DeepSeek AI's open-source agent harness (CLI dsh, MIT, 233k+ stars). The kernel provides only plugin-system semantics; tools, surfaces and model access all attach as plugins, on top of Cordis' paradigm for spatiotemporal composability (arXiv:2608.25512). It is in developer preview with an explicit warning about compatibility-breaking changes, and SAFETY.md is required reading before you run it. We have not benchmarked it, so we grade this entry as needing reproduction.