Technology Radar
DeepSeek Harness (DSH) is an open-source runtime from DeepSeek AI for building customized coding and general-purpose agents. Rather than offering a monolithic assistant, DSH uses an "everything is a plugin" architecture powered by the Cordis kernel. The model adapter, tool registry, session log and agent loop are all plugins, organized into profiles: named plugin lists that you extend and override in your own YAML.
Cordis is a meta-framework built around spatiotemporal composability: plugins contribute registrations as reversible effects, so reloading and teardown unwind them predictably rather than leaving dangling state. The combination of this plugin architecture and spatiotemporal composability could provide a foundation for domain-specific enterprise harnesses and future self-improving harnesses.
DSH also treats observability as a first-class concern. Every model-visible interaction, including prompts, context injections, tool calls and subagent collaborations, is captured in an append-only session log. This allows runs to be inspected, resumed, forked, searched and replayed, providing a record of what a recomposed system actually did.
