Overview
VibeThinker-3B is a 3.1B-parameter reasoning model from WeiboAI, the AI team behind Weibo. It is a dense model post-trained on top of Qwen2.5-Coder-3B, and it carries a 131,072-token context window. The training pipeline, called the Spectrum-to-Signal Principle, pushes a compact model toward the kind of step-by-step math and code reasoning usually reserved for far larger systems.
The point of a model this small is where it runs. VibeThinker-3B is open-weight under an MIT license, so Atomic Chat loads it on your own machine and keeps every prompt and response on-device. Nothing leaves your computer, it works with no internet connection, and there is no API bill or rate limit.
What it is good at
VibeThinker-3B was tuned for verifiable reasoning: problems where an answer can be checked. Its capabilities cover thinking, reasoning, code, and tool calling.
- Competition math — the model thinks through multi-step problems and shows its work, the area where it posted strong AIME and HMMT scores in WeiboAI's reported benchmarks.
- Code generation and debugging — built on a Qwen2.5-Coder base, it writes functions, traces logic errors, and explains what a snippet does.
- Tool calling in agents — it supports structured tool calls, so it can drive local agent loops that hit a calculator, a search function, or your own scripts.
Running it locally
At 3.1B parameters the model is light. A 4-bit GGUF quantization runs in roughly 2 GB of memory, full bf16 weights need about 6 GB, and a 16 GB laptop or an Apple Silicon Mac handles it comfortably. The 131,072-token context is available, though a long context grows the KV cache and wants more headroom.
huggingface-cli download WeiboAI/VibeThinker-3B
You can serve the raw weights through Transformers or vLLM, or skip the setup entirely and load VibeThinker-3B in Atomic Chat with one click, which pulls a quantized build and runs it offline.
License
VibeThinker-3B is released under the MIT license. That permits commercial use, modification, fine-tuning, and redistribution, with the only requirement being that you keep the original copyright and license notice.