BotPsy: On-Device Personal Assistant with a Sub-Billion-Parameter Agentic Language Model

Tether AI Research has introduced BotPsy, a sub-billion-parameter agentic language model built on top of Qwen3.5-0.8B designed for on-device deployment and function calling. Tether AI Research states that the model achieves state-of-the-art agentic performance for its size, outperforming several larger models across multiple benchmarks while maintaining a focus on user privacy and secure workflows. The model is released with open weights under the Apache 2.0 license. Open article →