DeepSeek launches open-source agent framework DeepSeek Harness

DeepSeek has released the early developer preview of DeepSeek Harness, an open-source agent framework built on the Cordis meta-framework. The system utilizes a modular “everything is a plugin” architecture, allowing developers to combine or replace models, tools, skills, sandboxes, and file systems without needing to modify the core source code. This design aims to prevent system crashes or forced restarts when components are added or removed.

The framework includes Chain of Thought (CoT) tracking, which uses append-only logs to record reasoning processes, tool calls, and context injections. This allows users to inspect, branch, or replay specific event streams via a Trajectory view.

As the ecosystem grows, community resources like DSH Hub have emerged to provide directories for plugins and clients. DSH Hub emphasizes security and transparency by requiring all listed items to link to public GitHub repositories, allowing developers to inspect source code, licenses, and release histories before integration.