A powerful AI model that appeared anonymously on a developer platform last week was revealed on Wednesday to be from Chinese smartphone and EV giant Xiaomi, after it fuelled speculation that start-up DeepSeek was quietly testing its next-generation system ahead of a launch.
The release of DeepSeek’s low-cost models DeepSeek-V3 and R1 triggered a global tech stock selloff last year, causing investors to question whether US AI firms needed to spend billions of dollars on AI computing power. Since then, there has been a great deal of interest in DeepSeek-V4, a next-generation model that has yet to be released.
The mysterious free model, called Hunter Alpha, surfaced on the AI gateway platform OpenRouter on 11 March without any developer attribution and was later described by the platform as a “stealth model”.
Xiaomi’s AI model team MiMo, run by former DeepSeek researcher Luo Fuli, on Wednesday said that Hunter Alpha was an “early internal test build of MiMo-V2-Pro”, a flagship model designed to serve as the “brain” of AI agents, tools that can allow users to execute complex tasks with fewer human prompts and supervision when compared with a chatbot.
Xiaomi’s new model release comes at a time when OpenClaw, an open-source agent framework, is being rapidly adopted by users of all stripes in China.
“I call this a quiet ambush — not because we planned it, but because the shift from chat to agent paradigm happened so fast, even we barely believed it,” Luo said in an X post on Thursday. “People ask why we move so fast. I saw it first-hand building DeepSeek R1.”
Shares surge
MiMo-V2-Pro will partner with five major agent frameworks, including OpenClaw, to offer a week of free access to developers worldwide.
Xiaomi’s Hong Kong-listed shares surged as much as 5.8% on Thursday.
Hunter Alpha’s profile page describes it as a trillion-parameter model, meaning it was trained using roughly one trillion adjustable values that determine how the system processes language and generates responses.
Read: A mystery AI model has developers buzzing
The system also advertises a context window of up to one million tokens, a measure of how much text an AI model can process or remember during a single interaction. A token roughly corresponds to a short piece of text, such as part of a word.
“The combination that stood out was Hunter Alpha’s million-token context paired with reasoning capability and free access,” said Nabil Haouam, an engineer who builds AI agent systems. “Most frontier models with that context window come with real cost at scale.”
Those specifications resembled expectations in local media for DeepSeek’s next-generation V4 model, which Chinese outlets have reported could launch as early as April.
Stealth model launches are not unusual, as platforms like OpenRouter allow developers to send queries to dozens of AI models through a single interface, making them a popular testing ground for new systems.
An anonymous model called Pony Alpha appeared on OpenRouter in February before Chinese firm Zhipu AI confirmed it was part of its GLM-5 system five days later.
Read: Bumper orders for Xiaomi’s YU7 SUV heighten threat to Tesla
A notice on Hunter Alpha’s profile page said all prompts and completions for the model “are logged by the provider and may be used to improve the model”, underscoring the industry-wide practice of using stealth model launches for unbiased feedback. — Eduardo Baptista, (c) 2026 Reuters
Get breaking news from TechCentral on WhatsApp. Sign up here.