
It is not free any more. Union Alpha was billed at $0 per million tokens for the two days of its stealth window (16–18 September 2026); the same day it was revealed as Unbiased Pareto, the stealth route was delisted and the model was relisted at $2.50 input / $7.50 output per million. The ≈$0.50 / $1.50 figure that circulated during the window was a third-party claim about an unreleased model, and the real listing did not match it.
Access & pricing Does Hunter Alpha support images?
The current catalogue entry for Xiaomi MiMo-V2.5 lists text, vision, audio and video input. The anonymous preview was described as text-only at the time, so treat modality as something to re-check on the model page rather than something fixed for the life of the codename.
General What happens when a stealth model is revealed?
Three things, in order: the maker claims it, the codename is retired and the model is renamed to a product name, and the free preview becomes ordinary paid pricing. The old codename usually disappears from the catalogue, which is why our register keeps the history instead of relying on a listing that will not last.
Method How do you decide what counts as a fact here?
Fields you can re-read — context window, output cap, modalities, tool support, price — are reported as facts with a source and a date. Everything else, including parameter counts, architecture claims and identity theories, is labelled as a claim with whoever said it. We would rather publish a shorter page than a confident-sounding guess.
Method Where do the community discussions happen?
Hacker News, Reddit's r/LocalLLaMA and the OpenRouter Discord are where testers compare notes on a new release. The tracker paraphrases what they report and marks it as a claim, never as a specification, and links the original where we can.
Union Alpha tracker Stealth models register Compare every model