The short definition

DeepSeek Harness is built on Cordis, where plugins register services, typed events, and reversible effects through a shared context. The official architecture treats the model adapter, tool registry, session log, agent loop, sandbox, and user interfaces as plugins rather than privileged core features.

Plugin, bundle, and profile are different

These terms describe different layers of the same composition system. Keeping them separate makes installation and troubleshooting much easier.

TermWhat it isWhat it answers
Plugin moduleCode mounted by Cordis through an apply function, object, or Service class.What behavior is contributed?
BundleAn installable npm package with a dsh.bundle manifest and a Cordis patch.What configuration layer does this package add?
ProfileA named runnable composition such as web or headless.Which bundles and user overrides boot together?

How DSH composes a running system

A profile starts with an empty plugin tree. DSH applies bundle patches in profile order, then the profile patch, the machine-level patch, and finally any command-line patch overlays. Later layers can replace an earlier row, and unloading a plugin reverses the effects it registered.

Inspect the composed plugin tree
dsh --profile web --dump-config

What a plugin can add

The architecture exposes documented extension seams instead of requiring a fork of the harness.

  • Model-facing tools and tool execution policy.
  • Model providers and streaming adapters.
  • Web, terminal, editor, and conversation-node interfaces.
  • Filesystem, shell, sandbox, terminal, memory, and storage providers.
  • Agent events, background jobs, commands, goals, and durable session state.

How community plugins are published

The official DeepSeek Harness contribution guide asks authors to publish a public repository and associate it with the dsh-plugin GitHub Topic. That Topic is the official discovery signal; independent registries can then add classification, compatibility history, and review context.

  • Use a public repository with clear installation instructions.
  • Add the exact dsh-plugin Topic on GitHub.
  • Document supported profiles, platforms, permissions, and external services.
  • Treat every compatibility statement as version- and date-specific while DSH remains in developer preview.

DeepSeek Harness is in developer preview. Recheck official documentation and plugin evidence when the host version changes.

Official sources

These primary sources were used to verify the technical details in this guide.