Stealth Model "Space Bunny Alpha" on OpenRouter Suspected to Be MiniMax M3.1

On September 23, an anonymous third party launched a stealth test model, "Space Bunny Alpha," on OpenRouter and OpenCode, free to use and positioning itself as an extremely fast flash-level reasoning model. Because it identified itself as a MiniMax model when asked in Chinese, the community widely speculated it is the upcoming MiniMax M3.1. The model was later temporarily taken offline, with OpenRouter citing provider-side issues and promising to restore it with an announcement once stable.

Confirmed

• The model was provided by an anonymous third party, launched on OpenRouter on September 23 as a fast flash reasoning model with free access
• It supports adjustable reasoning effort, a 1M token context window, and text, image, and video multimodal input, with official messaging emphasizing speed and strong coding capability
• Reddit users found its chain-of-thought exhibits a typical "caveman mode" style—reasoning in ultra-terse expressions that save CoT tokens
• A user tested it by building an immersive 3D e-commerce site, validating its coding ability
• The model was temporarily taken offline; OpenRouter said the issue was on the provider's side and it would be restored and announced once stable

Unconfirmed

• Whether the model is actually MiniMax M3.1 remains speculation, based mainly on its Chinese-language self-identification and community fingerprinting; leaker @koltregaskes noted it has not been fully tested

Why it matters

• Stealth launches are a common way for vendors to stress-test new models before release; if Space Bunny Alpha is indeed MiniMax M3.1, it suggests MiniMax's next-generation model will focus on ultra-long context, multimodality, and cost-efficient reasoning
• The "caveman mode" chain-of-thought demonstrates a technical route of reducing reasoning token costs by compressing CoT expressions—worth watching to see if it ships in the official release

2026-09-24 ~ 2026-09-25 · 8 related posts

Full story(4 episodes)→

• Episode 1: Mystery Stealth Model "Space Bunny" Goes Free Across Platforms, Sparking Community Tests(2026-09-24, 6 posts)
• Episode 2: Stealth Model "Space Bunny Alpha" on OpenRouter Suspected to Be MiniMax M3.1(2026-09-24, 8 posts)
• Episode 3: Mystery Stealth Model Space Bunny Alpha Hits OpenRouter Free for the Weekend(2026-09-26, 7 posts)
• Episode 4: Mystery Model SpaceBunny Tops OpenCode Charts for 5 Days, Identity Unknown(2026-09-27, 5 posts)

• [source] Stealth model 'Space-Bunny-Alpha' on OpenRouter might be MiniMax M3.1 — koltregaskes · 2026-09-24
• [source] Stealth model Space-Bunny-Alpha pulled from OpenRouter, rumored to be MiniMax M3.1 — koltregaskes · 2026-09-24
• OpenRouter's stealth model Space Bunny Alpha: 1M context, multimodal, rumored to be MiniMax — airesearch12 · 2026-09-24
• MiniMax M3.1 (Space Bunny Alpha) Spotted Thinking in Token-Saving Caveman Mode — crusaderky · 2026-09-24
• Space Bunny Alpha Lands on OpenRouter: 1M-Context Multimodal Model With Adjustable Reasoning — HeyZoyaKhan · 2026-09-25

3 near-duplicate retellings: FrankFelixAI · mark_k · CurieuxExplorer