Tianyi Cui
8913d033dc
The input-message definition classifies ordinary user, steering, and injected context messages. Put that supported path first so readers can follow its matching rules directly, then handle deferred developer history afterward. Keep the append/checkpoint predicates, matched identity, null result for other events, and explicit developer error unchanged. This is a local readability change with no presentation or persistence behavior change. Validation: all 61 conversation-node definition tests pass, including user classification and developer refusal. Scoped lint and whitespace checks pass.
DeepSeek Harness
English | 中文
DeepSeek Harness (dsh) is an open-source agent harness developed by DeepSeek AI.
It is built on an everything-is-a-plugin architecture and powered by Cordis, whose design is described in A Programming Paradigm for Spatiotemporal Composability.
Documentation: https://deepseek-harness.github.io/deepseek-harness/
Developer preview
DeepSeek Harness is in developer preview and iterating rapidly. THERE WILL BE COMPATIBILITY-BREAKING CHANGES.
Review the safety notice before running the project.
Run
Run from npm
Install Node.js, then run:
npx @deepseek-ai/dsh web
The command starts the Web UI at http://127.0.0.1:3080 by default and opens it in the default browser for a local launch. An SSH launch only prints the host URL because the SSH client or editor owns the local forwarded address. Pass --no-open to run the server without opening a browser. See Web UI guide.
Run from source
To run from a repository checkout:
git clone https://github.com/deepseek-ai/deepseek-harness.git
cd deepseek-harness
pnpm install
pnpm run build
pnpm dsh web
pnpm run build prepares the repository artifacts. pnpm dsh web uses those built artifacts without rebuilding.
Community and support
- Submit feedback or bug reports through GitHub Discussions.
- Add the
dsh-plugintopic to your plugin repository for discoverability. - Join DeepSeek Harness Discord community.
Contributing
See CONTRIBUTING.md.
Development
Start with the development guide and architecture documentation.
For agents, follow AGENTS.md.
Citation
@misc{deepseek-harness2026,
title={DeepSeek Harness: Everything is a Plugin},
author={DeepSeek-AI},
year={2026},
publisher={GitHub},
howpublished={\url{https://github.com/deepseek-ai/deepseek-harness}},
}
License
Third-party dependencies and their licenses are disclosed in THIRD_PARTY_NOTICES.md.