Stealth line · live tracker
What is Space Bunny Alpha? The Anonymous Model on OpenRouter
Space Bunny Alpha appeared on OpenRouter on 23 September 2026 with no announcement, no maker and no price — the fourth anonymous model in the Alpha line, after Hunter Alpha (later Xiaomi MiMo-V2.5), OX Alpha (later Z.ai GLM 5.3 Flash) and Union Alpha (later Unbiased Pareto). Unlike those three it has not been claimed yet, so there is no before-and-after to print: this page holds one state, dated, and a status route that answers whether the id still resolves.
The short version
Verified specs
Read straight from the public catalogue and its endpoint payload — both re-checkable in one request. Rows that other people published rather than we confirmed are marked as such, and there are none on this page today.
| Field | Value |
|---|---|
| Model id | stealth/space-bunny-alpha resolves today |
| Listed | 2026-09-23 (14:48 UTC) the catalogue's own `created` field |
| Context window | 1,000,000 tokens 1M |
| Max output | 524,288 tokens the endpoint's cap |
| Input modalities | text, image, video output: text only |
| Price while anonymous | $0 in / $0 out per million tokens |
| Provider | Stealth OpenRouter's placeholder for an unnamed vendor |
| Provider disclosure | None no maker named, no announcement |
openrouter.ai/api/v1/models Verified 2026-09-28 Live status /api/space-bunny-alpha/status What the listing declares
Four things stand out, and all four are checkable. None of them is a performance claim.
The terms, in one sentence
Prompts and completions for this model may be retained by the provider but are not used for training; all other use is governed by the Stealth Model Terms.
The provider is anonymous *and* may keep what you send. That is not the same as training on it, and it is not nothing: if the state you send contains personal data, this is the sentence that decides whether you may. The listing and its terms →
What nobody knows yet
| Field | Value |
|---|---|
| Who makes it | Not public. OpenRouter's endpoint payload names the provider only as “Stealth”. |
| What it becomes | Unknown. The last two codenames were revealed within days; the one before ran for 41 days. |
| How long the free window lasts | Unknown. Every codename in this line has been free while anonymous, and none stayed free after the reveal. |
| How it performs | We have run nothing against it and publish no latency, cost or accuracy figure of our own. The listing's own adjectives are not a benchmark. |
Identity, as theories
Two versions of the same guess are circulating. Neither is evidence, and neither of us can test it; they are here because the alternative — a page that has no theory at all — is less honest than a page that says which parts are guesses. The checklist on the stealth index is explicit that identity theories belong on a separate surface, which is this section.
None beyond the listing. We could not attribute it to a maker from any public source. Why the theory exists at all: The listing's own words emphasise fast inference, coding and multimodal input, and every prior codename in this line was a preview of a product that shipped within weeks.
No overlap we can point at: different context window, different modalities, different (still zero) price. Why the theory exists at all: Union Alpha was revealed as Unbiased Pareto and delisted three days before this appeared; a lab running two previews a week apart is normal here.
Timeline
- 2026-09-23T14:48:04ZListed on OpenRouter as `stealth/space-bunny-alpha`.Listed on OpenRouter as `stealth/space-bunny-alpha`. The catalogue's own `created` field; public posts date it to the 23rd or 24th by timezone.
- 2026-09-24 → 2026-09-27Third-party write-ups appear (a Chinese-language news item, two aggregator pages, an announcement post from OpenRouter itself).Third-party write-ups appear (a Chinese-language news item, two aggregator pages, an announcement post from OpenRouter itself). No maker is named, and no repository or build we can find uses it yet.
- 2026-09-27We first read the listing: 1M context, 524,288 max output, text+image+video input, $0 in and out, `reasoning_effort` among the supported parameters.We first read the listing: 1M context, 524,288 max output, text+image+video input, $0 in and out, `reasoning_effort` among the supported parameters.
- 2026-09-28Still listed, still free, 99.Still listed, still free, 99.97% endpoint uptime over the previous 30 minutes. No disclosure, no rename, no price.
How to check all of this yourself
Read /api/space-bunny-alpha/status — it re-reads the catalogue on every request and answers
whether the id resolves, whether it is still free, and what the endpoint declares. Or fetch
openrouter.ai/api/v1/models and find stealth/space-bunny-alpha yourself; the
fields on this page are the fields in that payload.
Supported parameters, as declared today: reasoning, reasoning_effort, include_reasoning, max_tokens, temperature, top_p, tools, tool_choice, response_format.
FAQ
What is Space Bunny Alpha?
An anonymous model on OpenRouter, listed as stealth/space-bunny-alpha since 23 September 2026. The catalogue describes it as a large model with fast inference, strong coding and native multimodal input, a 1M-token context window and adjustable reasoning effort. Nobody has claimed it yet.
Is Space Bunny Alpha free?
Yes, as of 2026-09-28: the catalogue lists $0 for input and $0 for output, which is the normal state of a stealth preview. Every codename in this line has been free while anonymous, and none of them stayed free once the maker was named — treat the current price as a countdown rather than as a rate.
Can I send private data to it?
Read the terms first. The listing says prompts and completions may be retained by the provider and are not used for training. Retained is not the same as trained on, and it is the sentence that decides whether the state you send may leave your systems.
Who makes it?
Unknown, and we do not guess. The provider name in the endpoint payload is “Stealth”, OpenRouter's placeholder for an unnamed vendor. The identity theories on this page are labelled as theories and none of them is evidence.
How long will it stay up?
Unknown. In this line the anonymous window has run from 2 days (Union Alpha, 16–18 September 2026) to months (Hunter Alpha, March 2026). The page keeps a dated timeline and a live status route instead of a prediction: /api/space-bunny-alpha/status answers whether the id still resolves right now.
Where this fits
The stealth index lists every codename we can tie to a listing, with what each one turned out to be. The Alpha Line Report is the register of the 3 that have been revealed — Space Bunny Alpha is deliberately absent from it until it has an after, because a before-and-after table with half a row is a different table. What stealth models are explains the pattern itself.
Get notified when this one is named — or the next one appears
The reveal is the interesting day: the price stops being zero, the codename usually vanishes, and the maker's own model appears in the catalogue. One email per event.
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