DeepSeek Harness is an open-source agent app from DeepSeek for everyday tasks and coding, which you extend with add-ons called plugins.
In plain words
DeepSeek describes Harness as an open-source agent harness in which everything is a plugin. You can install plugins, or ask for new ones in chat using Creator mode, to add tools, skills and parts of the interface. It comes as a desktop app for Apple silicon Macs and 64-bit Windows, and developers can also start a web interface from the command line. It is in public preview, and DeepSeek warns that updates may break compatibility.
A quick example
Imagine asking it to turn a folder of sales spreadsheets into a short slide deck. The agent reads the files and builds the slides, and a plugin could add a chart style your team already uses.
Where you'll meet it
- Everyday tasks and coding on your own computer.
- Building your own agent setup from plugins.
Related
Sources
- DocsDeepSeek Harness, DeepSeek · read 3 Oct 2026
- Docsdeepseek-harness README, DeepSeek (GitHub) · read 3 Oct 2026
Checked by WhatIsAI against the sources above · 3 Oct 2026. Spotted an error? Report it.